Science Photo Essay

2009-11-01T22:49:00.000-08:00

For some 5 millennia the only metal, copper was known to man, and therefore has all the possible applications of metal. It was 1 Metal mined and manufactured by man and has a great importance to older days because of its great availability. It was also suitable for creating copper-metal weapons, tools, art objects and jewelry.

The wide use and applications of copper metal over the years after its discovery are well documented. Today you can see, this versatile metal objects, such asfamiliar, such as coins in his pocket, the Statue of Liberty and sanitary products in more than 80% of all households in the United States.

The metal is of inestimable value to humanity in a broad range of applications ranging from the production of alloys for power transmission, the micro-electronics. Each of the thousands of applications of the metal based on a combination of items to ensure material that is perfect for the purpose. Good thermal and electrical conductivity associated with forceDuctility and excellent corrosion resistance, some of the characteristics of this metal, the copper a precious metal for a variety of applications.

The metal is found generally as the multivalent cations, Cu (II), and less than the monovalent, Cu (I).

Production of copper

Over two hundred years, the United Kingdom was an important source of copper for the world, and there were mines in Wales and Cornwall. These mines are now closed and now the largest copper mines areSituation in Chile and North America, producing several thousand tonnes of copper per year. The most important ores of copper are:

Chalcopyrite

Bornite

Malachite.

These ores are extracted either with traditional mining techniques or by leaching. The pure metal is then retrieved with the physical and chemical processes.

Recycling

Copper is very well suited to recycling and can be melted again and again without loss ofProperties. For example, old copper plumbing pipe fittings, pipes and radiators important sources of recycled copper. All these products can be melted down and made into new products. In the future, a small amount of copper in the cell phone will get its worth.

Did you know that copper

Is found everywhere in the crust of the earth.

Is of crucial importance for the people. Adults need 2-3 mg daily in their diet.

Is crucial for the metabolism of allliving organisms.

Provides superior corrosion resistance, excellent electrical and thermal conductivity.

Good formability.

Is environmentally friendly and recyclable. More than 80% copper is mined each still in use.

Has been extensively used in tools and jewelry from over 6,000 years ago.

When alloyed with zinc, brass produced.

When alloyed with tin produces bronze.

Russia Plans for Nuclear Space ship going to Mars

2009-11-01T16:28:00.000-08:00

Russia should build a new nuclear-powered spaceship for prospective manned missions to Mars and other planets.

Anatoly Perminov first proposed building the ship at a government meeting but didn't explain its purpose. President Dmitry Medvedev backed the project and urged the government to find the money.

In remarks posted on his agency's Web site, Perminov said the nuclear spaceship should be used for human flights to Mars and other planets. He said the project is challenging technologically, but could capitalize on the Soviet and Russian experience in the field.

Perminov said the preliminary design could be ready by 2012, and then it would take nine more years and cost 17 billion rubles (about $600 million, or euro400 million) to build the ship.

"The project is aimed at implementing large-scale space exploration programs, including a manned mission to Mars, interplanetary travel, the creation and operation of planetary outposts," Perminov's Web statement said.

The ambitious plans contrast with Russia's slow progress on building a replacement to its mainstay spacecraft — the Soyuz.

Russia is using Soyuz booster rockets and capsules, developed 40 years ago, to send crews to the International Space Station. The development of a replacement rocket and a prospective spaceship with a conventional propellant has dragged on with no end in sight.

Despite its continuing reliance on the old technology, Russia stands to take a greater role in space exploration in the coming years. NASA's plan to retire its shuttle fleet next year will force the United States and other nations to rely on the Russian spacecraft to ferry their astronauts to and from the International Space Station until NASA's new manned ship becomes available.

Perminov said the new nuclear-powered ship should have a megawatt-class nuclear reactor, as opposed to small nuclear reactors that powered some Soviet military satellites. The Cold War-era Soviet spy satellites had reactors that produced just a few kilowatts of power and had a life span of about a year.

Igor Lisov, a Moscow-based expert on Russian space program, said the prospective ship would use a nuclear reactor to run an electric rocket engine.

Soviet work on a nuclear-powered electric rocket engine dates back to the 1960s when Soviet engineers began developing plans for a manned flight to Mars.

Russia's experience in building nuclear-powered satellites would also help develop the new spaceship. "It will require a significantly more powerful nuclear reactor, but the task is quite realistic," Lisov said.

Stanley Borowski, a senior engineer at NASA specializing in nuclear rocket engines, said they have many advantages for deep space missions, such as to take astronauts and gear to Mars. In deep space, nuclear rockets are twice as fuel-efficient as conventional rockets, he said.

NASA has used small amounts of plutonium in deep space probes, including those to Jupiter, Saturn, Pluto and heading out of the solar system.

The only planetary mission currently considered by Russia is a plan to send a probe to one of Mars' twin moons, Phobos. It was set to launch this year, but was delayed.

chloroplast

2009-11-01T02:02:00.000-08:00

Chloroplasts are the food producers of the cell. They are only found in plant cells and some protists. Animal cells do not have chloroplasts. Every green plant you see is working to convert the energy of the sun into sugars. Plants are the basis of all life on Earth. They create sugars, and the byproduct of that process is the oxygen that we breathe. That process happens in the chloroplast. Mitochondria work in the opposite direction and break down the sugars and nutrients that the cell receives.

Making Food

Super basic process of photosynthesis The purpose of the chloroplast is to make sugars and starches. They use a process called photosynthesis to get the job done. Photosynthesis is the process of a plant taking energy from the Sun and creating sugars. When the energy from the Sun hits a chloroplast, chlorophyll uses that energy to combine carbon dioxide (CO2) and water (H2O). The molecular reactions create sugar and oxygen (O2). Plants and animals then use the sugars (glucose) for food and energy. Animals also use the oxygen to breathe.

Different Chlorophyll Molecules

We said that chlorophyll molecules sit on the outside of the thylakoid sacs. Not all chlorophyll is the same. Three types of chlorophyll can complete photosynthesis. There are even molecules other than chlorophyll that are photosynthetic. One day you might hear about carotenoids, phycocyanin (bacteria), phycoerythrin (algae), and fucoxanthin (brown algae). While those compounds might complete photosynthesis, they are not all green or the same structure as chlorophyll.

photosynthesis

2009-11-01T01:47:00.000-07:00

Photosynthesis is the process by which plants, some bacteria, and some protistans use the energy from sunlight to produce sugar, which cellular respiration converts into ATP, the "fuel" used by all living things. The conversion of unusable sunlight energy into usable chemical energy, is associated with the actions of the green pigment chlorophyll. Most of the time, the photosynthetic process uses water and releases the oxygen that we absolutely must have to stay alive. Oh yes, we need the food as well!

We can write the overall reaction of this process as:

6H₂O + 6CO₂ ----------> C₆H₁₂O₆+ 6O₂

_{Photosynthesis takes place primarily in plant leaves, and little to none occurs in stems, etc. The parts of a typical leaf include the upper and lower epidermis, the mesophyll, the vascular bundle(s) (veins), and the stomates. The upper and lower epidermal cells do not have chloroplasts, thus photosynthesis does not occur there. They serve primarily as protection for the rest of the leaf. The stomates are holes which occur primarily in the lower epidermis and are for air exchange: they let CO2 in and O2 out. The vascular bundles or veins in a leaf are part of the plant's transportation system, moving water and nutrients around the plant as needed. The mesophyll cells have chloroplasts and this is where photosynthesis occurs.}

_{[Chloroplast] As you hopefully recall, the parts of a chloroplast include the outer and inner membranes, intermembrane space, stroma, and thylakoids stacked in grana. The chlorophyll is built into the membranes of the thylakoids.}

_{Chlorophyll looks green because it absorbs red and blue light, making these colors unavailable to be seen by our eyes. It is the green light which is NOT absorbed that finally reaches our eyes, making chlorophyll appear green. However, it is the energy from the red and blue light that are absorbed that is, thereby, able to be used to do photosynthesis. The green light we can see is not/cannot be absorbed by the plant, and thus cannot be used to do photosynthesis.}

_{The overall chemical reaction involved in photosynthesis is: 6CO2 + 6H2O (+ light energy) C6H12O6 + 6O2. This is the source of the O2 we breathe, and thus, a significant factor in the concerns about deforestation.}
_{There are two parts to photosynthesis:}

_{The light reaction happens in the thylakoid membrane and converts light energy to chemical energy. This chemical reaction must, therefore, take place in the light. Chlorophyll and several other pigments such as beta-carotene are organized in clusters in the thylakoid membrane and are involved in the light reaction. Each of these differently-colored pigments can absorb a slightly different color of light and pass its energy to the central chlorphyll molecule to do photosynthesis. The central part of the chemical structure of a chlorophyll molecule is a porphyrin ring, which consists of several fused rings of carbon and nitrogen with a magnesium ion in the center.}

_{The energy harvested via the light reaction is stored by forming a chemical called ATP (adenosine triphosphate), a compound used by cells for energy storage. This chemical is made of the nucleotide adenine bonded to a ribose sugar, and that is bonded to three phosphate groups. This molecule is very similar to the building blocks for our DNA.}

_{The dark reaction takes place in the stroma within the chloroplast, and converts CO2 to sugar. This reaction doesn't directly need light in order to occur, but it does need the products of the light reaction (ATP and another chemical called NADPH). The dark reaction involves a cycle called the Calvin cycle in which CO2 and energy from ATP are used to form sugar. Actually, notice that the first product of photosynthesis is a three-carbon compound called glyceraldehyde 3-phosphate. Almost immediately, two of these join to form a glucose molecule.}

_{Most plants put CO2 directly into the Calvin cycle. Thus the first stable organic compound formed is the glyceraldehyde 3-phosphate. Since that molecule contains three carbon atoms, these plants are called C3 plants. For all plants, hot summer weather increases the amount of water that evaporates from the plant. Plants lessen the amount of water that evaporates by keeping their stomates closed during hot, dry weather. Unfortunately, this means that once the CO2 in their leaves reaches a low level, they must stop doing photosynthesis. Even if there is a tiny bit of CO2 left, the enzymes used to grab it and put it into the Calvin cycle just don't have enough CO2 to use. Typically the grass in our yards just turns brown and goes dormant. Some plants like crabgrass, corn, and sugar cane have a special modification to conserve water. These plants capture CO2 in a different way: they do an extra step first, before doing the Calvin cycle. These plants have a special enzyme that can work better, even at very low CO2 levels, to grab CO2 and turn it first into oxaloacetate, which contains four carbons. Thus, these plants are called C4 plants. The CO2 is then released from the oxaloacetate and put into the Calvin cycle. This is why crabgrass can stay green and keep growing when all the rest of your grass is dried up and brown.}

_{There is yet another strategy to cope with very hot, dry, desert weather and conserve water. Some plants (for example, cacti and pineapple) that live in extremely hot, dry areas like deserts, can only safely open their stomates at night when the weather is cool. Thus, there is no chance for them to get the CO2 needed for the dark reaction during the daytime. At night when they can open their stomates and take in CO2, these plants incorporate the CO2 into various organic compounds to store it. In the daytime, when the light reaction is occurring and ATP is available (but the stomates must remain closed), they take the CO2 from these organic compounds and put it into the Calvin cycle. These plants are called CAM plants, which stands for crassulacean acid metabolism after the plant family, Crassulaceae (which includes the garden plant Sedum) where this process was first discovered.}

What is Plasma ?

2009-10-30T03:38:00.000-07:00

Plasma is by far the most common form of matter. Plasma in the stars and in the tenuous space between them makes up over 99% of the visible universe and perhaps most of that which is not visible.

On earth we live upon an island of "ordinary" matter. The different states of matter generally found on earth are solid, liquid, and gas. We have learned to work, play, and rest using these familiar states of matter. Sir William Crookes, an English physicist, identified a fourth state of matter, now called plasma, in 1879.

Plasma temperatures and densities range from relatively cool and tenuous (like aurora) to very hot and dense (like the central core of a star). Ordinary solids, liquids, and gases are both electrically neutral and too cool or dense to be in a plasma state.

The word "PLASMA" was first applied to ionized gas by Dr. Irving Langmuir, an American chemist and physicist, in 1929.

Plasma consists of a collection of free moving electrons and ions - atoms that have lost electrons. Energy is needed to strip electrons from atoms to make plasma. The energy can be of various origins: thermal, electrical, or light (ultraviolet light or intense visible light from a laser). With insufficient sustaining power, plasmas recombine into neutral gas.

Plasma can be accelerated and steered by electric and magnetic fields, which allows it to be controlled and applied. Plasma research is yielding a greater understanding of the universe. It also provides many practical uses: new manufacturing techniques, consumer products, the prospect of abundant energy, more efficient lighting, surface cleaning, waste removal, and many more application topics.

Microbial Fuel

2009-10-24T00:40:00.000-07:00

Fuel cells have a very high buzz factor these days. These seemingly magical devices create electricity from hydrogen and oxygen—producing pure water as their only byproduct. Several major cities already have fleets of buses that use fuel cells. Auto manufacturers promise us that within a few years, we’ll be able to buy fuel cell-powered cars that create no pollution at all—thus enabling us to reduce our dependence on oil and slow global warming while saving money with inexpensive hydrogen fuel. Spacecraft have used fuel cells for decades to produce electricity, since the hydrogen and oxygen they need are both conveniently available in onboard tanks. And in the near future, fuel cells may even be put to more prosaic uses, powering notebook computers, cell phones, and other personal electronic devices.

