SECRET OF PLANETS

The Glossary of Telescopes

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 17:03:00 +0000

When you enter into any new area of science, you almost always find yourself with a baffling new language of technical terms to learn before you can converse with the experts. This is certainly true in astronomy both in terms of terms that refer to the cosmos and terms that describe the tools of the trade, the most prevalent being the telescope. So to get us off of first base, let’s define some of the key terms that pertain to telescopes to help you be able to talk to them more intelligently.

The first area of specialization in telescopes has to do with the types of telescopes people use. The three designs of telescopes that most people use are the Refractor, the Reflector and the Schmidt Cassegrain telescope.

*    The refractor telescope uses a convex lens to focus the light on the eyepiece.

*    The reflector telescope has a concave lens which means it bends in. It uses mirrors to focus the image that you eventually see.

*    The Schmidt Cassegrain telescope uses an involved system of mirrors to capture the image you want to see.

*    A binocular telescope uses a set of telescopes mounted and synchronized so your view of the sky is 3-D.

Beyond the basic types, other terms refer to parts of the telescope or to the science behind how telescopes work.

*    Collimation is a term for how well tuned the telescope is to give you a good clear image of what you are looking at. You want your telescope to have good collimation so you are not getting a false image of the celestial body.

*    Aperture is a fancy word for how big the lens of your telescope is. But it’s an important word because the aperture of the lens is the key to how powerful your telescope is. Magnification has nothing to do with it, its all in the aperture.

*    Focuser is the housing that keeps the eyepiece of the telescope, or what you will look through, in place. The focuser has to be stable and in good repair for you to have an image you can rely on.

*    Mount and Wedge. Both of these terms refer to the tripod your telescope sits on. The mount is the actual tripod and the wedge is the device that lets you attach the telescope to the mount. The mount and the wedge are there to assist you with a superior viewing session and to keep your expensive telescope safe from a fall.

*    An Altazimuth Mount refers to the tripod of the telescope that holds the device in place and makes it useful during a star gazing session. The altazimuth mouth allows the telescope to move both horizontally (which is the azimuth) and vertically. In this way you have full range to look at things close to the horizon or directly overhead.

*    Coma has a different meaning than the one we are used to, and that’s a good thing. The coma is the blurry area on the outer rims of your view through the telescope. How big the coma is and to what extent it interferes with your viewing will have is important to the effectiveness of your telesscope.

*    Planisphere. A fancy word for a star chart. It is nothing less or more than a detailed map of where everything is in the cosmos and how to find the star you wish to study by keying off of known stars.

*    Barlow. This refers to a specialized type of lens that you can buy to enhance the magnification of your telescope.

These are just a few of the basic concepts of telescope operation. We deliberately picked the ones you have to know to discuss telescopes intelligently. But your education into the more complex aspects of astronomy and telescope design and operation will go on for as long as you are a lover of astronomy, which we hope is for the rest of your life.

Space

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 17:02:00 +0000

While it was just a TV show, that little speech at the beginning of the original Star Trek show really did do a good job of capturing our feelings about space. It is those feelings that drive our love of astronomy and our desire to learn more and more about it.

The thing that is most exciting about studying the universe is also the most frustrating and that is that no matter how expert we get, we are always just getting started. But if it’s any consolation, some of the most advanced minds in science and from history always felt that way about space. Even the greats such as Copernicus and Einstein looked up into space and felt like they were just a spec in the presence of such infinity.

Of course space is not infinite. It has to be finite which means somehow there must be an end to it. But if there is, nobody on this tiny planet has figured out where it is. The only thing that has brought us to “the end of the universe” is our limited ability to see any deeper into space.

But conquering the final frontier of space means more than just seeing more stars and planets and building the biggest telescope we can. There are some mind blowing concepts about how space works that we have ahead of us to conquer. The big bang and the expanding universe alone was enough to set your mind to spinning. But then we have the coming of Einstein and the theory of relativity to set the entire idea on its ear. All of a sudden space is not just three dimensions but the dimension of time becomes exportable and the twisting and maybe even travel through time seems almost possible.

The frontier of space is as much a journey of the mind as it is of distance. When Steven Hawking showed us the mysteries of black holes, all of a sudden, time and space could collapse and be twisted and changed in those intergalactic pressure cookers. If not for the wonders of radio astronomy, these ideas would remain just ideas but slowly science is catching up with theory.

But the brilliance of mathematicians and genius minds like Hawking and Einstein continue to stretch our concepts of space. Now we have the string theory that could revolutionize everything we know about space, time and how the universe relates to itself. We can’t just say, no, we have discovered enough. It’s the final frontier. The Starship Enterprise would not stop exploring so neither can we. Because there is a hurdle still ahead that has a name but no real answer to it yet. It’s called the Unified Field Theory and those that know tell us that when the Einsteins and Hawkings of our day crack that theory, every other theory will fall into place.

These exciting concepts seem some tools to put the enormity of space in context. That may also be the value of science fiction. Not only are science fiction writers often the visionaries of what comes to be in the future but they give us the idea that space is knowable, that despite how big it is and how small we are, we can conquer this frontier like we have conquered others before us.

For mankind, that is often enough. If we can get the vision that we can conquer something, even if it is something so massive, so impossibly huge, it seems that we are capable of anything. And the love of astronomy, maybe unlike any other force on earth, has brought together mankind toward that common goal of conquering the universe. The quest to establish an international space station and to cooperate on spreading our reach off of this planet seems to find commonality between nations that otherwise cannot get along on the surface of the earth.

That alone may be a reason that we must continue to support astronomy locally and the space program nationally. It is something that seems to bring peace rather than war and make us a better people. But more than that it is as though this is what we were created to do. To reach out to the stars may be our destiny. If so then our love of astronomy is more than a hobby, it’s a calling.

Pictures in the Sky

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 17:01:00 +0000

One of the earliest activities we engaged in when we first got into astronomy is the same one we like to show our children just as soon as their excitement about the night sky begins to surface. That is the fun of finding constellations. But finding constellations and using them to navigate the sky is a discipline that goes back virtually to the dawn of man. In fact, we have cave pictures to show that the more primitive of human societies could “see pictures” in the sky and ascribe to them significance.

Constellations also have been important in culture and navigation long before we had sophisticated systems of navigation. Early explorers, particularly by sea, relied exclusively on the night sky to help them find their way to their destination. In fact, when “Columbus sailed the ocean blue in 1492” and “discovered” America, he could not have done it without astronomy and the help of navigation of the cosmos, much of which is made possible because of the important constellations.