Ship of Fuels

But although fuel cell technology is by no means new, it has yet to achieve large-scale commercial success. One of the main reasons is that hydrogen, the most common fuel, is surprisingly difficult to obtain. Even though hydrogen is present in water, air, and organic matter of all sorts, pure hydrogen is harder to come by. If you use electrolysis to separate water into hydrogen and oxygen so that you can use the hydrogen as fuel to produce electricity, you get into a sort of vicious cycle of energy consumption—it takes almost as much energy to produce the hydrogen in the first place as the hydrogen will later provide when used as fuel. Once you have the pure hydrogen, it’s a pain to store and deliver it safely. So the net cost is fairly high, and the net efficiency is fairly low. If only there were a handier way to obtain hydrogen—or better yet, a fuel cell design that used a more conveniently obtained fuel. Both of these hopes may be met by microbial fuel cells (MFCs), which use bacteria to process virtually any organic matter and turn it into electricity.

When I say “virtually any organic matter,” I’m referring to, for example, raw sugar, rotten fruit, dead flies, or even human waste. And in the latter case, microbial fuel cells offer the intriguing capability of purifying the waste and producing fresh water while also creating electricity.

Fuel Cells 101

Fuel cells convert chemical energy into electrical energy, as do batteries, but fuel cells can sustain their output of electricity as long as the chemical input is maintained. Electricity, of course, is simply a movement of electrons. To oversimplify greatly, a basic fuel cell consists of two sections: the anode, or negative terminal, and the cathode, or positive terminal. These sections are separated by a special membrane that allows only protons (positively charged particles) to pass through, while inhibiting the flow of electrons (negatively charged particles). One substance (typically hydrogen) is fed into the anode section, where a chemical reaction splits off its electrons. Since the electrons can’t flow through the membrane, they flow into the anode, which is connected to an external circuit. The electrons return to the cell’s cathode, where they combine with another substance (typically oxygen) in another chemical reaction that creates a byproduct (in this case, water).

One type of microbial fuel cell still relies on hydrogen as the ultimate fuel, but instead of pumping it in from a tank, uses bacteria to create it. Certain strains of E. coli and T. neapolitana, for instance, feed on organic matter and produce hydrogen as a waste product, rather than the more common methane. When incorporated into a fuel cell design, a colony of these critters nicely solves the hydrogen supply problem. A chemical additive then facilitates the transfer of electrons from the hydrogen to the anode.

Potty of Gold

Other bacteria, some of which are found naturally in sewage, can enable a fuel cell to skip the hydrogen step altogether. These bacteria consume organic matter and directly transfer electrons to the fuel cell’s anode. This makes the fuel cell design much simpler, and also increases the feasibility of using the fuel cells to purify the waste fuel into clean water.

In current MFC designs, efficiency is low; it takes a very large apparatus, and a lot of waste input, to produce meaningful amounts of electricity. Researchers are hopeful, however, that they can improve the efficiency significantly, making microbial fuel cells a practical means of supplying electricity on a large scale. MFCs are especially attractive for use in long-distance space travel, as they can produce both fresh water and electricity from waste products that would otherwise be useless cargo. Meanwhile, microbial fuel cells are also being considered as long-term power sources for autonomous robots, marine sensing equipment, and other remote electronic devices. A team at the University of the West of England, Bristol built a small proof-of-concept robot called EcoBot II that runs—though quite slowly—on a diet of dead flies or rotten fruit. A future version of the machine may even be designed to find or capture its own food. But not to worry: man-eating robots, I am reliably informed, are still decades away

Fuel-cell flow

2009-10-24T00:37:00.000-07:00

Let’s take a look at that most common of electrical sources, the battery. Batteries usually consist of two metal “poles”, with an acid or salt solution sandwiched between them. The chemical reaction of these components makes electrons collect on the negative (-) terminal of the battery and, when an electrical item is attached to the battery, these electrons are used for power. At the same time, though, the chemical reaction within the battery is continuing, which eventually reduces the difference in charge between the positive (cathode) and negative (anode) poles… and the battery stops producing power.

How about a fuel cell? There are a number of different types of fuel cell, but we’ll look at hydrogen cells here. Fuel cells still work by transferring electrons, but the source of those electrons is different: the electrons are stripped from the hydrogen fuel itself. The fuel cell consists of two catalyst-coated electrodes, separated by a membrane which only allows charged particles to pass through. The two electrodes are also connected to an electrical load, such as a car’s motor. Hydrogen is fed into the cell at one end, where the catalyst prompts the Hydrogen to become positively charged H+. The dropped electron from the Hydrogen is picked up by the electrode (which becomes the negative anode), and used to power the load (i.e. the car). Meanwhile, the positively charged H+ passes through the membrane to the other electrode (the cathode), where it is combined with oxygen from the air, and the returning electrons, to become water.

Fuel cell Working

2009-10-24T00:34:00.000-07:00

A fuel cell generates electrical power by converting the chemical energy of a fuel into electrical energy by way of an electrochemical reaction without combustion. Fuel cells typically utilize hydrogen as the fuel and oxygen (from air) as the oxidant. The reaction results in electricity, by-product water and heat.

There are a number of fuel cell technologies, but we are focussing on proton exchange membrane (PEM) fuel cells. The basic cell consists of two electrodes, the anode and the cathode, separated by a polymer electrolyte membrane. Each of the electrodes is coated on one side with a platinum-based catalyst.

Hydrogen fuel is fed into the anode and air enters through the cathode. In the presence of the platinum catalyst, the hydrogen molecule splits into two protons and two electrons. The electrons from the hydrogen molecule flow through an external circuit creating an electrical current. Protons from the hydrogen are transported through the polymer electrolyte membrane and combine at the cathode with the electrons and oxygen from the air to form water and generate by-product heat.

Practical fuel cells comprise many cells connected in series to generate useful voltage and power levels.

Biomass ConversionHow does biomass get converted into ethanol?

2009-10-22T18:12:00.000-07:00

“Increasing supplies of renewable energy and using more energy efficient technologies must continue to play an indispensable role in reducing greenhouse gas emissions and meeting the rapidly growing demand for energy,” said Samuel Bodman, the U.S. secretary of energy.*

Victor Lin, a professor of chemistry and director of the Center for Catalysis, will lead the Iowa State project. The project also includes Robert C. Brown, the Iowa Farm Bureau Director of the Bioeconomy Institute; George Kraus, the director of the Institute for Physical Research and Technology; Marek Pruski, a scientist for the Department of Energy’s Ames Laboratory located at Iowa State; and Justinus Satrio, a project manager at the Center for Sustainable Environmental Technologies.

They’re working to develop a biomass-to-ethanol system that would work like this: Plant biomass such as corn stalks and switchgrass would be broken down by fast pyrolysis, a process that uses heat at 900 degrees Fahrenheit in the absence of oxygen to convert biomass into a bio-oil. The bio-oil would be gasified with steam and/or oxygen at 1,100 to 1,500 degrees Fahrenheit to produce a synthesis gas, a mixture of carbon monoxide, hydrogen, carbon dioxide and short-chain hydrocarbon gases. The hydrogen and carbon monoxide in the synthesis gas would be reacted with a nanotechnology-based catalyst to produce ethanol fuel.

Lin said researchers have looked at catalysts to produce ethanol from synthesis gas for years. But there were some problems with the old chemistry and research progress has slowed since the early 1990s. The chemistry didn’t produce the selective reactions necessary for efficient production. There were also issues with controlling those reactions.

But now, “With the emphasis on biomass and biorenewables, I think there will be a renaissance of this research and technology,” Lin said.

His idea for a new kind of catalyst is based on solid nanospheres just 250 billionths of a meter in diameter that have honeycomb channels running through them. Lin said those channels can be loaded with a metallic catalyst and other species that can promote higher reactivity and product selectivity. The new technology, because of the nanoporous structure and the unique spatial arrangement of the catalytic components, solves some of the selectivity and control problems of the old chemistry.

Lin has already worked on the synthesis gas-to-ethanol catalyst for a year and has filed a patent application.

Satrio, of Iowa State’s Center for Sustainable Environmental Technologies, called the research collaboration “a very exciting project. This is on the cutting edge of this technology.”

The center’s focus will be to develop a system that efficiently and economically produces clean synthesis gas that’s ready to be reacted with Lin’s catalyst. Center researchers will use the two thermochemical technologies (fast pyrolysis and gasification) with the goal of developing a complete conversion system that makes economic sense for the future.

Transporting biomass to fuel production plants isn’t easy or cheap because of the bulk and quantities involved. The Department of Energy has estimated a biorefinery would need at least 2,000 tons of biomass per day. A year's supply would cover 100 acres with 25 feet of biomass.

The Iowa State idea calls for biomass to be transported to small, local fast pyrolysis plants that would convert the plant fiber into liquid bio-oil, Satrio said. The bio-oil would be much easier to transport to bigger, regional facilities where it could be efficiently gasified at high pressure and catalytically converted into ethanol.

The departments of agriculture and energy said the 21 research projects won grants because they can advance President George Bush’s Advanced Energy Initiative. The initiative’s goals are to change the way the country powers its cars, homes and businesses by increasing energy efficiency and diversifying energy sources. Funding for the projects will be provided through the departments’ Biomass Research and Development Initiative.

*The U.S. Department of Agriculture and the U.S. Department of Energy recently announced they’ll support the research with a two-year grant of up to $944,899. The departments are awarding $18.4 million over three years to 21 universities and companies for biomass research, development and demonstration projects.

Sedna’s flyby

2009-10-21T23:37:00.000-07:00

Computer simulations show a close encounter with a passing star about 4 billion years ago may have given our solar system its abrupt edge and put small, alien worlds into distant orbits around our sun.

The study, which used a supercomputer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., was published in the Dec. 2 issue of the journal Nature by physicist Ben Bromley of the University of Utah and astronomer Scott Kenyon of the Smithsonian Astrophysical Observatory in Cambridge, Mass.

Image by tonynetone via Flickr

Bromley and Kenyon simulated what would have happened if our sun and another star in our Milky Way galaxy had passed a relatively close 14 billion to 19 billion miles from each other a few hundred million years after our solar system formed. At that t

Image via Wikipedia

ime, our solar system was a swirling “planetary disk” of gas, dust and rocks, with planets newly formed from the smaller materials.

Imagine the encounter of two young solar systems by envisioning two circular saw blades brushing past each other while spinning rapidly. When they make contact, their outer edges are buzzed off by the other saw. But in the case of planetary disks, colliding rocks at the edges of the solar systems are pulverized into pebbles, causing particles to be flung in all directions.

“Any objects way out in the planetary disk would be stirred up greatly,” says Bromley, an associate professor of physics at the University of Utah.

Bromley and Kenyon conclude the shearing motion and dueling gravity of the passing stars could have done several things:

-- Taken young planets formed with circular orbits in our solar system and catapulted them into highly elongated orbits. That may explain the existence of Sedna, a “planetoid” that orbits beyond Pluto and measures between 600 and 1,000 miles wide.

-- Created a sharp edge to the solar system by shearing off the outer part of the Kuiper belt, a collection of small, rocky-and-icy objects in space starting beyond Neptune’s orbit and ending abruptly about 4.7 billion miles from the sun.

Image by Arenamontanus via Flickr

-- Allowed our sun and solar system to capture a planet or smaller object from the passing star’s solar system. Sedna might be an example.

Astronomers have been searching for years for extrasolar planets, or planets in other solar systems. Few considered the possibility that “the nearest extrasolar planet might be right here in our solar system,” says Kenyon.

Computer simulations of a close encounter by two stars – a stellar flyby – demonstrated there is a chance a planet could be captured from another solar system. Bromley and Kenyon predicted locations in our solar system where captured objects would be, based on the angle and shape of their orbits. Finding captured objects in the predicted locations would be “proof that a flyby occurred,” says Bromley. He hopes astronomers will look more closely at sections of the sky where he and Kenyon predict alien planets might be.

Between 30 and 50 astronomical units from the sun – that is, 2.8 billion to 4.7 billion miles from the sun – several Kuiper belt objects larger than 600 miles in diameter are known to orbit the sun. Sedna, discovered in 2003, is similar to these cold, rock-and-ice worlds, but orbits 70 to 1,000 astronomical units from the sun. It has a high-inclination orbit, whic

Image by Image Editor via Flickr

h means it does not travel around the sun in the same plane as the major planets. Sedna’s orbit also is highly elliptical or elongated.

What caused Sedna’s elongated orbit? Answering this question was a key goal of Bromley and Kenyon’s study. Their simulations show there is a 5 percent to 10 percent chance Sedna formed within our solar system, probably closer to Neptune or Pluto, and was later launched into its current orbit when our solar system was “buzzed” by another.

Bromley says it is possible Sedna is an alien planet, formed in a solar system that later flew near our own. Bromley and Kenyon’s simulations suggest that there is a 1 percent chance that Sedna is a planet captured during a stellar flyby.

The Kuiper belt ends abruptly at 50 astronomical units from the sun and “there is no evidence that the hard edge of the Kuiper belt is in any sense natural,” says Bromley.

If the edge of our solar system were unperturbed, scientists would predict a gradual tapering of debris at increasing distances from the sun. The computer simulations showed that a close encounter with another solar system could explain why rocky, icy Kuiper belt objects vanish abruptly at 50 astronomical units.

Does the solar system face another destructive encounter with a neighbouring star? Not according to Bromley, who says the chance of that happening is “effectively nil” because the sun no longer is close to other stars in a cluster as it once was.

New concept car - BMW Vision EfficientDynamics

2009-09-30T03:10:00.000-07:00

The official world premier will take place this month at the Frankfurt Motor Show.
BMW will never fail to surprise me because every time they introduce a new car it is always a masterpiece.

The new BMW Vision is a hybrid car that has 2 electric motors and a three-cylinder turbo-diesel engine. The total capacity is of 356 HP. The car can reach 100 km/h in only 4.8 seconds. And the best about this hybrid is the fuel consumption – no more than 3,76 liters for 100 km. Incredible! Love this car.

First up is a slick 356-horsepower all-wheel-drive plug-in diesel-hybrid concept that BMW claims accelerates like an M3, sips gas like a Toyota Prius and can go 31 miles on battery power alone. It’s called the Vision Efficientdynamics Concept, and we’ll see it later this month at the Frankfurt auto show.

No, Vision Efficientdynamics Concept doesn’t exactly roll off the tongue. But the name aside, BMW has a dynamite idea on its hands here.

The EfficientDynamics is a 2+2 four-door hybrid that combines M Series performance with better fuel efficiency and less emissions than you see in many compacts. BMW performs this magic by marrying its ActiveHybrid technology with an extremely economical engine and excellent aerodynamics. The result is a concept car with a top speed governed at 155 mph and a zero-to-62 acceleration time of 4.8 seconds. More impressive, the car gets 62.2 mpg and emits a Prius-like 99 grams of CO2 per kilometer.

Power comes from a 1.5-liter direct injection 3-cylinder turbodiesel engine and an electric motor on each axle. The engine was small to squeeze in between the rear seat and the rear axle, which should make the Efficientdynamics Concept very agile. The diesel puts out 163 horsepower and 214 pound-feet of torque. Add in the motors and total output is 356 ponies and a stump-pulling 590 pound-feet, though you can only get that much power in short bursts. The car has all-wheel-drive when running in electric mode. BMW says the car can run on the diesel engine, either one of the electric motors or any combination of the three.

The lithium-polymer battery pack sports 98 cells. It delivers 8.6 kilowatt-hours for driving the car, and BMW says the serial arrangement of cells has gross storage capacity of 10.8 kilowatt-hours. The pack weighs 187 pounds and BMW says it doesn’t need an active cooling system. BMW says the battery recharges in 2.5 hours at 220 volts.

All that tech is housed in a body designed with some serious inspiration from BMW’s Formula 1 cars. BMW says the Vision has a drag coefficient of 0.22, aided in part by the myriad vanes and ducts. People are going to love it or hate it, but you’d expect nothing less from BMW even without controversial designer Chris Bangle around anymore.

So far the Vision is just a concept. Still, BMW has made it clear it plans to make sustainability a cornerstone of its lineup, so we’re sure to see some of the technology in road cars before long.

Is there ice on the Moon?

2009-09-24T15:56:00.000-07:00

On 5 March 1998 it was announced that data returned by the Lunar Prospector spacecraft indicated that water ice might be present at both the north and south lunar poles, in agreement with Clementine results for the south pole reported in November 1996. Later work has called this interpretation into question, so the issue is still unresolved. The ice originally appeared to be mixed in with the lunar regolith (surface rocks, soil, and dust) at low concentrations conservatively estimated at 0.3 to 1 percent. Subsequent data from Lunar Prospector taken over a longer period has indicated the possible presence of discrete, confined, near-pure water ice deposits buried beneath as much as 18 inches (40 centimeters) of dry regolith, with the water signature being stronger at the Moon's north pole than at the south (1). The ice was thought to be spread over 10,000 to 50,000 square km (3,600 to 18,000 square miles) of area near the north pole and 5,000 to 20,000 square km (1,800 to 7,200 square miles) around the south pole, but the latest results show the water may be more concentrated in localized areas (roughly 1850 square km, or 650 square miles, at each pole) rather than being spread out over these large regions. The estimated total mass of ice is 6 trillion kg (6.6 billion tons). Uncertainties in the models mean this estimate could be off considerably.

How was the ice detected?

The Lunar Prospector, a NASA Discovery mission, was launched into lunar orbit in January 1998. Included on Lunar Prospector is an experiment called the Neutron Spectrometer. This experiment is designed to detect minute amounts of water ice at a level of less than 0.01%. The instrument concentrated on areas near the lunar poles where it was thought these water ice deposits might be found. The Neutron Spectrometer looks for so-called "slow" (or thermal) and "intermediate" (or epithermal) neutrons which result from collisions of normal "fast" neutrons with hydrogen atoms. A significant amount of hydrogen would indicate the existence of water. The data show a distinctive 4.6 percent signature over the north polar region and a 3.0 percent signature over the south, a strong indication that water is present in both these areas. The instrument can detect water to a depth of about half a meter.

How can ice survive on the Moon?

The Moon has no atmosphere, any substance on the lunar surface is exposed directly to vacuum. For water ice, this means it will rapidly sublime directly into water vapor and escape into space, as the Moon's low gravity cannot hold gas for any appreciable time. Over the course of a lunar day (~29 Earth days), all regions of the Moon are exposed to sunlight, and the temperature on the Moon in direct sunlight reaches about 395 K (395 Kelvin, which is equal to about 250 degrees above zero F). So any ice exposed to sunlight for even a short time would be lost. The only possible way for ice to exist on the Moon would be in a permanently shadowed area.

The Clementine imaging experiment showed that such permanently shadowed areas do exist in the bottom of deep craters near the Moon's south pole. In fact, it appears that approximately 6000 to 15,000 square kilometers (2300 to 5800 square miles) of area around the south pole is permanently shadowed. The permanently shadowed area near the north pole appears on Clementine images to be considerably less, but the Lunar Prospector results show a much larger water-bearing area at the north pole. Much of the area around the south pole is within the South Pole-Aitken Basin (shown at left in blue on a lunar topography image), a giant impact crater 2500 km (1550 miles) in diameter and 12 km deep at its lowest point. Many smaller craters exist on the floor of this basin. Since they are down in this basin, the floors of many of these craters are never exposed to sunlight. Within these craters the temperatures would never rise above about 100 K (280 degrees below zero F) . Any water ice at the bottom of the crater could probably exist for billions of years at these temperatures.

Where did the ice come from?

The Moon's surface is continuously bombarded by meteorites and micrometeorites. Many, if not most, of these impactors contain water ice, and the lunar craters show that many of these were very large objects. Any ice which survived impact would be scattered over the lunar surface. Most would be quickly vaporized by sunlight and lost to space, but some would end up inside the permanently shadowed craters, either by directly entering the crater or migrating over the surface as randomly moving individual molecules which would reach the craters and freeze there. Once inside the crater, the ice would be relatively stable, so over time the ice would collect in these "cold traps", and be buried to some extent by meteoritic gardening. Such a possibility was suggested as early as 1961 . However, loss of ice due to photodissociation, solar wind sputtering, and micrometeoroid gardening is not well quantified .

Is there any other evidence for ice?

In a Science magazine article on 29 November 1996, it was announced that interpretation of data from a Clementine spacecraft experiment suggested the possibility of ice on the surface of the Moon. The ice was believed to be in the bottom of a permanently shadowed crater near the Moon's south pole (at the center of the Clementine mosaic shown at the top of the page). It was also thought likely that other frozen volatiles, such as methane, were in the deposit. The deposit was estimated to be approximately 60,000 to 120,000 cubic meters in volume. This would be comparable to a small lake in size, four football fields in surface area and 16 feet deep. This estimate was very uncertain, however, due to the nature of the data.

One of the problems in studying a permanently shadowed area is that no pictures can be obtained. The Clementine spacecraft searched for the ice using an investigation known as the Bistatic Radar Experiment. Basically, this experiment consisted of having the Clementine spacecraft transmit an S-band radio signal through its high gain antenna towards a lunar target. The signals reflected off the Moon and were received by a 70 meter Deep Space Network (DSN) antenna on the Earth. Frozen volatiles such as water ice are much more reflective to S-band radio waves than lunar rocks. Radio waves also have different characteristics when reflected off ice than off silicate rock. An analysis of the signals returned from orbit 234 showed reflection characteristics suggestive of water ice for the permanently shadowed areas near the south pole. Reflections from regions which are not permanently shadowed do not show these characteristics. It is possible that other scattering mechanisms could be responsible for this result, but the interpretation of the radio returns and the fact that they are associated only with the permanently shadowed regions seem to indicate that water ice is the most likely possibility. However, Arecibo radio telescope studies using the same radio frequency as Clementine showed similar reflection patterns from areas which are not permanently shadowed. These reflections have been interpreted as being due to rough surfaces, and it was suggested that the Clementine results may have been due to roughness, rather than water ice, as well.

Bistatic Radar Experiment Parameters
9-10 April 1994
Transmission: S-Band 2.273 GHz (13.19 cm wavelength)
Polarization: Right Circular (RCP)
Signal Power: 6 Watts
Axial Tilt: 4.5 to 5.5 degrees (Moon to Earth)
Orbits Used: 234 and 235

Why is ice on the Moon important?

The ice could represent relatively pristine cometary or asteroid material which has existed on the Moon for millions or billions of years. A robotic sample return mission could bring ice back to Earth for study, perhaps followed by a human mission for more detailed sampling. The simple fact that the ice is there will help scientists constrain models of impacts on the lunar surface and the effects of meteorite gardening, photodissociation, and solar wind sputtering on the Moon. Beyond the scientifically intriguing aspects, deposits of ice on the Moon would have many practical aspects for future manned lunar exploration. There is no other source of water on the Moon, and shipping water to the Moon for use by humans would be extremely expensive ($2,000 to $20,000 per kg). The lunar water could also serve as a source of oxygen, another vital material not readily found on the Moon, and hydrogen, which could be used as rocket fuel. Paul Spudis, one of the scientists who took part in the Clementine study, referred to the lunar ice deposit as possibly "the most valuable piece of real estate in the solar system". It appears that in addition to the permanently shadowed areas there are some higher areas such as crater rims which are permanently exposed to sunlight and could serve as a source of power for future missions.

In contrast to some recent claims, this debate is still open and nothing has occurred in the last few years to cause participants in the debate to abandon their positions. In a nutshell, poor or incomplete coverage by a variety of marginal data has led to much heat, while casting little light on the issue of lunar polar water. Here, I present the evidence to the reader, noting the strengths and weaknesses of each data set, and attempt to identify the remaining unanswered questions.

Clementine bistatic radar. As the Clementine spacecraft orbited the Moon, it transmitted radio waves toward the poles and we listened to the reflected radio waves bounced back to Earth. This experiment was bistatic, i.e., the transmitter and receiver were in different places. Bistatic radar has the advantage of observing reflections through the phase angle, the angle between transmitted and received radio rays. This phase dependence is important. It’s similar to the effect one gets from looking at a bicycle reflector at just the right angle: at certain angles, the internal planes in the transparent plastic align and a very bright reflection is seen. Similarly, in both radio and visible wavelengths on the Moon, we see an “opposition surge”, an apparent increase in brightness looking directly down from the sun (zero phase). Clementine orbited the Moon such that we could observe its phase dependence and we specifically looked for this “opposition surge”, called the Coherent Backscatter Opposition Effect (CBOE). CBOE is particularly valuable to identify ice on planetary surfaces.

Clementine transmitted right circular polarized (RCP) radio and we listened on Earth in both right- and left-circular polarized (LCP) channels. The ratio of power received in these two channels is called the circular polarization ratio (CPR). The dry, equatorial Moon has CPR less than one, but the icy satellites of Jupiter all have CPR greater than one. We know these objects have surfaces of water ice; in this case, the ice acts as a radio-transparent media in which waves penetrate the ice, are scattered and reflected multiple times, and returned such that some of the waves are received in the same polarization sense as they are sent—they have CPR greater than unity.

The problem with CPR alone is that we can also get high values from very rough surfaces, such as a rough, blocky lava flow, which has angles that form many small corner reflectors. In this case, a radio wave could hit a rock face (changing RCP into LCP) and then bounce over to another rock face (changing the LCP back into RCP) and hence to the receiver . This “double-bounce” effect also creates high CPR in that “same sense” reflections could mimic the enhanced CPR one gets from ice targets.

Bistatic geometry can help in the interpretation of radar scattering. Both monostatic and bistatic radar measure CPR but bistatic radar also measures the angular dependence on reflection, which is distinctly narrower for volume (ice) scattering. In the case of the Clementine experiment, we measured two orbits of the lunar south pole, one over an area of polar darkness and the other over a nominally sunlit zone near the pole. The results are intriguing; we see evidence of a CPR enhancement (symmetric about the zero phase angle; see peak in orbit 234 curve) over the dark region, where ice would be stable, but not over the control (orbit 235) sunlit area. The Clementine team interpreted this response as CBOE, caused by ice in dark areas near the south pole. From the strength of the enhancement and its angular width, they reasoned that ice was mixed with regolith dirt and present in a deposit about 2 meters thick with an average concentration of about 1.5 wt. %. It should be noted that this doesn’t require an intimate mixture of ice and dirt, but is the average over hundreds of square kilometers. Thus, areas could exist of nearly pure ice in some places, and virtually none elsewhere.