When learning to find the great constellations in the sky, we use the “find one, you found them all” system. That is because the easiest constellation to find will guide us to the rest of them. That constellation is The Big Dipper. Look to the northern sky on a clear night and widen your field of vision from just focusing on one star and it will pretty much jump out at you. In will look like a big kitchen pot or ladle, right side up in the fall, upside down in the spring.

When you have the big dipper under control, you can pretty easily find the North Star. This is the star that those ancient sailors depended on the most to find their way to land. Start with the far edge of the bowl of the Big Dipper, the side that is opposite the handle. There are two stars that make up that side of the bowl. So start at the bottom of the pot and mentally draw a line to the top star of the bowl. These two stars are “pointing” to the North Star. Just keep following that line, curving a bit with the sky and the bright star that you come to is the North Star. You can impress your friends or family if you know the scientific name for this star is Polaris.

The North Star can then take you to The Little Dipper. The key here is that Polaris is the tip of the handle of The Little Dipper and the bowl hangs down from the handle like it was hanging up in the kitchen. Be patient with this one as the stars that make up The Little Dipper are dimmer than The Big Dipper. But it pretty cool once you find it.

These are the obvious starting places but from The Little Dipper you can find the constellation known as “The Swan” or Cygnus. Just use the same system you used to find The North Star but continue drawing that line that started in those pointer stars in the bowl of The Big Dipper. Go about half as far as you went to find Polaris and you are there. You will see a trapezoid of stars about as big as The Big Dipper. This trapezoid forms the tail of The Swan.

That line that we are drawing from the pointer stars is our roadmap to another well known constellation which is Cassiopeia. If you use that line and imagine you are directly under the two pointer stars, you will se a big “W” just off to the left of the line. This is the constellation Cassiopeia, the wife of the king of Egypt, Cepheus, in Greek mythology. There are so many more wonderful constellations to find and a good star map can continue your quest.

Like Cassiopeia, all of the constellations have wonderful stories and myths related to Greek culture. It is just as fun to find the star clusters themselves as it is to enjoy the rich culture related to that constellation. For all of the signs of the zodiac, for example, there is a related constellation in the sky. So whether you are serious about astrology or not, its fun to find the constellation that relates to your “sign” (or that of your children) and be able to see how the ancients related to these pictures in the sky.

Moon Fever

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 17:00:00 +0000

Of all of the celestial bodies that capture our attention and fascination as astronomers, none has a greater influence on life on planet Earth than it’s own satellite, the moon. When you think about it, we regard the moon with such powerful significance that unlike the moons of other planets which we give names, we only refer to our one and only orbiting orb as THE moon. It is not a moon. To us, it is the one and only moon.

The moon works its way into our way of thinking, our feelings about romance, our poetry and literature and even how we feel about our day in day out lives in many cases. It is not only primitive societies that ascribe mood swings, changes in social conduct and changes in weather to the moon. Even today, a full moon can have a powerful effect on these forces which we acknowledge even if we cannot explain them scientifically.

The most obvious physical phenomenon that is directly affected by the gravity of the moon are the tides of the ocean. The tides are an integral part of how maritime life is regulated and the comings and goings of the fishing world in coastal communities. But not very many people know that at certain times of the year when the orbits of the earth bring the sun and moon into right alignment, there can even be tidal effect on inland bodies of water and even on the solid earth. Eons ago, when the moon’s orbit was closer to the Earth, it was the effect of the moon that caused massive changes in the topography of the land and on continental drift as well. This reflects the powerful effect the moon has had on both human history and on global geographical history as well.

You may sometimes wonder where the moon came from. Was it a planet that traveled too close to Earth and was captured in our orbit? Actually, the prevailing theory of modern science is that the moon was the result of a large scale collision with the still developing Earth early in its development which caused this large “chuck” to spin off into an orbiting body. This explains the similarity in composition as has been confirmed by many of the moon exploratory space missions that were conducted by NASA.

But this background also highlights another important influence the moon has had on Earth’s development that is seldom recognized and that is the stabilization of Earth’s orbital pattern. Most know that Earth is not round but more of an egg shaped orb. To be blunt, the Earth would wobble. Without the moon’s stabilizing influence, this shape would shift dramatically so the tilt of the axis, that is the polar caps would shift dramatically with each seasonal rotation producing climacteric, changes much more violent and drastic than we are used to. It is possible that life as we know it could not have developed here had the moon not been there to “keep the Earth in line” and continue to stabilize the orbital position of the Earth so our climate could remain stable and mild.

A third significant influence of the moon comes from that origin as coming from a collision which “ripped” the body of the moon from the developing core of the Earth. Because of this disruption in how the core of our planet developed, the metals that are usually intact in the core of the planet are actually scattered up and down the geography of the earth in diverse ways. Usually the metals of the planet are all concentrated deep in the core. But because of the collision which took the moon out to orbit, metals that have been crucial to the development of our industrial and technological cultures are readily available and easy for use to mine. This again, is something we can thank the presence of that lovely moon in the sky for.

Comets

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 16:59:00 +0000

The one thing we love the most in the world of astronomy is a good mystery. And if there was ever a mysterious and yet very powerful force of nature that we witness in the night skies, it is the coming of the mighty comet.

The arrival of a comet within view of Earth is an event of international importance. Witness the huge media attention that the Haley or Hale-Bopp have had when they have come within view The sight of these amazing space objects is simultaneously frightening and awe inspiring.

Above all, it is during these comet viewings that the astronomer comes out in all of us. But what is a comet? Where did it come from? And how does it get that magnificent tail?

We should never confuse comets with asteroids. Asteroids are small space rocks that come from an asteroid belt between Mars and Jupiter. While still quite stunning to see, they pale in comparison to the arrival of a comet. Asteroids also have received considerable study by the scientific community.

Not as much is known about comets. As a rule, comets are considerably larger than asteroids. The composition of a comet is a mixture of nebulous, gasses, ice, dust and space debris. One scientist called the composition of a comet as similar to a “dirty snowball” because the composition is so diverse and changeable. The center or nucleus of a comet is usually quiet solid but the “snowball” materials often create a “cloud” around that nucleus that can become quite large and that extends at great lengths behind the comet as it moves through space. That trailing plume is what makes up the comet’s magnificent tail that makes it so exciting to watch when a comet comes within view of Earth.

The origins of comets is similarly mysterious. There are a number of theories about where they come from but it is clear that they originate from outside our solar system, somewhere in deep space. Some have speculated they are fragments left over from the organization of planets that get loose from whatever gravitational pull and are sent flying across space to eventually get caught up in the gravity of our sun bringing them into our solar system.

Another theory is that they come from a gaseous cloud called the Oort cloud which is cooling out there after the organization of the sun. As this space debris cools, it gets organized into one body which then gathers sufficient mass to be attracted into the gravity of our solar system turning into a fast moving comet plummeting toward our sun. However, because of the strong gravitational orbits of the many planets in our solar system, the comet does not always immediately collide with the sun and often takes on an orbit of its own.

The life expectancy of comets varies widely. Scientists refer to a comet that is expected to burn out or impact the sun within two hundred years as a short period comet whereas a long period comet has a life expectancy of over two hundred years. That may seem long to us as earth dwellers but in terms of stars and planets, this is a very short life as a space object indeed.

Scientists across the globe have put together some pretty impressive probes to learn more about comets to aid our understanding of these visitors from beyond. In 1985, for example, the United States put a probe into the path of the comet Giacobini-Zinner which passed through the comets tail gathering tremendous scientific knowledge about comets. Then in 1986, an international collation of scientists were able to launch a probe that was able to fly close to Haley’s comet as it passed near Earth and continue the research.

While science fiction writers and tabloid newspapers like to alarm us with the possibility of a comet impacting the earth, scientists who understand the orbits of comets and what changes their paths tell us this is unlikely. That is good because some comets reach sizes that are as big as a planet so that impact would be devastating. For now, we can enjoy the fun of seeing comets make their rare visits to our night sky and marvel at the spectacular shows that these visitors from beyond put on when they are visible in the cosmos.

Bonding with the Universe.

noreply@blogger.com (Imran Malik) — Mon, 06 Jun 2011 16:58:00 +0000

As parents, we often worry about what our children are getting excited about. We hope we can guide them to “bond” with healthy things like a love of learning, of family and of healthy social activities. But we also worry they will bond with the wrong people like internet stalkers or the wrong crowd at school. Wouldn’t it be great if we could harness that tremendous energy and desire to latch onto something and bond with it and help our children “bond” with the universe through a love of astronomy?

Kids love to get excited about what you are excited about. So there lots of ways you can “spring” the fun of astronomy on them that will jump start them on a long and happy exploration of the hobby of astronomy. Here are a few to get your imagination going.

*    Work it into an evening in the backyard. If you know the night sky will be particularly exciting the night of a big family barbecue, plan to have some blankets out there. Then as everybody else is playing Frisbee, just lay out a blanket, lay flat on your back and start staring up into the sky with a binoculars. Like the old prank of staring at a far away spot to get people’s interest, your kids will see what you are doing and what to know what is going on. As you let them take a peek, their curiosity will take off like a wild fire and they are hooked.

*    A surprise visit to the country. Sometimes it is hard to see the vast display of stars from within the city. So if you announce that you are going to show them a surprise one night and have them pile into the car, their curiosity will be going wild as you leave the city. When you find that quiet park, field or lake side spot, all you have to do is point up and say “just look” and the magnificence of the night sky will do the rest.

*    A special Christmas gift. You can buy your children an affordable and durable beginner’s telescope along with some easy star maps written just for kids. Imagine when they open this exciting gift and want to know how to use it. Don’t be surprised if you are setting up the new telescope in the snow to show them the great things they will see in the cosmos with the gift that Santa wanted them to have. The gift of astronomy.

*    Unleash the power of a meteor shower on them. You can keep your eye on the events that are predicted for the sky watchers in your area. When the next big meteor shower is about to explode over your area, watch the weather for a clear night and get your kids excited about what they are about to see. As the lights begin to go off over head and you create fun and interesting narration to this dramatic display, the children will be addicts for life for the great experiences that can be had as students of astronomy.

*    Plan a surprise event in with something you are already doing. For example, on vacation, you can plan your route on a cross country trip to bring you within visiting distance of one of the great multimillion dollar telescopes in this country. By contacting them ahead of time, you can be sure they are conducting a tour that coincides with your visit. Just imagine if they can look up at a telescope that is bigger than their house and maybe look through the eyepiece as some amazing cosmic sight, it will be the hit of the vacation.

Astronomy is a great activity to introduce on a family camping trip. As the family sits around the fire after a fun night of camping, all you have to do is just look up and go “Wow, look at that!” When those little heads look up, they will look back down changed children, children in love with the stars.

Astronomy is a healthy passion for your kids and one they can grow with their entire lives. And there is probably no better gift you can give them than the love of the stars, of science and of nature that is all wrapped up together when your kids bond with the universe through astronomy.

>Beyond the Naked Eye

noreply@blogger.com (Imran Malik) — Wed, 13 Apr 2011 08:06:00 +0000

>It’s hard to say when in our lives each of us become aware of this thing called “astronomy”. But it is safe to say that at some point on our lives, each and every one of us has that moment when we are suddenly stunned when we come face to face with the enormity of the universe that we see in the night sky. For many of us who are city dwellers, we don’t really notice that sky up there on a routine basis. The lights of the city do a good job of disguising the amazing display that is above all of our heads all of the time.

So it might be that once a year vacation to a camping spot or a trip to a relative’s house out in the country that we find ourselves outside when the spender of the night sky suddenly decides to put on it’s spectacular show. If you have had that kind of moment when you were literally struck breathless by the spender the night sky can show to us, you can probably remember that exact moment when you could say little else but “wow” at what you saw.

That “Wow” moment is what astrology is all about. For some, that wow moment becomes a passion that leads to a career studying the stars. For a lucky few, that wow moment because an all consuming obsession that leads to them traveling to the stars in the space shuttle or on one of our early space missions. But for most of us astrology may become a pastime or a regular hobby. But we carry that wow moment with us for the rest of our lives and begin looking for ways to look deeper and learn more about the spectacular universe we see in the millions of stars above us each night.

To get started in learning how to observe the stars much better, there are some basic things we might need to look deeper, beyond just what we can see with the naked eye and begin to study the stars as well as enjoy them. The first thing you need isn’t equipment at all but literature. A good star map will show you the major constellations, the location of the key stars we use to navigate the sky and the planets that will appear larger than stars. And if you add to that map some well done introductory materials into the hobby of astronomy, you are well on your way.

The next thing we naturally want to get is a good telescope. You may have seen a hobbyist who is well along in their study setting up those really cool looking telescopes on a hill somewhere. That excites the amateur astronomer in you because that must be the logical next step in the growth of your hobby. But how to buy a good telescope can be downright confusing and intimidating.

Before you go to that big expense, it might be a better next step from the naked eye to invest in a good set of binoculars. There are even binoculars that are suited for star gazing that will do just as good a job at giving you that extra vision you want to see just a little better the wonders of the universe. A well designed set of binoculars also gives you much more mobility and ability to keep your “enhanced vision” at your fingertips when that amazing view just presents itself to you.