This conclusion was tempered by the recognition that Clementine found enhanced CPR only during one observation; the limited time of the mission at the Moon (71 days) precluded repeating that measurement. In addition, the Clementine spacecraft was not optimized for this experiment, so the data have very low resolution—basically a spot about 300 kilometers across. Nevertheless, the results of this experiment have not been refuted. The most recent Earth-based radar studies confirm that high CPR does indeed exist within the dark area near the south pole. Given the size of the Clementine resolution cell, the observed CPR enhancement could be explained by the same area of high CPR observed in groundbased radar images of the crater Shackleton. The controversy is not whether an area of high CPR exists in the permanently shadowed interior of Shackleton crater, but over what is causing the high CPR signature.

Lunar Prospector Neutron Spectrometer. NASA’s Lunar Prospector spacecraft carried an instrument that measured neutrons emitted from the Moon as a function of their energy. Medium-energy neutrons are strongly absorbed by hydrogen. Thus, by measuring the flux of neutrons in this energy range, we can estimate how much hydrogen is present in the lunar soil. The LP neutron experiment sampled only the upper 40 centimeters or so of the Moon. As the spacecraft was a spinner, its instruments looked simultaneously in all directions and the effect of such a view is to limit surface resolution to roughly the altitude of the spacecraft. The best resolution of the LP neutron data is 30–40 kilometers. Unlike both the Clementine radar experiment and Earth-based radar, the LP instrument looked directly into the entire polar dark area of the Moon.

The Lunar Prospector observed strong absorption of medium-energy neutrons at both poles. Initially it was thought that there was more hydrogen at the north pole, but later analysis showed roughly equal amounts at both poles. The actual enrichment (up to 200 parts per million) is only about a factor of two greater than the highest concentrations of solar wind hydrogen seen in the Apollo soil samples. But the LP team suggested that if this hydrogen was present as water ice (which is stable only in polar dark areas), the average concentration of ice was around 1.5 wt. %, a significant value. Moreover, with the low resolution of the LP neutron data, significantly higher concentrations within the shadow cannot be ruled out; a uniform, low average ice concentration of about 1–2 wt.% or a very heterogeneous distribution with very high concentrations (in some places up to over 40 wt.%) are equally consistent with the data.

Lunar Prospector neutron spectrometer maps of the lunar poles. These low resolution data indicate elevated concentrations of hydrogen at both poles; it does not tell us the form of the hydrogen. Map courtesy of D. Lawrence, Los Alamos National Laboratory.

Curiously, data from fast neutrons detected by Lunar Prospector suggest that the uppermost surface is depleted in hydrogen, down to about 10 centimeters below the surface. Such a depletion suggests a non-solar wind origin for the polar hydrogen, as hydrogen implanted by solar wind would be expected to be high in the uppermost lunar surface.

As you might expect, the LP neutron results have been questioned. Some have suggested that the reduction in neutrons is caused by the presence of another light element, such as sulfur. However, cometary ice is very abundant and known to constantly hit the Moon. Lunar sulfur is not rare, but is relatively low in cosmic abundance and any process that would concentrate sulfur in the polar dark areas would also concentrate the more abundant extra-lunar hydrogen. Recent claims that the LP neutron data indicate a low, uniform concentration are not correct; we know nothing about the distribution of the hydrogen below the resolution of the neutron spectrometer (i.e., scales smaller than 30 kilometers.)

Earth-based radar data. Radar has been used to study the Moon for decades with many observations made in preparation for the Apollo missions. This work largely concentrated on the equatorial regions (target sites for Apollo), but later work has focused on the lunar poles. Although some of their early work supported the concept, the most strident objections to the presence of lunar polar ice has come from planetary radar astronomers.

Nick Stacy mapped the south pole of the Moon using the Arecibo telescope in 1992 for his Ph.D. dissertation. The Arecibo group found several zones of high CPR, although its distribution is patchy and discontinuous. They noted that some areas of high CPR occur within craters that might be permanently shadowed (at that time, lighting maps of the poles did not exist). Although couched in appropriately cautious terms, Stacy noted that one high CPR zone occurs within the crater Shackleton and that it appears to continue down into the portion of the crater floor in Earth shadow, out of view of the Arecibo dish. Attributing most of the high CPR to blocky, rough surfaces associated with craters, Stacy reserved the possibility that some high CPR spots could be ice if they occurred deep within permanently dark crater floors.

Subsequent work by the Arecibo group has moved away from this cautiously positive interpretation to a definitive assertion that none of the high CPR zones seen around the pole are caused by the presence of ice. In at least four papers published between 1997 and 2006, they have presented increasingly more detailed image data, each showing the same relations: patchy, high CPR found in both sunlight areas and in permanent darkness. The latest paper from the Arecibo group, published in October 2006 to a barrage of publicity (including an overwrought press release in which one investigator called the “door on the debate” on lunar polar ice detected by radar “closed”) shows the south pole of the Moon in unprecedented surface resolution, about 20 meters per pixel. Yet again, we see the high CPR patch in Shackleton , but this time, it is accompanied by an image and analysis of another crater, Schomberger G, which is alleged to have the same distribution of high CPR within it. As Schomberger G is in sunlight (and has high CPR in portions of its interior), the authors conclude that the high CPR in Shackleton is similarly caused by surface roughness and not by the presence of ice within the permanently dark area of the crater.

As all parties agree that high CPR is found in the polar regions of the Moon, the debate is over what this relation means. The Arecibo group claims that the distribution patterns in Schomberger G and Shackleton are the same; hence, the high CPR patches represent rocky outcrops on and within these craters, not ice. However, high CPR can be caused by either roughness or ice; in itself, high CPR is not uniquely diagnostic of either . I contend that because of its non-unique nature, high CPR within Shackleton could be ice; as near as can be determined, the high CPR patch occurs within a zone of permanent darkness.

Why even entertain this notion? After all, if ice is unstable on any part of the Moon that sees sunlight, doesn’t that mean that high CPR here indicates roughness, not ice? In fact, similar relations are seen on the planet Mercury . The polar features of Mercury were initially discovered by Dewey Muhleman and colleagues at Caltech using very low resolution, global disk images. Although these images show a prominent high CPR zone near the north pole of Mercury , they also show high CPR zones in mid-latitudes and equatorial regions. The interpretation of the authors of this work was that two mechanisms produce high CPR on Mercury; near the equator, surface roughness must be the cause of high CPR, but at the poles, water ice in permanent shadow could not ruled out (like the Moon, Mercury’s pole is normal to the plane of its orbit around the sun). Thus, two scattering mechanisms were invoked. In principle, there is no reason why such a relation would not also occur on our Moon. In such a case, high CPR can be caused by both roughness and ice. If a spot is in sunlight, it must be surface roughness, but if it’s in the permanent darkness, ice cannot be ruled out.

It is claimed by the Arecibo group that the distribution of high CPR within the two craters Shackleton and Schomberger G are identical. As Schomberger G is in partial sunlight, high CPR seen within it cannot be caused by ice. As a planetary geologist, I see significant differences in the distribution of CPR in the two craters. In Schomberger G, high CPR is found as a quasi-continuous upper “layer,” with CPR values decreasing deeper into the crater. At Shackleton, the upper crater wall is complex and high CPR is discontinuous; the large zone of high CPR within the crater at about 8 o’clock starts below the rim, but continues down into the crater, disappearing into the shadow caused by the Earth-Moon geometry. I leave it to readers to decide for themselves whether the distribution of high CPR is identical in these two craters. All of the interior of Shackleton is in permanent darkness, shielded from sunlight and has been continuously for at least the last two billion years. So in theory, ice may have accumulated within it. Thus, three data sets exist, each unique, on the possibility of lunar polar ice. But what are they telling us?

Synthesis: Best guess on polar volatiles

No single piece of evidence for lunar ice is decisive, but I think the preponderance of evidence indicates that water ice exists in permanently dark areas near the poles. However, its origin and the processes associated with its deposition are unclear. The ice could be of cometary, meteoritic, or solar wind origin; each mode would have interesting implications for its composition. If largely of cometary origin, other volatile species of great utility may also be present, such as ammonia (NH3), methane (CH4), and various organic substances. Nitrogen is particularly useful in supporting human life, both for breathing air and for agriculture. Whatever the source, polar ice is a useful resource for future lunar inhabitants.

Much remains unclear about the nature of ice is on the Moon. Rates of deposition of polar ice and implications for its physical nature are unknown. We can, however, make some inferences from the data in hand. Ice deposits cover a minority of the polar terrain and concentrations of it could vary widely over a small area, leading to a very heterogeneous deposit. This supposition is suggested by the patchy distribution of high CPR spots in the Earth-based radar data (not all of which are caused by ice). The concentration and distribution of the ice is unknown, but if very heterogeneous as suggested, deposits could locally cover between 10–50 percent of a given patch of dark area. Individual bodies of trapped ice could be on the order of meters to tens of meters in size, as suggested by the patchy extent of high CPR areas seen in the polar darkness.

From the fast neutron data of Lunar Prospector, the uppermost 10 centimeters or so of the polar dark regions are depleted in hydrogen. Radar data suggest volume scattering at depths on the order of several tens of wavelengths of the S-band radar (~13 centimeters). Thus, ice occurs between depths of 10 centimeters and 2–3 meters. From our current understanding of the creation, turnover, and evolution of the lunar soil, the ice is probably not “pure” but contains contaminants and solid inclusions of varying concentrations. Although water ice is expected to dominate the deposit, other minor species of cometary origin could be present in useful quantities. The terrain of a lunar highlands region (found at both lunar poles) can be very rugged, with local slopes exceeding 30 degrees. However, as shown by the Apollo 16 highland landing site, such areas can be negotiated reasonably well, if the correct paths are chosen.

So what?

Water ice on the Moon makes living there easier, cheaper, and thus, more likely. Solar wind hydrogen is found everywhere on the Moon, but in vanishingly small quantities. Ice at the poles is a concentrated source of both hydrogen and oxygen—two substances vital to supporting human life and creating a space transportation infrastructure. We can extract what we need out of the equatorial regolith, but it’s much harder and more energy intensive than at the poles. Extracting solar wind hydrogen requires heating soil to about 700° C, at which point 90 percent of the adsorbed gas is driven off. In contrast, icy regolith heated to about 100° C gives off water as an easily collected and stored gas. Per unit mass, it takes roughly two orders of magnitude less energy to extract hydrogen from icy polar regolith than it does by roasting soil at the equator.

Although polar ice is important, it is not a requirement to successfully live and work on the Moon. The poles of Moon are primarily attractive due to the near-permanent sunlight found in several areas. Such lighting is significant from two perspectives. First, it provides a constant source of clean power and allows humans to live on the Moon without having to survive the two-week-long lunar night experienced on the equator and at mid-latitudes. Second, because these areas are illuminated by the Sun at grazing angles of incidence, the surface never gets very hot or very cold. Sunlit areas near the poles are a benign thermal environment, with an estimated temperature of about –50° ± 10°C. Having water near these locales would be a huge bonus. The most compelling reason to go to the poles is to solve the problem of surviving the extended lunar night—a task that, at most other places on the Moon, would probably require spending billions of dollars for a nuclear reactor.

Science is an imperfect process. At any given point in time, we have limited data of less than optimum quality and nearly always imperfectly or incompletely understood. Our information on lunar polar ice is limited in both quality and quantity. No question in modern science is “solved” and the presence of “consensus,” while a useful concept in marketing and politics, has no real value to the truth or falsity of scientific questions. The way the universe is put together and works is quite independent of the collective opinions of the experts.

To answer the question of lunar polar ice, we need more and better data. We must first thoroughly map the polar deposits from lunar orbit. India is preparing to launch their first mission to the Moon, Chandrayaan-1, in early 2008. I am on a team that will build and fly the radar mapping instrument on that mission. This radar will map both poles using a revolutionary new processing architecture that allows us to distinguish areas of high CPR caused by roughness and those caused by the presence of ice. An even more advanced radar instrument will be on the US Lunar Reconnaissance Orbiter (LRO) mission in late 2008, mapping in two frequency bands (potentially distinguishing roughness from ice) and in high resolution, showing patches of ice as small as 20 meters across. Chandrayaan will systematically map the polar regions at moderate resolution (75 meters/pixel.) On the subsequent LRO mission, we will get high-resolution coverage (10 meters/pixel) at multiple wavelengths of promising targets seen in that data. Since these two missions overlap and will orbit the Moon at the same time, we can use both instruments on the two spacecraft to make bistatic images of the polar deposits; such a mode of operation can observe scattering through the phase angle (looking for the CBOE effect, a good discriminator between ice and roughness). Together, these missions will map the extent and distribution of anomalous material in the polar regions of the Moon.

A key advantage of orbital mapping is the ability to look into all of the areas of permanent darkness. In a recent article in Scientific American (“Radar Images Fail to Detect Ice at Lunar Poles”, October 2006), Don Campbell of Cornell University, part of the Arecibo team, notes that the lunar orbiters LRO and Chandrayaan “will get a better view of the polar terrain than we can from Earth.”

The LRO spacecraft will carry other instruments, including a thermal mapper to determine temperatures of the dark areas, a laser altimeter to measure the topography of the poles (needed to make definitive maps of sunlight and darkness) and other instruments designed to characterize the environment and deposits of the polar regions. In addition, other nations (including China and Japan) are flying lunar orbiters carrying a variety of mapping instruments. The Moon, once the most poorly mapped body in the Solar System, appears ready to become the most thoroughly charted and remotely studied object in the history of mankind.