None of this precludes you from moving forward with your plans to put together an awesome telescope system. Just be sure you get quality advice and training on how to configure your telescope to meet your needs. Using these guidelines, you will enjoy hours of enjoyment stargazing at the phenomenal sights in the night sky that are beyond the naked eye.

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>Astronomy or Astrology?

noreply@blogger.com (Imran Malik) — Sat, 09 Apr 2011 11:50:00 +0000

>Have you ever finally just gave in to the temptation and read your horoscope in the newspaper on Sunday morning? Sure, we all have. For most of us, it’s a curiosity, an amusement to see what they say our day will be like based on the sign of the zodiac that we were born under. Sometimes we forget that this little diversion is actually part of an ancient science called astrology that has had a powerful effect on many cultures dating back to centuries before Christ.

That is not to say that astrology is a dead art today. It is easy to find astrology advocates in every town, advertising in the newspaper and on television trying to convince us that they can tell our fortune, our future and help cure our ills by exploring the mysteries of astrology.

When you are a lover of astronomy, the confusion between astronomy and astrology by those who don’t really understand the differences can get pretty aggravating. And in early civilizations, the two disciplines were not separate. Astrology was just the religious side of the science of astronomy. So what changed?

The most significant shift that set in motion the separation of the two lines of thought began in the first century when Ptolemy wrote the very first book on astronomy called the Tetrabiblos. In it, he began to suggest that astronomy should be considered a separate science from astrology. It was quite a revolutionary book because it also was the first scientific document to suggest that the earth was not the center of the universe and that astronomy should be focused strictly on the observation and recording of events in the cosmos.

Over the next 2000 years, we have come a long way. Not only has science and religion completely gone their separate ways since Ptolemy but the science of astronomy makes tremendous strides every year that are so phenomenal, Ptolemy would be truly astounded.

Probably the biggest point of diversion between a student of astrology and astronomy is the belief that the position of the stars has meaning over the events on our lives. Of course, we do know that the weather and tides and other important aspects of our lives are affected by the stars, planets and heavenly bodies, particularly the moon. But these things are happening because of completely explainable scientific laws in motion, not because of mystical forces at work.

What can we, as devotees of astronomy conclude about the close relationship between astrology and astronomy? Well, for sure we want to be able to explain to anyone who is confused by the similarity in the words what the differences are. We do not want to see the two approaches to the stars and planets to become confused again. But we should do all we can do keep that distinction clear without becoming skeptical or demeaning towards those who may still hold to the teachings of astrology.

It is important to remember that what is part of a person’s religious life has a level of sacred belief to the one holding it. And it is not respectful to scoff at such things. If for no other reason than out of respect for the ancient origins of astronomy, we should give courtesy who still are exploring whether astrology has any validity for them.

If we can treat each discipline with respect but maintain the separation that must exist between astrology and astronomy, there is no reason both approaches to our admiration of the galaxies cannot coexist in peace and harmony. And for our purposes as astronomers, that harmony will allow us plenty of freedom to enjoy our quest for knowledge for many more centuries to come. And who knows, you might still like to read the horoscope on Sunday morning every so often.

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>Astronomy Binoculars – A Great Alternative

noreply@blogger.com (Imran Malik) — Sat, 09 Apr 2011 11:49:00 +0000

>It seems from the moment you begin to take your love of astronomy seriously, the thing that is on your mind is what kind of telescope will you get. And there is no question, investing in a good telescope can really enhance your enjoyment of your new passion in astronomy. But don’t be too hasty to keep up with the big wigs in the astronomy clubs that have advanced telescopes. There is another alternative that can give you most of the advantages of a telescope and some extra flexibility and reduced cost to boot.

That alternative is a good pair of astronomy binoculars. Mostly we think of binoculars as the thing you use to see the football game when you have to sit in the cheap seats. But if you do some homework and had a good grasp on what your stargazing objectives are, the advantages of astronomy binoculars over an entry level telescope can be pretty convincing.

*    As a rule, they are cheaper. So you can get a lot of good stargazing at much less of an investment. You can always spend more money later but for now, this may be just the solution for you.

*    There are not so many accessories. To own and operate a telescope takes a lot of orientation to how to set up and use the device. Beyond that, tuning it for optimum view and diagnosing it when you have problems can sometimes make the telescope more of the passion than stargazing itself.

*    It is much easier to use. If you have not bought a telescope yet, you may have seen telescope owners going through a laborious set up and break down discipline for each use. This is time they are not looking at the stars. The binocular users are happily stargazing as this goes on.

*    Binoculars are lightweight and portable. Unless you have the luxury to set up and operate an observatory from your deck, you are probably going to travel to perform your viewings. Binoculars go with you much easier and they are more lightweight to carry to the country and use while you are there than a cumbersome telescope set up kit.

So give the binocular option some consideration. To make the most effective choice, however, here are a few facts about astronomy binoculars that will help you evaluate which ones are best for you…

Binoculars have two lens sets, one at the end of the eyepiece and a set right next to your eyes. The ones closest to the eye are called the ocular lenses which magnify the image (make it bigger). The ones closest to the sky are called the objective lenses and the size of these lenses will determine how much sky you can see at once. So anytime you are evaluating binoculars, there are two numbers associated with the set. So if the binoculars have a rating of 15-40, that means that the ocular lenses magnify 15 times and the later number is a relative number to how much of the sky you can see. The higher the second number, the more you can see. The explanation is simple. The bigger the lens, the more light it lets in. But be aware that the bigger the second number, the larger, heavier and more cumbersome the binoculars will be.

You will have to balance these two numbers with both your budget and what you want the binoculars to do for you. If you decide to go with a lower power binoculars, you could become frustrated with what you can see and you may have to take your eyes away from the view to get your orientation and consult the star map more often because your range of vision is so limited.

There will also be a temptation to buy a set of binoculars that have zoom functions and other features that will allow you to use it for other purposes such as hunting, whale watching or seeing the football game from the cheap seats. While this is good economy, those functions will get in the way when you are using the binoculars for astronomy. So if you are considering this purchase as your alternative to buying a telescope, our advice is buy binoculars made just for astronomy and don’t take them to the ball game.

♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥
COOL PHOTOS BANK
WORLD'S BEST DREAMY PHOTOS
NATURE OF GOD
WORLD'S BEST WILDLIFE PHOTOS
Amazing Filter
VINTAGE DESI
MYSTERY OF LIFE
FOR UR COMPUTER
VIRGINE DESI
ART OF LIFE
FASHION OF LIFE
DREAMY HEALTH
FEATURE TECHNOLOGY
PHOTOS WAR
SECRET OF EARN MONEY ONLINE

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>Asteroids

noreply@blogger.com (Imran Malik) — Sat, 09 Apr 2011 11:48:00 +0000

>There is a lot of exciting stuff going on in the stars above us that make astronomy so much fun. The truth is the universe is a constantly changing, moving, some would say “living” thing because you just never know what you are going to see on any given night of stargazing.

But of the many celestial phenomenons, there is probably none as exciting as that time you see your first asteroid on the move in the heavens. To call asteroids the “rock stars” of astronomy is simultaneously a bad joke but an accurate depiction of how astronomy fans view them. Unlike suns, planets and moons, asteroids are on the move, ever changing and, if they appear in the night sky, exciting and dynamic.

Like rock stars, asteroids have been given their fair share of urban myth and lore. Many have attributed the extinction of the dinosaurs to the impact of a huge asteroid on the earth. This theory has some credibility and, if it is true, it evokes some pretty startling images and foreboding fears in the current reining species on earth, the human race.

The fact that asteroids are fast moving space debris only makes their movement and activity more interesting and exciting. Unlike a moon, planet or star, the odds that an asteroid could hit the earth are entirely reasonable and in fact, there are many documented cases of small asteroids making it through our atmosphere and leaving some pretty impressive craters in the earth’s surface.

Popular culture has happily embraced the idea of an asteroid impact. The idea has spawned many a science fiction story adding the idea that alien life forms may ride asteroids to our world and start a “war of the worlds” situation. But by far, the most talked about concept that has captured the imagination and the fears of science fiction fans and the general public is of another asteroid hitting the earth that could wipe out life as allegedly happened to the dinosaurs. In fact, the movie “Armageddon” was based on this idea and the concept that somehow mankind could avert that catastrophe with technology.

But probably the best way to calm our fears and replace science fiction with science is with understanding and knowledge. The truth is, there has been a lot of study of asteroid activity and the serious scientific community has gained significant knowledge of these amazing celestial bodies. A number of probes to asteroids have been conducted which have given us a wealth of information about their composition and how we might predict their behavior.

We now know that the majority of asteroids we get to witness come from an asteroid belt that exists between Mars and Jupiter. It is from this community of asteroids that many of the notable asteroids emerged. Scientists have gained significant knowledge about the composition of asteroids and separated them into classes including class S which comes of the part of the belt that is closest to Mars, classes C, D and V which are classified by composition and a class called “Centaurs” whose flight patterns take them closer to Jupiter and Uranus.

Some of the probes NASA has conducted on near flying asteroids have performed some pretty amazing studies of these eccentric celestial bodies. In 1994 the Galileo probe got within 1000 miles of the asteroid Ida and discovered that Ida actually had its own moon.

Other probes have fired impactors into asteroids and even landed on an asteroid to produce some amazing scientific data for us. There is much to learn about asteroids in our love of astronomy and that knowledge only makes our enjoyment of seeing them in the cosmos even more exciting.

♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥♥
COOL PHOTOS BANK
WORLD'S BEST DREAMY PHOTOS
NATURE OF GOD
WORLD'S BEST WILDLIFE PHOTOS
Amazing Filter
VINTAGE DESI
MYSTERY OF LIFE
FOR UR COMPUTER
VIRGINE DESI
ART OF LIFE
FASHION OF LIFE
DREAMY HEALTH
FEATURE TECHNOLOGY
PHOTOS WAR
SECRET OF EARN MONEY ONLINE

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Strange Planets !

noreply@blogger.com (Imran Malik) — Sun, 05 Dec 2010 08:54:00 +0000

Strange Planets !

Other Earth like planets in the neighboring solar systems ,
which are supposed to have life,

Among the more than 400 planets found beyond our solar system, there are volcanic Super Earths, gas giants that dwarf Jupiter, and worlds with multiple sunsets.
Here are 20 of the most incredible, starting with the very first alien world - 51 Pegasi b was the first planet
discovered in orbit around a normal star other than our Sun. It was found in 1995.

The largest exoplanet ever discovered is also one of the strangest and theoretically should not even exist, scientists say. Dubbed TrES-4, the planet is
about 1.7 times the size of Jupiter and belongs to a small subclass of so-called puffy planets that have extremely low densities. The planet is located
about 1,400 light years away from Earth and zips around its parent star in only three and a half days.

Epsilon Eridani b orbits an orange Sun-like star only 10.5 light years away from Earth. It is so close to us telescopes might soon be able to photograph it.
It orbits too far away from its star to support liquid water or life as we know it, but scientists predict there are other stars in the system that might be good candidates for alien life.

This planet, CoRoT-7b, was the first confirmed rocky world outside our solar system, but it doesn't look like a particularly pleasant place to live. It is tidally
locked to its parent star, and sees hellish 4,000 degrees Fahrenheit (2,200 degrees Celsius). It may also rain rocks and be the core of a vaporized gas giant.

Luke Skywalker's home planet of Tatooine in Star Wars had two suns, but that's paltry compared to a Jupiter-like planet 149 light-years from Earth.
This planet has three suns, with the main star similar in mass to our own sun. The triple-star system is known as HD 188753.
Like Tatooine, the planet there is likely pretty hot. It orbits very close to the main star, completing one orbit every 3.5 days.

The youngest exoplanet yet discovered is less than 1 million years old and orbits Coku Tau 4, a star 420 light-years away. Astronomers inferred
the planet's presence from an enormous hole in the dusty disk that girdles the star. The hole is 10 times the size of Earth's orbit around the
Sun and probably caused by the planet clearing a space in the dust as it orbits the star.

The oldest known planet is a primeval world 12.7 billion years old that formed more than 8 billion years before Earth and only 2 billion years after the Big Bang.
The discovery suggested planets are very common in the universe and raised the prospect that life began far sooner than most scientists ever imagined

Astronomers are finding many worlds now in a category of worlds called Super-Earths, which are between 2 and 10 times the mass of our own Earth.
A world called HD156668b is the second smallest after Gliese 581 e. Some scientists think such worlds could be more susceptible to forming the
conditions for life because their cores are hot and are conducive to volcanism and plate tectonics.

A planet called WASP-12b is the hottest planet ever discovered (about 4,000 degrees Fahrenheit,
or 2,200 degrees Celsius), and orbits its star closer than any other known world. It orbits its star once every
Earth day at a distance of about 2 million miles (3.4 million km). WASP-12b is a gaseous planet, about 1.5 times the mass of Jupiter,
and almost twice the size. It is 870 light-years from Earth.