The next step is critical. After polar deposits have been mapped from orbit, we must land at a promising target and measure volatile substances in the soil. As descri

Image via Wikipedia

bed above, no matter what high-quality remote sensing data we obtain, there is always ambiguity in interpreting remote sensing data. We must have ground truth. Going into the polar darkness, digging up the soil, and measuring what’s there will finally answer, in a definitive manner, the nagging question we started with: Is there ice on the Moon?

After the first lander, we should survey potential mining prospects, map the distribution of ice on small, local scales (hundreds of meters), and experiment with different extraction methods, water separation technologies, and resource processing and storage techniques. The goals of lunar resource utilization are challenging, but significant experience can be gathered from small robotic landers prior to the arrival of people. A program of robotic missions can provide critical strategic information as well as gaining operational experience and providing milestones for a human lunar return.

The Moon is not a hostile, barren rock in space—it is humanity’s stepping-stone into the Solar System. The poles of the Moon are inviting “oases” for humans in the desert of near-Earth space. To live there and at destinations beyond, we must identify resources that will support human life and enable the creation of a new spacefaring infrastructure.

Moon Water

2009-09-24T15:43:00.000-07:00

The moon is a lot wetter than we thought. That’s the conclusion of scientists who used data gathered by India’s first lunar mission to determine there may be widespread moisture locked in lunar soils.

The upper few millimeters of the moon’s surface contains molecules of water, or H2O, and hydroxyl (OH) -- an indication that water formation may be an ongoing process at the moon’s surface, the researchers said today in the journal Science.

“When we say ‘water on the moon,’ we are not talking about lakes, oceans or even puddles,” the study’s lead author, Carle Pieters, a planetary geologist at Rhode Island’s Brown University, said. “Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon’s surface.”

The findings open the way for astronauts on lunar missions to harvest water from the moon’s surface, according to the paper. The National Aeronautics and Space Administration on June 18 launched two probes to search for frozen water on the moon.

Discovering the substance would be like finding a goldmine, the agency said at the time, putting the cost of transporting a bottle of water to the moon at $50,000.

“NASA wants to set up a permanent base on the moon, and they want to live off the land,” Colin Pillinger, professor of planetary science at the U.K.’s Open University in Milton Keynes said today in a phone interview. “To do that, they need water.”

Polar Ice

Pillinger, who this year co-wrote a study for NASA about extracting water and other compounds from the lunar surface, said that physical samples will be needed to prove the conclusions from today’s study, and that extracting water will be a challenge.

“Technically it’s easy, but logistically it’s awfully difficult because it takes a lot of energy,” Pillinger said. “If you want a long-term lunar base, then you go to the poles,” because no refrigerator will be necessary to condense water vapor that has been boiled out of the soil, he said.

Craters at the lunar poles haven’t been exposed to sunlight in billions of years and probably have temperatures of minus 328 degrees Fahrenheit (-200 degrees Celsius), according to NASA. That has led planetary scientists to theorize water ice may be present in those dark areas.

As many as 770 water molecules could be present in every million molecules in the thin top layer of the moon’s soil, according to today’s paper. Brown University said in a statement the proportion could be as high as 1,000 per million. The data was gathered by the Moon Mineralogy Mapper instrument aboard India’s Chandrayaan-1 craft.

Moon’s Topsoil

The researchers concluded the most likely origin of the water is as a result of the so-called solar wind, laden with charged hydrogen particles, impacting with the oxygen-rich lunar soil.

The mapper instrument, called M3, analyzed the way sunlight reflects off the lunar surface to determine the materials that constitute the soil, according to a statement from the University of Tennessee at Knoxville, which participated in the study.

Crashed Probe

NASA’s Lunar Prospector craft in 1998 detected hydrogen near the pole, prompting speculation that water was present. A year later, the agency deliberately crashed the craft into the moon’s surface, hoping to detect water vapor in the resulting dust plume, without success.

Trace amounts of water detected in rocks shipped back from the moon by Apollo missions 40 years ago were attributed to contamination from the Earth’s air because the boxes housing the samples had leaks, according to the University of Tennessee.

“The isotopes of oxygen that exist on the moon are the same as those that exist on Earth, so it was difficult if not impossible to tell the difference,” Larry Taylor, a co-author of today’s paper, said in the university’s statement. “Since the early soil samples only had trace amounts of water, it was easy to make the mistake of attributing it to contamination.”

Last year, researchers at Brown analyzed volcanic glasses recovered by the Apollo 15 mission, finding evidence of water, which they said must have had its origins deep inside the moon.

The Indian “moon craft” was designed to orbit the moon for two years at an altitude of 100 kilometers (62 miles). Scientists in the southern Indian city of Bangalore lost contact with it on Aug. 29 after 315 days in orbit.

How to Build a Nuclear Bomb

2009-09-23T17:33:00.000-07:00

The easy part

There is more than enough information out there explaining how to produce a nuclear weapon. This became obvious in 1967 after three newly minted physics professors with no nuclear weapons experience were able to draw up a credible design for a nuclear bomb. The physicists had been hired by researchers at Lawrence Livermore National Laboratory to assess the difficulty of producing a nuclear weapon, a project known as the Nth Country Experiment. Russia was the second nation to develop nuclear weapons after the United States. So the question was: Who would be the Nth country?

However, acquiring the necessary materials to fuel the bomb, such as weapons-grade uranium, proved to be difficult at the time.

Weapons-grade uranium, or isotope U-235, is a highly unstable form that makes up less than 1 percent (.7 percent) of the concentration of uranium ore that is dug up. The Federation of American Scientists estimates that uranium needs to be refined to a concentration of at least 80 percent U-235 to be weapons grade, though upwards of 90 percent is preferable.

Other significant hurdles remain, related to everything from enriching the material, to building a successful detonation device, to delivering it all with conventional missiles that may not be able to carry the extra weight of a nuclear warhead.

Enriching uranium

A popular way of achieving weapons-grade uranium is by using a gas centrifuge process, whereby a converted gaseous form known as uranium hexafluoride is released into a spinning cylinder. The force generated by the rotating cylinder separates U-235 isotopes from the heavier U-238 isotopes.

U-235 differs from U-238 in that it can undergo an induced fission chain reaction, a process that begins with using a subatomic particle known as a neutron to split the atom of a radioactive material like uranium into smaller pieces. The destructive power of a nuclear bomb is unleashed when an atom that has been split ends up sending its neutrons slamming into other atoms and splitting them, which in turn creates the chain reaction.

The tricky part

In order to sustain the type of chain reaction necessary for a bomb explosion, the atoms need to be held in a modified state known as “supercritical mass” so that more than one of the free neutrons from each split hits another atom and causes it to split. A supercritical mass is formed in a uranium bomb by initially storing the fuel as separate subcritical masses to prevent the bomb from detonating too early, and then joining the two masses together. The bomb also needs to be designed to allow enough of the chain reaction to take place before the initial energy from the explosion causes the bomb to fail.

“Little Boy,” the first nuclear bomb that was dropped on Hiroshima during WWII, was fueled by uranium and detonated with a force equivalent to about 15 kilotons of TNT, killing as many as 140,000 people.

But a major problem with uranium bombs, is the fact that the material happens to be the world’s heaviest naturally occurring element (twice as heavy as lead). According to the Union of Concerned Scientists, a nuclear bomb needs about 33 pounds (15 kilograms) of uranium to be operational, a requirement that hinders how far a missile can travel. The bulkiness of uranium also makes it harder to mount the technology to existing missile systems.

A nuclear weapon fueled by plutonium would solve this problem since less of the material is required. The U.S. Department of Energy estimated that about 9 pounds (4 kilograms) of enriched plutonium or Pu-239 would be enough to build a small nuclear weapon, though some scientists believe that 2 pounds (1 kilogram) of plutonium would suffice.

Unlike uranium bombs, plutonium bombs are detonated using an “implosion” method, where enriched plutonium is kept in a ball-shaped chamber and surrounded by explosives. Once detonated, the force of the explosives sends a shock wave that momentarily compresses the material into a supercritical mass. A separate neutron source at the center is then released at just the right moment to trigger a chain reaction.

A lot of countries that develop the capability to make uranium bombs later get interested in plutonium bombs because you can fit them into smaller weapons and that allows you to achieve a much longer range with the missiles.

Plutonium's problems

Using plutonium to make a bomb presents its own difficulties, however. For instance, “you have to build a huge, expensive chemical processing facility that also happens to be very dirty to extract, purify and compress the plutonium so it would fit into a nuclear warhead."

Warheads are complicated little machines. “The entire detonation process happens within a tiny fraction of a second so the hard part is constructing a warhead with reliable separation capabilities throughout the various stages.”

Other challenges include developing a missile guidance system and, if the missile will soar into space en route to its destination, a re-entry body to house the warhead and protect it from the extreme temperatures encountered as it travels back into the atmosphere.

It’s not enough to have the enrichment capability to produce weapons grade uranium or plutonium. “There’s a real gap from the point where you can enrich something to a degree needed to where you are building a warhead and saying we now have that technology.”

Black beauty of the Year 2009

2009-09-22T04:02:00.000-07:00

GT550

Innovation at its Best - Google

2009-09-09T17:21:00.000-07:00

Smart Internet search will be able to do with a mobile device in the NEAR future
A mobile device with Touch screen, built in camera, scanner, WiFi, google map (hopefully google earth), google search, image search…

Like this way, when you can see a building through it, it gives you the image search result right on the spot.

Choose a building and touch a floor and it tells you more details of the building. You can use it when you want to know a car model, an insect name, what kind of food is served at a restaurant and how much, who built a bridge, etc. etc.

It's got a scanner built in.

so you can use it this way when you want to check the meaning of a word in the newspaper, book, magazine, etc. It would be much easier to read a real book. You can use the dictionary, wikipedia, thesaurus and anything else available on the web. What do you think?

Indoor guide:Works in a building, airport, station, hospital, etc.

Automatic simultaneous translation: here Latin to English.

Search keyword: Helpful when you want to find out a word from a lot of text in newspaper/book.

Nutrition: This kind of function would be helpful for health freaks..

Boeing 787 Dreamliner

2009-08-27T18:47:00.000-07:00

The 787-8 Dreamliner will carry 210 - 250 passengers on routes of 7,650 to 8,200 nautical miles (14,200 to 15,200 kilometers), while the 787-9 Dreamliner will carry 250 - 290 pas

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sengers on routes of 8,000 to 8,500 nautical miles (14,800 to 15,750 kilometers). A third 787 family member, the 787-3 Dreamliner, will accommodate 290 - 330 passengers and be optimized for routes of 2,500 to 3,050 nautical miles (4,600 to 5,650 kilometers).

Image by fox2mike via Flickr

In addition to bringing big-jet ranges to mid-size airplanes, the 787 will provide airlines with unmatched fuel efficiency, resulting in exceptional environmental performance. The airplane will use 20 percent less fuel for comparable missions than today's similarly sized airplane. It will also travel at speeds similar to today's fastest wide bodies, Mach 0.85. Airlines will enjoy more cargo revenue capacity.

Passengers will also see improvements with the new airplane, from an interior environment with higher humidity to increased comfort and convenience.
Advanced Technology

The key to this exceptional performance is a suite of new technologies being developed by Boeing and its international technology development team.

Boeing has announced that as much as 50 percent of the prim

Image by fox2mike via Flickr

ary structure - including the fuselage and wing - on the 787 will be made of composite materials.

An open architecture will be at the heart of the 787's systems, which will be more simplified than today's airplanes and offer increased functionality. For example, the team is looking at incorporating health-monitoring systems that will allow the airplane to self-monitor and report maintenance requirements to ground-based computer systems.

Boeing has selected General Electric and Rolls-Royce to develop engines for th

Image by Danny McL via Flickr

e new airplane. It is expected that advances in engine technology will contribute as much as 8 percent of the increased efficiency of the new airplane, representing a nearly two-generation jump in technology for the middle of the market.

Another improvement in efficiency will come in the way the airplane is designed and built. New technologies and processes are in development to help Boeing and its supplier partners achieve unprecedented levels of performance at every phase of the program. For example, by manufacturing a one-piece fuselage section, we are eliminating 1,500 aluminum sheets and 40,000 - 50,000 fasteners.

Continuing Progress

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The Boeing board of directors granted authority to offer the airplane for sale in late 2003. Program launch occurred in April 2004 with a record order from All-Nippon Airways. Since that time, 56 customers from six continents of the world have placed orders for 865 airplanes valued at $144 billion, making this the most successful launch

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of a new commercial airplane in Boeing's history. The 787 program opened its final assembly plant in Everett in May 2007.

The program has signed on 43 of the world's most capable top-tier supplier partners and together finalized the airplane's configuration in September 2005. Boeing has been working with its top tier suppliers since the early detailed design phase of the program and all are connected virtually at 135 sites around the world. Eleven partners from around the world completed facility construction for a total of 3 million additional square feet to create their major structures and bring the next new airplane to market.

LG Wrist Mobile

2009-08-13T18:05:00.000-07:00

LG GD910 Tick-tock, tick-tock

Introduction

If you see someone having a chat on their wristwatch you may decide they've lost contact with the mothership. Well, it beats us what you'd think when the mothership calls back. But maybe this little personality test will help us figure it out.

You find the idea of a video-call enabled wristwatch phone:
a) Cool
b) Fool-around cool
c) Downright mental
d) Man, not another Trekkie test!
e) Who cares as long as we make some buck out of it.