With a surface temperature of -364 degrees Fahrenheit (-220 degrees Celsius), the extrasolar planet known as OGLE-2005-BLG-390L b is likely
the coldest alien world. It is about 5.5 times as massive as Earth and thought to be rocky.
It orbits a red dwarf star about 28,000 light-years away, making it the most distant exoplanet currently known.

When astronomers observed WASP-18b, they may have seen it in the cosmic moment before its death.
This planet whips around its star in less than one Earth day. Scientists think that this speed coupled with the planet's heft yields strong
gravitational tugs that can alter the planets orbit. If the planet orbits faster than its star spins, it should gradually be moving inward towards its sun, and its doom. Credit: C. CARREAU/ESA/Nature

Astronomers have been able to detect the atmospheres around several exoplanets, including HD 189733b, one of the first alien words to have
its atmosphere sniffed to determine its composition. Glowing methane, which can be produced naturally or possibly signal a biological byproduct,
has been detected on the planet. Credit: ESA, NASA and G. Tinetti

The extrasolar planet GJ 1214b is a rocky planet rich in water that sits about 40 light-years away. It orbits a red dwarf star.
It is the only known Super-Earth exoplanet — worlds that have masses between Earth and Neptune — with a confirmed atmosphere. The planet is about
three times the size of Earth and about 6.5 times as massive. Researchers think it is likely a water world with a solid center. Credit: David A. Aguilar, CfA

SWEEPS-10 orbits its parent star from a distance of only 740,000 miles, so close that one year on the planet happens every 10 hours.
The exoplanet belongs to a new class of zippy exoplanets called ultra-short period planets, which have orbits of less than a day.

Most planets orbit in a plane that corresponds to their parent star's equator. But XO-3b orbits with a crazy tilt of 37 degrees from its star's equator.
The only other known example of such an oddly angled orbit was Pluto, until its demotion to dwarf planet status. There is, however, a planet known to
orbit backwards around its parent star. Credit: NASA. ESA, amd G. Bacon (STScI)

While Neptune has a diameter 3.8 times that of Earth and a mass 17 times Earth's, this Super-Neptune world (named HAT-P-11b) is
4.7 times the size of Earth and has 25 Earth masses. The newfound world orbits very close to its star, revolving once every 4.88 days. As a result,
it is baked to a temperature of around 1100 degrees F. The star itself is about three-fourths the size of our Sun and somewhat cooler.

A planet lighter than a ball of cork is one of the puffiest alien planets known to date. Called HAT-P-1, the planet is about half as
massive as Jupiter but about 1.76 times wider-or 24 percent larger than predicted by theory. It could float in water, if there was a tub large enough to hold it.

One of the several planets within the Gliese 581 star system, called Gliese 581 d, may be one of the most habitable alien worlds known.
Its orbit is at just the right distance for water to potentially exist on the surface. Water is a key ingredient for life as we know it. Gliese 581 is a red dwarf star
20.5 light-years from Earth. It is about 8 times the mass of Earth, and located in an orbit just right for liquid water

One of the densest exoplanets to date is a world known as COROT-exo-3b. It is about the size of Jupiter, but 20 times that planet's mass, making it about
twice as dense as lead. Scientists have not ruled out that the COROT-exo-3b may be a brown dwarf, or failed star.

Blue moon eclipse on new year's eve

noreply@blogger.com (Imran Malik) — Sat, 16 Jan 2010 11:40:00 +0000

Blue moon eclipse on new year's eve



Blue moon eclipse on new year's eve

In 1982, a second full Moon of the month was visible. Known as a ‘‘Blue Moon,’’ the name does not refer to the Moon’s color but reflects the rarity of the event and gives rise to the expression, ‘‘once in a blue moon.’’ The Blue Moon of 1982 was even more special because a total lunar eclipse also occurred (for the United States) then. The image you see below has a strange significance as well. Not only is it the absolute finest photo of the full Moon I have ever seen, but it was recorded at a year's end, too… on December 22, 1999 by incomparable astrophotographer Rob Gendler. That particular December's Moon was special for another reason, as the full phase occurred on the day of the winter solstice, within hours of lunar perigee and just one month away from a lunar eclipse.

Although there were 41 Blue Moons in the twentieth century, there was one of only four during an eclipse, and the only total eclipse of a Blue Moon in the twentieth century. A Blue Moon happens every 2.7 years because of a disparity between our calendar and the lunar cycle. The lunar cycle is the time it takes for the Moon to revolve around Earth: 29 days, 12 hours, and 44 minutes.


So stay tuned. . . It’s about to happen again.

December’s Full Moon is traditionally known as the Old Moon, or the Moon after Yule. And on New Year's Even we’re going to call it Blue. No matter what it is referred to, it is still a lovely sight to watch it rise in its grey-scale glory and glide across the luminous night sky. But for some lucky viewers in much of Europe, Africa, Asia, and Australia the Old Blue Moon after Yule will also partially eclipse!

Only a very small portion of the Moon's southern limb will be in the Earth's umbral shadow, but there will be a noticeable darkening visible over the Moon's face at the point of greatest eclipse. Need more? Then know this eclipse is the one of four lunar eclipses in a short-lived series. The lunar year series repeats after 12 lunations or 354 days. Afterwards it will begin shifting back about 10 days in sequential years. Because of the date change, the Earth's shadow will be about 11 degrees west in sequential events.



For the eclipse, the duration of the partial phase will last within two seconds of a hour long, while the penumbral duration from beginning to end will run about four hours and eleven minutes. Penumbral contact will begin at 17:17:08 UT and umbral contact at 18:52:43 UT. The moment of greatest depth of shadow will occur at 19:22:39 UT, 31 December 2009. It will be visible from all of Africa, Europe, Asia, and Australia

Scientists See Supernova in Action

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 20:38:00 +0000

Scientists See Supernova in Action

Supernova 2007uy in the galaxy NGC2770 was already several weeks old on January 7, 2008 when NASA's Swift satellite took the image at left.
The image on the right was taken two days later and shows Supernova 2008D as well.

Astronomers witnessing the birth of an exploding star for the first time have seen a burst of X-rays as the star disintegrates.
Image: Supernova SN2008D.

A star trembled on the brink of eternity.
Outwardly all was serene, but its inside was falling into chaos.

Far away on the day of Jan. 9, Earth time, a satellite telescope by the name of Swift, which happened to be gazing at the star”s galaxy, a smudge of stars 88 million light-years away in the constellation Lynx, recorded an unexpected burst of invisible X-rays 100 billion times as bright as the Sun.

Alicia Soderberg, a Princeton astronomer who had been using the NASA satellite to study the fading remains of a previous supernova explosion, received the startling results of that observation by e-mail while giving a talk in Michigan.
Recognizing that this was something extraordinary, she sounded a worldwide alert.