All right then, if you answered B, C or D it's pretty obvious you're not from LG. And hey, if you answered A, those who answered E will love to meet you.

Tick-tock, digital wristwatch phones are nothing new actually, but somehow we need to pull ourselves together and start taking them seriously. LG and Samsung do, so there must be something, right.

The LG GD910 for one is dead serious judging by that price tag they have there. Or shall we call it LG double O seven - not so much for the cloak-and-dagger form factor as for the license to kill your savings. Well, it does make some sense really: almost acceptable dimensions and all the basic phone features duly covered. Touchscreen, fast data and video calling on a wristwatch - go ahead and call it crazy but you'd still be interested.

So, let's check out that specs sheet then, shall we?
Key features:

* Wristwatch form factor with a leather strap
* Water splash resistant (we're still raising the 900 euro needed to test it)
* 1.43" capacitive touchscreen display with a resolution of 128 x 160 pixels
* Comes with a Bluetooth headset
* Excellent sunlight legibility
* Quad-band GSM/GPRS/EDGE support
* 3G with 7.2Mbps HSDPA and video-calling
* Bluetooth v2.0 with A2DP
* 2GB onboard storage
* Video call camera capable of making photos in VGA (640 x 480 pixels) resolution
* Flash UI, optimized for finger usage
* Text-to-speech enabled (no Klingon support as of yet)
* Voice commands
* Flight mode

Main disadvantages:

* See water resistance above
* Bulkier than even a large watch
* No way to expand the built-in memory
* Display colors and contrast are pretty washed out even in the dark
* UI is somewhat slow at times
* No FM radio
* Trekkies would rather go for a lapel phone

We bet some of those disadvantages you already knew, while the rest of them will receive their due explanation as the review unfolds. For now we'll just say we don't have a clue about the LG GD910 target audience so we're trying to cover up our embarrassment with lame jokes.

LG GD910 at ours

Anyway, while hardly any self-respecting geek will wear one, the LG wristwatch can still count on the geek's benefit of the doubt. We sure hope we don't live to review ear implants as the next in mobile phones but we guess we can handle a wristwatch. Let's see what it's got (and what it doesn't).
LG GD910 360-degree spin

It's really strange that LG went for a regular letter-number designation for their first watchphone. We would have expected marketing to come up with at least something more easy to remember such as the LG Crystal.
Design and construction

The LG GD910 is too big for a watch but then, impressively small for a phone. Take the strap away and you have an LG touchscreen Mini-Me. Truth be told, if you fancy watches with larger dials you might find the LG GD910 size just fine. The really troublesome bit is its thickness really. We do however acknowledge the engineering achievement of squeezing in a capacitive touchscreen, 3G and video calls on top of the basic calling and texting stuff in that compact body.

The LG GD910 next to a couple of regular watches

Perhaps the future efforts will be in reducing the bulging girth. We haven't actually seen the Samsung Samsung S9110 in person but it sure looks quite thinner than the LG wristwatch. The The Samsung timepiece is no match for the LG specs though - it's some video-calls short of a childhood dream gadget (though maybe we didn't all grow up watching the same cartoons).

Anyway, back to the GD910, there's a fully-functional handset hiding inside and that's its main point, not the geeky charm or fashion value.

The leather strap is pretty nice and simple (at least on poor pre-release unit) but that charming simplicity hardly matches the fancy digital dials that appear on the screen. We're glad that for the final retail version LG went for a more mature strap enhanced with a metal clasp to secure the device on your wrist.

The nice and simple strap on our pre-release unit • the LG final piece

The watch dial is actually a 1.43" 256K-color capacitive touchscreen with a resolution of 128 x 160 pixels. Its image quality is rather disappointing but to be honest we hardly expected otherwise given the specs.

The display size is rather limiting (especially for a touchscreen), which makes it quite a challenge to use comfortably at first, but we got used to it sooner than expected. Anyway, we guess it's a good balance in terms of comfort of use given the limitations of the form factor.

The only other things to note at the front are the earpiece and the VGA camera, which is used for video-calling.

The sunlight legibility was the first surprise of the GD910 screen. As one would expect from a watch it's perfectly visible in any lighting conditions, including bright sun. Also the capacitive technology used makes sure the display is pleasingly responsive.

The next surprise however was unpleasant. It may be due to our unit being pre-release and all, but we've hardly seen so poor colors and contrast on a mobile screen lately.

The right side of the LG GD910 is where its hardware controls are placed - typical watch style. The GD910 has a Call key, which doubles as menu button in most menus, the Clear/Back button and the End key. They're comfortable enough to use but you have to account for some limitations across the interface.

For example in the music player the back key is used for setting the volume, so there is no actual back button functionality there. Pressing the middle key in the music player or during a call launches an onscreen volume control which you finger sweep up and down. It works quite alright even of the LG GD910's tiny screen.

The bottom side of the watch has a steel cover which you rotate to unlatch. We guess there might be some kind of tool for the purpose in the retail package but a coin will also do though you risk to scratch the groove walls.

The battery cover fits quite firmly so it needs a hard push to release but this was to be expected in a water-proof watchphone. Under the cover is the SIM card compartment and that's about that. We are sorry to break it to you but the swapping the battery is not a DIY option. There's no way to expand the built-in memory as well.

Removing the LG GD910 back panel

The tour around the LG GD910 comes to a final stop at the metallic connectors at the bottom of the watchphone. To charge the battery you need to place the GD910 on the special cradle which takes in a proprietary LG charger or data cable. We guess a standard micro or miniUSB plug is too much to ask.

The general build quality of the LG GD910 is probably the best thing about the whole device. With nice looking and seemingly durable materials it looks set to last.

The GD910 worn on the wrist

Now let's move on and check out what the GD910 has on the inside. It's a small piece but that probably makes the user interface all the more important.

Robots In Photos

2009-08-13T16:24:00.001-07:00

Scientists, students and corporations continue their work around the world in the field of robotics, persistently improving and redefining their capabilities, interfaces and roles in society. Unmanned vehicles fly above war zones, telerobotics give humans a broader virtual presence and humanoid robots gain more parity with humans, refining their movements and responses. Collected here are a handful of recent photographs of robotics in use around the world.

Future with BioFuel

2009-07-21T15:47:00.000-07:00

Unlike their fossil fuel counterparts — the cadaverous remains of plants that died hundreds of millions of years ago — biofuels come from vegetation grown in the here and now. So they should offer a carbon-neutral energy source: Plants that become biofuels ideally consume more carbon dioxide during photosynthesis than they emit when processed and burned for power. Biofuels make fossil fuels seem so last century, so quaintly carboniferous.

And these new liquid fuels promise more than just carbon correctness. They offer a renewable, home-grown energy source, reducing the need for foreign oil. They present ways to heal an agricultural landscape hobbled by intensive fertilizer use. Biofuels could even help clean waterways, reduce air pollution, enhance wildlife habitats and increase biodiversity.

Yet in many respects, biofuels are in their beta version. For any of a number of promising feedstocks — the raw materials from which biofuels are made — there are logistics to be worked out, such as how to best shred the original material and ship the finished product. There is also lab work — for example, refining the processes for busting apart plant cell walls to release the useful sugars inside. And there is math. A lot of math.

The only way that biofuels will add up is if they produce more energy than it takes to make them. Yet, depending on the crops and the logistics of production, some analyses suggest that it may take more energy to make these fuels than they will provide. And if growing biofuels creates the same environmental problems that plague much of large-scale agriculture, then air and water quality might not really improve. Prized ecosystems such as rain forests, wetlands and savannas could be destroyed to grow crops. Biofuels done badly, scientists say, could go very, very wrong.

“Business as usual writ larger is not an environmentally welcome outcome,” states a biofuels policy paper authored by more than 20 scientists and published in Science last October.

Many scientists have expressed concern that political support for the biofuels industry has outpaced rigorous analyses of the fuels’ potential impacts. Others see this notion as manure. Research needed to resolve that disagreement is now underway, as scientists in industry, national labs and universities across the country are assessing every aspect of these fuels, from field to tailpipe. Researchers are growing crops, evaluating yields and comparing harvesting techniques. Computer models are providing stats on each crop’s effect on environmental factors such as soil nutrients and erosion. The plant cell wall is under attack from several angles. And chemists and microbiologists are cajoling an expanding menagerie of microorganisms into producing higher fuel yields.

Green goals

Ideally, high biofuel yields come with minimal environmental baggage and maximum efficiency at every step. The raw materials for these fuels run the gamut from corn to municipal waste to algae, and each has its own benefits and headaches. To make fuels, researchers must first process the raw material to create fermentable sugars or a crude oil-like liquid. Further refinement yields fuels such as ethanol, butanol, jet fuel or biodiesel.

In some cases, such as algae-based biodiesel, the technologies are far from mature. Squeezing ethanol from crops such as corn, on the other hand, uses a technology as old as whiskey. An infrastructure already exists for growing and moving grain, and distillation and fermentation techniques work at large scales.

But grain-based fuels raise several environmental issues, such as emissions of the potent greenhouse gas nitrous oxide from heavy fertilizer use. So, many scientists see corn ethanol as a bridging technology for use until the next-generation feedstocks fulfill biofuels’ real promise. Nonfood plants rich in cellulose or even residual waste diverted from landfills may define the biofuel future.

Several studies attest to the benefits of fuels made from such feedstocks, although the degree of benefit varies depending on what factors are included in the analysis. Overall, dedicated energy crops such as switchgrass and waste residues from sources like commercial logging fare better than corn-based ethanol, concludes a recent modeling analysis and literature review citing more than 100 papers. Published online May 27 in Environmental Science & Technology, the analysis reports that municipal waste-based ethanol production emits an estimated 60 to 80 percent less greenhouse gas than corn-based ethanol production. Dedicated energy crops, especially when grown on marginal land, also fare better than corn in terms of greenhouse gas emissions, and require less water and generate less air pollution, report researchers from the National Renewable Energy Laboratory in Golden, Colo., and E Risk Sciences in Boulder, Colo.

Biomass BenefitsView Larger Version | Greenhouse gas emissions drop, and air and water quality improve, when switchgrass and forest residues from logging replace corn as a raw material for fuel, suggests a recent life cycle analysis. The chart shows the improvement relative to corn for these two next-generation biofuel hopefuls.Williams et al./Environmental Science & Technology 2009

Research also suggests that these new fuels will be priced competitively with gasoline from petroleum. A new assessment coauthored by Lee Lynd, head scientist and cofounder of the Boston-based ethanol start-up Mascoma Corp., found that the production costs of cellulose-based ethanol, when made on a commercial scale, could be competitive with gasoline at oil prices of $30 or more per barrel.

Both of these recent big-picture studies, while optimistic, call for continued research to improve existing production processes and better define each fuel’s associated trade-offs.

Such research is in progress at the Idaho National Laboratory in Idaho Falls, where scientists David Muth Jr. and Thomas Ulrich take part in a coordinated, national effort to watch grass grow. In partnership with scientists at Oak Ridge National Laboratory in Tennessee and at several universities, Muth and Ulrich are keeping track of more than 50 field trials of various feedstocks across the country. The researchers are growing switchgrass and Miscanthus, an 11-foot tall perennial grass. Energy cane, an über-biomass relative of sugar cane, is also under study.

The research suggests that there is not one silver bullet source for biofuels. While there are some generally desirable plant characteristics — such as needing few nutrients and flourishing on degraded land — the future biofuels landscape will likely be a patchwork of different sources that work best in different regions.

Energy cane, for example, has “huge yields, but it is a water sink,” he says. So it may be best for water-rich Gulf Coast states. Miscanthus, which has been tested in Europe for several years, produces very high yields and has the genes to withstand cold climates.

Part of biofuels’ allure lies in the variety of ingredients from which the fuels may be spun. The Idaho National Lab is also investigating strains of algae that pump out oils as a raw material for biodiesel. At other sites agricultural and municipal waste, such as straw stalks, corn cobs and tree cuttings, are under investigation. Some researchers are focused on crops dedicated to energy, such as prairie grasses, and fast-growing softwoods, such as willow, poplar and eucalyptus. A pilot-scale system for growing the diminutive pond plant duckweed on wastewater is underway at North Carolina State University.

In Idaho, Muth is also using several computer models to calculate the effect that growing and removing the feedstocks has on factors such as soil’s nutrients, carbon and water content. This information, along with yields and quality of plant material, is all being entered into a database to help predict which plants will grow best where.

Biomass breakdown

Bioenergy is not just about growing crops up, though. It’s even more about tearing them down. Biomass must be harvested from the field or forest, perhaps stored, and then shipped to a refinery for processing. Harvesting equipment, travel distances and processing methods must all be considered to determine whether biofuels make economic and energy sense.

“What is becoming a bigger and bigger issue to people is the logistics of it all — that’s becoming a barrier to the whole thing,” says J. Richard Hess, the technology manager of the Idaho National Lab program.

Power from PlantsView Larger Version | Scientists are studying biofuels from the field to the pump to make each step more efficient and environmentally friendly. Here’s a typical blueprint for ethanol production.Newhouse Design

An essential part of biofuel logistics is the preprocessing of plants — cutting, baling and hauling the bales somewhere for storage before transporting them to a refinery. Those preprocessing steps pose problems with a material that isn’t very dense or evenly shaped. “It’s like moving air or feathers,” Hess says.

Ideally, preprocessing would provide an end product that is uniform and easy to handle, like grain — the biomass equivalent of crude oil. “We’re not aiming for a certain size, but a certain density that’s easy to ship, is flowable,” says INL’s Christopher Wright.

Wright and Neal Yancey, also of INL, are trying to achieve the optimal density by finding the right balance of shredding and compacting, ultimately producing something like the alfalfa pellets fed to pet rabbits, or perhaps Matchbox car–sized blocks. This crude can then be shipped to a refinery to be heated into an oil-like liquid or broken down by enzymes into the desired fuel.

Breaking biomass down into fuel is no small task. The dominant method is known as biochemical conversion: processes that use heat, chemicals or enzymes to turn the biomass into sugars that can be fermented by microbes such as yeast into ethanol. This ethanol is the same whether its origins are corn or other biomass. But it is currently a lot easier to get the fermentable sugars out of a starchy corn kernel than from something like wood chips or a weedy grass.

Plant cell walls are about 75 percent complex sugars, but getting at these sugars is a bit like trying to get the mortar and minerals out of a castle’s rampart. Cell walls, one of the defining features of plants as a life-form, were made to resist degradation. Even termites and cows need special microbes in their guts to get the job done.

That’s because those sugars are embedded in a complex architectural structure called lignocellulose — cellulose (long, unbranched chains of glucose) embedded in a matrix of more sugars (hemi-cellulose) embedded in the tough, gluelike lignin. (Biofuels researchers refer to the “recalcitrance” of the cell wall, as if it were an obstinate child.) Not only did cell walls evolve for strength, they also are a primary defense against microbial attack, and critters that are up to the task aren’t common.

“Lignin is a highly problematic polymer from the point of view of processing, but an exemplary evolutionary achievement,” researchers at the University of York in England commented in May 2008 in New Phytologist.

To prep for the cell wall attack, plant matter is usually pretreated: the shredded, chopped or pelletized biomass is typically mixed with dilute acids or ammonia. At a biofuels symposium held in May in San Francisco, scientists presented work describing pretreatment with proton beam irradiation, steam explosion and microwave reactors. Ionic liquids — basically liquid salts — are also under investigation.

“Cellulose doesn’t liquefy in minutes to hours — it’s hours to days,” says Jim McMillan of the national lab in Golden. This step is the main bottleneck in cellulosic fuel production, Lynd and several other researchers conclude in a February 2008 commentary in Nature Biotechnology.

Lignin is typically removed after pretreatment and then burned in the refinery’s boiler, replacing some fossil fuel use. The remaining plant matter is then broken into simple sugars, typically by a cocktail of microbial enzymes known as cellulases. Other microbes are then called in to ferment the sugars into ethanol.

Breaking down cellulose with enzymes is usually a separate step from fermentation — and a very costly one. But recent attempts to combine the conversion of cellulose to sugars with the conversion of sugars to fuel — called consolidated bioprocessing — have been successful. A strain of the soil-dwelling bacterium Clostridium phytofermentans will happily munch biomass such as wood pulp waste and will ferment it into ethanol. That discovery, by microbiologist Susan Leschine of the University of Massachusetts Amherst, led to the development of Qteros, a cellulosic-ethanol start-up in Marlborough, Mass. And in May, Mascoma researchers reported the engineering of a yeast and the bacterium Clostridium thermocellum to produce cellulases and ethanol in a single step.

At the San Francisco conference, posters reported on investigations of even more enzymes from various sources: bacteria that live in the deep sea, penicillin, diseased sea squirts, the bread mold Neurospora, a yeast that grows on wood-boring beetles and soil microbes from a Puerto Rican rainforest. Scientists are also fighting recalcitrance from the inside out by breeding lines of low-lignin plants.

Of course, getting a lot of ethanol in a benchtop flask is one thing. Scaling up to a silo-sized bioreactor is another. Industrial models exist — such as wringing pulp from trees for the paper industry or mass-producing cornstarch. “But we haven’t done it with cellulose yet,” says McMillan.

More than a dozen pilot plants for producing cellulosic ethanol are under construction and a handful are operating, with 2011 seen as the year for cellulosic technologies to walk the walk. The group at Idaho National Lab hopes to be able to demonstrate a system from field to refinery by autumn of 2010.

Environmental cost

Yet concerns remain that the environmental side of the biofuels equation is still not worked out. Some argue that the numbers are too fuzzy to proceed with confidence that environmental burdens and benefits have been fully considered.

“There are people who say we don’t have enough knowledge to move forward — to some extent that is true,” says Michigan State University’s Philip Robertson, coauthor of the Science policy paper. “But we do know a lot about sustainability — enough to implement logical science-based standards.” This includes things like the strategic use of cover crops, fertilizer and tilling.

There is also the consideration of land-use changes — if forests are cleared for biofuels production, far more carbon will be released than is saved by the nonpetroleum fuels, several studies suggest. Such findings have led to scrutiny that has stung many in the industry who argue that biofuels are being held to a much higher standard than fossil fuels. If the petroleum isn’t “charged” for the greenhouse gas emissions of the U.S. military keeping supply lanes open in the Persian Gulf, why should emissions from cleared forests be included in the biofuels ledger? asks Bruce Dale of Michigan State University in a recent editorial in the journal Biofuels, Bioproducts & Biorefining.

Congress is now considering legislation that may determine whether indirect land use can or cannot be a mark on the ruler used by the U.S. Environmental Protection Agency to measure biofuels’ impacts. Eventually, many researchers hope, a more detailed picture will emerge of the benefits and costs across all stages of the life cycles of fossil and next-generation fuels.

“Some really interesting services are going to emerge from these crops,” says Muth, of the Idaho National Lab. Some biofuel plants help sequester carbon in the soil, for example. A 2002 analysis reported that by the second or third planting year, switchgrass plots experience far less soil erosion than annual crops such as corn. Species that do well near wetlands can act as filters, preventing nitrates and phosphates from getting into the water, Muth says. “If there is a value on carbon sequestration ... a value on clean water, there may be economic benefits for a lot of these crops.”

Robertson adds, “If certain practices were being promoted with incentives, it would ensure that we have a biofuels industry that is sustainable with a net benefit, not a cost. We don’t have that yet — I say ‘yet’ hopefully.”

With appropriate carrots and sticks, biofuels could play a big role in the energy portfolio of the future. There may even be a day when, Back to the Future style, garbage can be thrown into a personal-sized bioreactor that yields fuel. (Trash biomass in the form of sugar beet pulp, tomato pomace, cashew apple, grape pomace, sweet gum and coffee pulp are all being investigated.) Several lines of research are investigating biofuel “coproducts,” high-value molecules that can be extracted during processing, such as proteins for animal feed or aromatics for perfumes and drugs. These products will also bring the net costs of these fuels down, one of several variables that can help the biofuels math add up to success as a fossil fuel substitute.

“It’s difficult to compare the costs of not changing with the costs of changing,” Lynd said at the May meeting in San Francisco. “Asking is this or that realistic is well-intentioned, but all solutions involve changes — we don’t have an option. Business as usual? Well, we think of it as a baseline, but it is a fantasy — even if you don’t care about carbon — just as a supply issue. Fossil fuels will all be gone. They’ll all be gone.”

A researcher examining a sample of algal oil.Running on algae

Pond scum gets a bad rap. But microalgae — tiny, single-celled aquatic organisms — are rising stars in the renewable energy sector. They can provide oil that can be turned into liquid fuels such as biodiesel and jet fuel.

Algal oil is mostly triacylglycerides — long fatty acid chains with glycerol backbones — that can be converted to diesel and other fuels in relatively few steps. Algae’s potential lies in their speedy growth rate, efficient photosynthesis and flexible habitat preferences. Many strains can grow in saltwater or wastewater from treatment plants. In open ponds or closed bioreactors, the microorganisms can potentially make more than 50 times as much oil as land plants on the same area.

This potential fuel has a long history. In 1978 the Department of Energy launched the Aquatic Species Program to develop fuels from algae, but the program was shut down in 1996. In the intervening years, more than 3,000 strains were investigated, included species from Yellowstone National Park’s hot springs and the Caribbean Sea.

Now algae research is surging once again in both the private and public sectors. Problems still loom, including how to best extract the oil, scale up algae farms and control contamination by unwanted strains or tiny critters like rotifers that graze on the algal crop. But in June the algae-to-ethanol company Algenol Biofuels announced plans for a pilot plant with Dow Chemical Co. in Freeport, Texas. And in January, Continental Airlines conducted a 90-minute test flight of a Boeing 737 fueled in part by a blend derived from algae and Jatropha plants. Prospects for fuel from pond scum are starting to look up.

Black Holes Join Together

2009-07-05T15:23:00.000-07:00

The first solid evidence of a new class of medium-sized black holes has been discovered in a distant galaxy by an international team of astronome

Image via Wikipedia

rs.

Image via Wikipedia

The black hole is more than 500 times the mass of the Sun, the researchers report in the journal Nature.

Until now, identified black holes have been either super-massive (several million to several billion times the mass of the Sun) in the centre of galaxies, or about the size of a typical star (between three and 20 Solar masses).

The team, led by astrophysicists at the Centre d'Etude Spatiale des Rayonnements in France, detected the new black hole approximately 290 million light years from Earth with the European Space Agency's XMM-Newton X-ray space telescope.

A black hole is an object with such a powerful gravitational field that it absorbs all the light that passes near it and reflects nothing.

It had been long believed by astrophysicists that there might be a third, intermediate class of black holes, with masses between a hundred and several hundred thousand times that of the Sun. However, such black holes had not been reliably detected until now.

Image by Ethan Hein via Flickr

"While it is widely accepted that stellar mass black holes are created during the death throes of massive stars, it is still unknown how super-massive black holes are formed," says a member of the team, Dr Sean Farrell, who recently completed his PhD studies at the Campus of the University of New South Wales at the Australian Defence Force Academy and now works at the University of Leicester, UK.

"One theory is that super-massive black holes may be formed by the merger of a number of intermediate mass black holes. To ratify such a theory, however, you must fi

Image by Getty Images via Daylife

rst prove the existence of intermediate black holes.

"The identification of HLX-1 is therefore an important step towards a

Image by Smithsonian Institution via Flickr

better understanding of the formation of the super-massive black holes that exist at the centre of the Milky Way and other galaxies."

This new source, identified as HLX-1 (Hyper-Luminous X-ray source 1), lies towards the edge of the galaxy ESO 243-49. It is ultra-luminous in X-rays, with a maximum X-ray brightness of approximately 260 million times that of the Sun.

The X-ray signature of HLX-1 and the lack of a counterpart in optical images confirm that it is neither a foreground star nor a background galaxy, and its position indicates that it is not the central engine of that galaxy.

Using XMM-Newton observations carried out on the 23rd November 2004 and the 28th November 2008, the team showed that HLX-1 displayed a variation in its X-ray signature. This indicated that it must be a single object and not a group of many fainter sources. The huge radiance observed can only be explained if HLX-1 contains a black hole more than 500 times the mass of the Sun. No other physical explanation can account for the data.

Micro Images of Body Parts

2009-06-29T15:02:00.000-07:00

Get up close and personal with your innards with these 15 amazing 3D-body shots.
Almost all of the following images were captured using a scanning electron microscope (SEM), a type of electron microscope that uses a beam of high-energy electrons to scan surfaces of images.

The electron beam of the SEM interacts with atoms near or at the surface of the sample to be viewed, resulting in a very high-resolution, 3D-image.

Magnification levels range from x 25 (about the same as a hand lens) to about x 250,000.
Incredible details of 1 to 5 nm in size can be detected.

1. Red Blood Cells

They look like little cinnamon candies here, but they're actually the most common type of blood cell in the human body - red blood cells (RBCs). These biconcave-shaped cells have the tall task of carrying oxygen to our entire body; in women there are about 4 to 5 million RBCs per micro liter (cubic millimeter) of blood and about 5 to 6 million in men. People who live at higher altitudes have even more RBCs because of the low oxygen levels in their environment.

2. Split End of Human Hair

Regular trimmings to your hair and good conditioner should help to prevent this unsightly picture of a split end of a human hair.

3. Purkinje Neurons

Of the 100 billion neurons in your brain. Purkinje neurons are some of the largest. Among other things, these cells are the masters of motor coordination in the cerebellar cortex. Toxic exposure such as alcohol and lithium, autoimmune diseases, genetic mutations including autism and neurodegenerative diseases can negatively affect human Purkinje cells.

4. Hair Cell in the Ear

Here's what it looks like to see a close-up of human hair cell stereo cilia inside the ear. These detect mechanical movement in response to sound vibrations.

5. Blood Vessels Emerging from the Optic Nerve

In this image, stained retinal blood vessels are shown to emerge from the black-colored optic disc. The optic disc is a blind spot because no light receptor cells are present in this area of the retina where the optic nerve and retinal blood vessels leave the back of the eye.

6. Tongue with Taste Bud

This colour-enhanced image depicts a taste bud on the tongue. The human tongue has about 10,000 taste buds that are involved with detecting salty, sour, bitter, sweet and savoury taste perceptions.

7. Tooth Plaque

Brush your teeth often because this is what the surface of a tooth with a form of “corn-on-the-cob” plaque looks like.

8. Blood Clot

Remember that picture of the nice, uniform shapes of red blood cells you just looked at? Well, here's what it looks like when those same cells get caught up in the sticky web of a blood clot. The cell in the middle is a white blood cell.