In the following hours and days, as most of the big telescopes on Earth, and the Hubble Space Telescope and the Chandra X-ray Observatory watched from space, the star erupted into cataclysmic explosion known as a supernova, lighting up its galaxy and delighting astronomers who had never been able to catch an exploding star before it exploded.

“We caught the whole thing on tape, so to speak,” Dr. Soderberg said in an interview.
“I truly won the astronomy lottery. A star in the galaxy exploded right in front of my eyes.”

She and 42 colleagues from around the world have now told the tale of this discovery in a paper in Nature to be published Thursday and in a telephone news conference Wednesday.
The observations, they say, provide a new window into the process by which the most massive stars end their lives and give astronomers new clues on how to look for these rare events and catch them while they are still in their most explosive, formative stages.

”Most supernovas,” Dr. Soderberg explained, “are discovered and classified by their visible light, but that typically does not happen until theexplosion is a month or more old and has brightened enough to be seen over intergalactic distances.”

The true fireworks, she said, happen much earlier when a shock wave from the imploding core hits the star’s surface, producing so-called breakout light, which lasts only a few minutes.

“The physics of the explosion is encoded in the breakout light,” Dr. Soderberg said, adding that the chance that the Swift telescope was observing during those moments was “unfathomable.”
Astronomers now know, however, that X-rays from the breakout can be an early alert. “Supernova 2008D was the first to be found from its X-ray emission,” said Robert Kirshner, a supernova expert at the Harvard-Smithsonian Center for Astrophysics, referring to the supernova by its official name, “but if we build the right type of X-ray satellites, it won”t be the last supernova we find this way.”

“That is really what is so wonderful here,” he said.

”So new were the X-rays,” said Dr. Soderberg, “that she and her collaborators did not know they were looking at an incipient supernova until a day or two later and ground-based telescopes had seen it grow in visible light.”

“It was a baby supernova in that sense,” Dr. Soderberg said.
“Here was an object brand new. At first we didn”t recognize it.”

The supernova was of a sort known as Type Ibc, the rarest and most luminous of the explosions caused by the collapse of the cores of massive stars, theastronomers have concluded.
Another kind, known as Type Ia supernovas, are believed to result from the destruction of much smaller stars and are beloved of cosmologists who use them to track the expansion of the universe and effects of dark energy.

The star that died last January could have been 20 times as massive as the Sun or even bigger, Dr. Soderberg said.
It was probably a type called a Wolf-Rayet star.
They are very hot stars with surface temperatures of 50,000 degrees Fahrenheit or more and are often blowing gas away in strong winds. Dr. Soderberg described them as “very violent stars, very massive.”

Because it is gravity that stokes the thermonuclear furnace at the centers of stars, the more massive they are, the younger they die.
In the case of a star 10 or 20 times as massive as the Sun, it could be only a few million years. “These stars live fast and die young.
We don”t know if they leave a beautiful corpse,” Dr. Kirshner said.

Many of the elements necessary for life and its accessories, like carbon, oxygen, iron and gold, are produced in a thermonuclear frenzy during the final stages of these explosions, which then fling them into space to be incorporated into new stars, new planets, new creatures.

“If you”re wearing gold jewelry,” Dr. Kirshner said, “it came from a supernova explosion.”

Astronomers observe new red spot on Jupiter

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 20:36:00 +0000

Astronomers observe new red spot on Jupiter

A Hubble close-up of the three red ovals in an undated image. Jupiter has a new freckle -- a third red spot much smaller than the well-known Great Red Spot and a newer one dubbed Red Spot Jr., scientists said on Thursday.

Maggie Fox, Reuters
Published: Thursday, May 22

WASHINGTON :-
Jupiter has a new freckle -- a third red spot much smaller than the well-known Great Red Spot and a newer one dubbed Red Spot Jr., scientists said on Thursday.

The new spot arose from a white oval-shaped storm, and its change to a red color indicates that the storm is swirling up high into the Jovian atmosphere, the international team of planetary scientists said.

The images, taken by the orbiting Hubble space telescope and the Keck telescope in Hawaii, may support the idea that climate change is under way onJupiter, the largest planet in the solar system.
Amateur planet-gazer Christopher Go of Cebu in the Philippines helped locate the new development.

The gas giant's temperatures may be changing by 27 to 36 degrees Celsius, perhaps driving more turbulent storms.

While the Great Red Spot has been visible for as long as 350 years, Red Spot Jr. had only been around since 2006.
The team at the University of California Berkeley said all three spots represent storms and must be towering above the methane in Jupiter's atmosphere.

"If this spot and the Great Red Spot continue on their courses, they will encounter each other in August, and the small oval will either be absorbed or repelled from the Great Red Spot," Michael Wong of Berkeley, who worked on the study, said in a statement.

The Hubble Photos...Amazing

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 20:33:00 +0000

After correcting an initial problem with the lens, when the Hubble Space Telescope was first launched in 1990, the floating astro-observatory began to relay back to Earth, incredible snapshots of the 'final frontier' it was perusing.

Recently, astronauts voted on the top photographs taken by Hubble, in its 16-year journey so far.Remarking in the article from the Daily Mail, reporter Michael Hanlon says the photos 'illustrate that our universe is not only deeply strange, but also almost impossibly beautiful.'

Hubble telescope's top ten greatest space photographs

The Sombrero Galaxy - 28 million light years from Earth - was voted best picture taken by the Hubble telescope. The dimensions of the galaxy, officially called M104, are as spectacular as its appearance. It has 800 billion suns and is 50,000 light years across.

The Ant Nebula, a cloud of dust and gas whose technical name is Mz3, resembles an ant when observed using ground-based telescopes. The nebula lies within our galaxy between 3,000 and 6,000light years from Earth.

In third place is Nebula NGC 2392, called Eskimo because it looks like a face surrounded by a furry hood. The hood is, in fact, a ring of comet-shaped objects flying away from a dying star. Eskimo is 5,000light years from Earth.

At four is the Cat's Eye Nebula

The Hourglass Nebula, 8,000 light years away, has a pinched-in-the- middle
look because the winds that shape it are weaker at the centre.

In sixth place is the Cone Nebula. The part pictured here is 2.5 light years in
length (the equivalent of 23 million return trips to the Moon).

The Perfect Storm, a small region in the Swan Nebula, 5,500 light years away,
described as 'a bubbly ocean of hydrogen and small amounts of oxygen, sulphur and other elements'.

Starry Night, so named because it reminded astronomers of the Van Gogh painting. It is a halo of light around a star in the Milky Way.