9. Alveoli in the Lung

This is what a colour-enhanced image of the inner surface of your lung looks like. The hollow cavities are alveoli; this is where gas exchange occurs with the blood.

10. Lung Cancer Cells

This image of warped lung cancer cells is in stark contrast to the healthy lung in the previous picture.

11. Villi of Small Intestine

Villi in the small intestine increase the surface area of the gut, which helps in the absorption of food. Look closely and you’ll see some food stuck in one of the crevices.

12. Human Egg with Coronal Cells

This image is of a purple, colour-enhanced human egg sitting on a pin. The egg is coated with the zona pellicuda, a glycoprotein that protects the egg but also helps to trap and bind sperm. Two coronal cells are attached to the zona pellicuda.

13. Sperm on the Surface of a Human Egg

Here's a close-up of a number of sperm trying to fertilize an egg.

14. Human Embryo and Sperm

It looks like the world at war, but it’s actually five days after the fertilisation of an egg, with some remaining sperm cells still sticking around. This fluorescent image was captured using a confocal microscope. The embryo and sperm cell nuclei are stained purple while sperm tails are green. The blue areas are gap junctions, which form connections between the cells.

i

Ferrari Concept Bikes

2009-06-24T22:36:00.000-07:00

Renewable Energy from Ocean

2009-06-07T01:23:00.000-07:00

Power is currently being harvested from the ocean in two different ways:

There are three basic ways to tap the ocean for its energy. We can use the ocean's waves, we can use the ocean's high and low tides, or we can use temperature differences in the water. Let's take a look at each.

Wave Energy

Kinetic energy (movement) exists in the moving waves of the ocean. That energy can be used to power a turbine. In this simple example, to the right, the wave rises into a chamber. The rising water forces the air out of the chamber. The moving air spins a turbine which can turn a generator.

When the wave goes down, air flows through the turbine and back into the chamber through doors that are normally closed.

This is only one type of wave-energy system. Others actually use the up and down motion of the wave to power a piston that moves up and down inside a cylinder. That piston can also turn a generator.

Most wave-energy systems are very small. But, they can be used to power a warning buoy or a small light house.

Tidal Energy

Pictures of La Rance Tidal Station Another form of ocean energy is called tidal energy. When tides comes into the shore, they can be trapped in reservoirs behind dams. Then when the tide drops, the water behind the dam can be let out just like in a regular hydroelectric power plant.

Tidal energy has been used since about the 11th Century, when small dams were built along ocean estuaries and small streams. the tidal water behind these dams was used to turn water wheels to mill grains.

In order for tidal energy to work well, you need large increases in tides. An increase of at least 16 feet between low tide to high tide is needed. There are only a few places where this tide change occurs around the earth. Some power plants are already operating using this idea. One plant in France makes enough energy from tides (240 megawatts) to power 240,000 homes.

This facility is called the La Rance Station in France. It began making electricity in 1966. It produces about one fifth of a regular nuclear or coal-fired power plant. It is more than 10 times the power of the next largest tidal station in the world, the 17 megawatt Canadian Annapolis station.

Ocean Thermal Energy Conversion (OTEC)

The idea is not new. Using the temperature of water to make energy actually dates back to 1881 when a French Engineer by the name of Jacques D'Arsonval first thought of OTEC. The final ocean energy idea uses temperature differences in the ocean. If you ever went swimming in the ocean and dove deep below the surface, you would have noticed that the water gets colder the deeper you go. It's warmer on the surface because sunlight warms the water. But below the surface, the ocean gets very cold. That's why scuba divers wear wet suits when they dive down deep. Their wet suits trapped their body heat to keep them warm.

Power plants can be built that use this difference in temperature to make energy. A difference of at least 38 degrees Fahrenheit is needed between the warmer surface water and the colder deep ocean water.

Advantages of Tidal and Wave Generators

Today’s most promising water-based generators operate something like floating wind turbines anchored to the sea floor. Moving ocean water creates pressure that turns a hydraulic turbine, which in turn is linked to a generator that converts the hydraulic energy into electricity.

Ocean-powered generators have important advantages over both conventional forms of power and other renewable energy alternatives, such as wind and solar power. Ocean-generated energy is:

* Clean. Unlike coal, oil, or nuclear energy, the electricity produced by tidal or wave generators is emission free. Powering houses with ocean-generated electricity could potentially save millions of tons of carbon emissions each year.
* Unobtrusive. Ocean-borne generators ride the waves without protruding above the water’s surface, so they don’t obstruct views the way today’s huge wind turbines can.
* Consistent. Waves and tidal movements are predictable and occur all year round, so ocean generators aren’t affected by clouds or seasonal changes as solar collectors are.

Moving from Experimental Technology to Commercial Reality

Wave and tidal generators are currently in advanced phases of testing or initial commercial operation in several locations around the world. A tidal current generator developed by Sea Generation Ltd. began operating in Northern Ireland’s Strangford Lough in June, 2007, with a potential capacity of 1.2 megawatts. A wave farm consisting of three generators built by Pelamis Wave Power opened off Portugal in September, 2008. Operating at full capacity, the farm can generate enough electricity to power more than 1,500 houses. Both of those projects, though, have been dogged by technical problems caused by the harsh ocean environment.

British company Checkmate Seaenergy developed a new, simpler generator, the Anaconda Wave Energy Converter, to help combat breakdowns caused by the corrosive effects of seawater. While the Seagen and Pelamis turbines are primarily made of metal, the Anaconda is made mainly from fabric and rubber.

A small-scale Anaconda generator has just completed testing in a tank in Hampshire, England. If the tests prove successful, larger versions of the power generator will be tested in the ocean. Checkmate Seaenergy, the Anaconda’s maker, hopes to have wave generators in commercial production by 2014.

Future Prospects for Renewable Energy from the Ocean

Many governments have set ambitious targets for generating electricity from renewable sources. The European Union plans to generate 20% of its electricity from renewables by the year 2020. The United States recently set a target of generating 25% of all electricity renewably by 2025.

As with many new technologies, getting the funding to overcome technical problems and test new installations is one of the major obstacles standing between ocean-power generation and commercial success. Even in a difficult economic climate, the new water-powered generators are promising enough that governments and private companies are pressing ahead with plans to generate a small but significant part of their electricity needs from the ocean.

Generating technologies for deriving electrical power from the ocean include tidal power, wave power, ocean thermal energy conversion, ocean currents, ocean winds and salinity gradients. Of these, the three most well-developed technologies are tidal power, wave power and ocean thermal energy conversion. Tidal power requires large tidal differences which, in the U.S., occur only in Maine and Alaska. Ocean thermal energy conversion is limited to tropical regions, such as Hawaii, and to a portion of the Atlantic coast. Wave energy has a more general application, with potential along the California coast. The western coastline has the highest wave potential in the U.S.; in California, the greatest potential is along the northern coast.

Energy

California has more than 1,200 kilometers (745 miles) of coastline, and the combined average annual deep water wave power flux is over 37,000 megawatts (MW) of which an upper limit of about 20 percent could be converted into electricity. This is sufficient for about 23 percent of California's current electricity consumption. However, economics, environmental impacts, land-use and grid interconnection constraints will likely impose further limits to how much of the resource can be extracted. Although technology is still at a relatively immature pilot project stage, economic projections indicate that ocean energy could become cost-competitive over the long-term.

Current Pilot Projects

In the spring of 2009, the Sonoma County Water District applied to the Federal Energy Regulatory Commission (FERC) for three wave project preliminary permits. The projects will be located in state waters offshore Del Mar Landing (the northwestern portion of the county) and off Fort Ross further to the south. Each of the three projects would begin as pilots in the two to five megawatt (MW) range, could potentially expand to commercial facilities in the 40-200 MW range, and would include substations, transmission lines, appurtenant facilities, and submersible electric cables.

With these applications, the total number of FERC permits and applications for wave and tidal projects in California waters totals twelve.

Wave Energy

Wave energy conversion takes advantage of the ocean waves caused primarily by interaction of winds with the ocean surface. Wave energy is an irregular and oscillating low-frequency energy source that must be converted to a 60-Hertz frequency before it can be added to the electric utility grid.

Although many wave energy devices have been invented, only a small proportion have been tested and evaluated. Furthermore, only a few have been tested at sea, in ocean waves, rather than in artificial wave tanks.

As of the mid-1990s, there were more than 12 generic types of wave energy systems. Some systems extract energy from surface waves. Others extract energy from pressure fluctuations below the water surface or from the full wave. Some systems are fixed in position and let waves pass by them, while others follow the waves and move with them. Some systems concentrate and focus waves, which increases their height and their potential for conversion to electrical energy.

A wave energy converter may be placed in the ocean in various possible situations and locations. It may be floating or submerged completely in the sea offshore or it may be located on the shore or on the sea bed in relatively shallow water. A converter on the sea bed may be completely submerged, it may extend above the sea surface, or it may be a converter system placed on an offshore platform. Apart from wave-powered navigation buoys, however, most of the prototypes have been placed at or near the shore

The visual impact of a wave energy conversion facility depends on the type of device as well as its distance from shore. In general, a floating buoy system or an offshore platform placed many kilometers from land is not likely to have much visual impact (nor will a submerged system). Onshore facilities and offshore platforms in shallow water could, however, change the visual landscape from one of natural scenery to industrial

The incidence of wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites. The cost, however, of electricity transmission from deep ocean sites is prohibitively high. Wave power densities in California's coastal waters are sufficient to produce between seven and 17 megawatts (MW) per mile of coastline

According to the European Union, "Among the different converters capable of exploiting wave power, the most advanced is unquestionably the Pelamis Wave Energy Converter, a kind of "undulating sea serpent" developed by Ocean Power Delivery. This technology is the object of a commercial contract for installation of a farm in Portugal. In 2007, three machines, with a total capacity of 2.25 megawatts (MW(, are in installation phase, and should be joined by 27 others in the years to come. Another 5 MW project is being studied for England this time."
None of these plants are located in California, although economic feasibility studies have been performed for a 30 MW wave converter to be located at Half Moon Bay. Additional smaller projects have been discussed at Fort Bragg, San Francisco and Avila Beach. There are currently no firm plans to deploy any of these projects

As of the mid-1990s, wave energy conversion was not commercially available in the United States. The technology was in the early stages of development and was not expected to be available within the near future due to limited research and lack of federal funding. Research and development efforts are being sponsored by government agencies in Europe and Scandinavia

Many research and development goals remain to be accomplished, including cost reduction, efficiency and reliability improvements, identification of suitable sites in California, interconnection with the utility grid, better understanding of the impacts of the technology on marine life and the shoreline. Also essential is a demonstration of the ability of the equipment to survive the salinity and pressure environments of the ocean as well as weather effects over the life of the facility

Permitting Issues. Some of the issues that may be associated with permitting an ocean wave energy conversion facility include:

* Disturbance or destruction of marine life (including changes in the distribution and types of marine life near the shore)
* Possible threat to navigation from collisions due to the low profile of the wave energy devices above the water, making them undetectable either by direct sighting or by radar. Also possible is the interference of mooring and anchorage lines with commercial and sport-fishing.
* Degradation of scenic ocean front views from wave energy devices located near or on the shore, and from onshore overhead electric transmission lines

Tidal Energy

Another form of ocean energy is called tidal energy. When tides comes into the shore, they can be trapped in reservoirs behind dams. Then when the tide drops, the water behind the dam can be let out just like in a regular hydroelectric power plant.

Tidal energy has been used since about the 11th Century, when small dams were built along ocean estuaries and small streams. the tidal water behind these dams was used to turn water wheels to mill grains.

In order for tidal energy to work well, you need relateivel large increases in tides. An increase of at least 16 feet between low tide to high tide is generally needed. There are only a few places where this tide change occurs around the earth. Some power plants are already operating using this idea.

According to the European Union:

"Ninty percent of today's worldwide ocean energy production is represented by a single site: the La Rance Tidal Power Plant (240 MW) that was commissioned in 1966. This type of installation has remained unique in the world and has only been reproduced at much smaller capacities in Canada (20 MW), China (5 MW) and Russia (0.4 MW).

"This type of project was abandoned for many years because of very high initial investment costs as well as the strong local impact that results from it. However, the present economic situation has encouraged South Korea to build a 260 MW dam closing off Sihwa Lake, which is set to be commissioned in 2009. Lighter new techniques, like hydro turbines, are being developed today to harness ocean currents. The leader in this field, the British company, Marine Current Turbine (MCT), should install 1.2MW in Northern Ireland following its 300 kW pilot project in Bristol Bay."

Ocean Thermal Energy Conversion (OTEC)

The idea of using the temperature of water to make energy actually dates back to 1881 when a French Engineer by the name of Jacques D'Arsonval first thought of OTEC. The final ocean energy idea uses temperature differences in the ocean. If you ever went swimming in the ocean and dove deep below the surface, you would have noticed that the water gets colder the deeper you go. It's warmer on the surface because sunlight warms the water. But below the surface, the ocean gets very cold. That's why scuba divers wear wet suits when they dive down deep. Their wet suits trapped their body heat to keep them warm.

Power plants can be built that use this difference in temperature to make energy. A difference of at least 38 degrees Fahrenheit is needed between the warmer surface water and the colder deep ocean water. The cold ocean water can also be used to cooling buildings, and desalinated water is often a by-product.

Ten 3D || Ten Robots

2009-06-03T16:46:00.000-07:00