The glowering eyes from 114 million light years away are the swirling cores of two merging galaxies called NGC 2207 and IC 2163 in the distant Canis Major constellation.

The Trifid Nebula. A 'stellar nursery', 9,000 light years from here, it is where new stars are being born.

Milky Way Loses Two Arms

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 19:59:00 +0000

New infrared images of the Milky Way show just two major spiral arms, Scutum-Centaus and Perseus, along with a newly discovered arm called Far 3kpc Arm.

ST. LOUIS :

For decades, astronomers have pictured our galaxy as sporting four major, spiral arms, however new images effectively sever two appendages, revealing the Milky Way has just two major arms.

"We're not proposing that they change the positions of the arms," said Robert Benjamin of the University of Wisconsin, Whitewater.
"What we're proposing is a change in the emphasis of the arms."
Benjamin will present his team's results today here at a meeting of the American Astronomical Society (AAS).

The results are among a handful of presentations at the meeting to paint an evolving picture of our galactic home base.

For instance, other results presented here by Thomas Dame of the Harvard-Smithsonian Center for Astrophysics (CfA) this week suggest a completely new arm of stars wraps around one side of the galactic center.
This new arm is a virtual twin of a known arm on the near side of the galactic center.
And another group led by Mark Reid of CfA has identified with more accuracy the location and relative distances of the stars within the spiral arms.

Spotlight on a galaxy

The Milky Way debuted as a spiral celebrity in 1951 when astronomical morphologist William Morgan of the Yerkes Observatory presented his results showing the galaxy's three arms of hot stars, which he were then namedPerseus, Orion and Sagittarius.

"Those were the first three arms of the spiral galaxy," Benjamin told SPACE.com.
"Actually, he got a standing ovation at the AAS meeting, which is something I've never seen."

Beginning in the 1960s and through the 1980s, several groups of scientists used radio astronomy to map out the Milky Way's structure, coming up with various results on how the spiral arms looked and the number of arms.

"For years, people created maps of the whole galaxy based on studying just one section of it, or using only one method," Benjamin said.
"Unfortunately, when the models from various groups were compared, they didn't always agree.
It's a bit like studying an elephant blind-folded."

The galactic image that stuck, Benjamin said, was one with the four spiral arms, now called Norma, Scutum-Centaurus, Sagittarius and Perseus.
Our sun lies near a small, partial arm called the Orion Arm, or Orion Spur, located between the Sagittarius and Perseus arms.

Spiral structure

The new survey of an extensive swath of the Milky Way was done with NASA's Spitzer Space Telescope, which detects infrared light.
All objects that emit any heat can be seen in infrared, and this wavelength penetrates dust, so the new mosaic includes 800,000 snapshots and more than 110 million stars.

Using a star-counting method, Benjamin and his colleagues noticed an increase in the number of stars in the direction of the Scutum-Centaurus Arm, but not in the direction of the Sagittarius and Norma arms.
(The fourth arm, Perseus, wraps around the outer portion of our galaxy and cannot be seen in the new Spitzer images.)
The two major arms, according to these findings, are the Scutum-Centaurus and Perseus arms.

The findings confirm an earlier observation by a team of astronomers, making a strong case that the Milky Way has two major spiral arms, a common structure for galaxies with bars.
These major arms have the greatest densities of both young, bright stars and older, so-called red-giant stars.

Phoenix Mars Lander

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 19:44:00 +0000

Phoenix Mars Lander

Mars is a cold desert planet with no liquid water on its surface. But in the Martian arctic, water ice lurks just below ground level. Discoveries made by the Mars Odyssey Orbiter in 2002 show large amounts of subsurface water ice in the northern arctic plain. The Phoenix lander targets this circumpolar region using a robotic arm to dig through the protective top soil layer to the water ice below and ultimately, to bring both soil and water ice to the lander platform for sophisticated scientific analysis.

(This artist's animation shows NASA's Phoenix Mars Lander taking a picture of its solar panel with its Surface Stereo Imager. The photographed area is highlighted. )

Objectives:

--Determine whether Life ever arose on Mars

--Characterize the Climate of Mars

--Characterize the Geology of Mars

--Prepare for Human Exploration

Study the History of Water in All its Phases

Currently, water on Mars' surface and atmosphere exists in two states: gas and solid. At the poles, the interaction between the solid water ice at and just below the surface and the gaseous water vapor in the atmosphere is believed to be critical to the weather and climate of Mars. Phoenix will be the first mission to collect meteorological data in the Martian arctic needed by scientists to accurately model Mars' past climate and predict future weather processes.

Liquid water does not currently exist on the surface of Mars, but evidence from Mars Global Surveyor, Odyssey and Exploration Rover missions suggest that water once flowed in canyons and persisted in shallow lakes billions of years ago. However, Phoenix will probe the history of liquid water that may have existed in the arctic as recently as 100,000 years ago. Scientists will better understand the history of the Martian arctic after analyzing the chemistry and mineralogy of the soil and ice using robust instruments.

Latest Images by NASA

NASA's Phoenix Mars Lander did a small amount of excavation as it touched down on pebbly north polar terrain on the Red Planet, as shown in this close-up view of one of the lander's three footpads.

This image shows a polygonal pattern in the ground near NASA's Phoenix Mars Lander, similar in appearance to icy ground in the arctic regions of Earth.

This image, one of the first captured by NASA's Phoenix Mars Lander, shows the vast plains of the northern polar region of Mars. The flat landscape is strewn with tiny pebbles and shows polygonal cracking, a pattern seen widely in Martian high latitudes and also observed in permafrost terrains on Earth. The polygonal cracking is believed to have resulted from seasonal freezing and thawing of surface ice.

Historical Log!

Launch Date-Name-Country-Result-Reason
1960-Korabl 4-USSR (flyby)-Failure-Didn't reach Earth orbit

1960-Korabl 5-USSR (flyby)-Failure-Didn't reach Earth orbit

1962-Korabl 11-USSR (flyby)-Failure-Earth orbit only; spacecraft broke apart

1962-Mars 1-USSR (flyby)-Failure-Radio Failed

1962-Korabl 13-USSR (flyby)-Failure-Earth orbit only; spacecraft broke apart

1964-Mariner 3-US (flyby)-Failure-Shroud failed to jettison

1964-Mariner 4-US (flyby)-Success-Returned 21 images

1964-Zond 2-USSR (flyby)-Failure-Radio failed

1969-Mars 1969A-USSR-Failure-Launch vehicle failure

1969-Mars 1969B-USSR-Failure-Launch vehicle failure

1969-Mariner 6-US (flyby)-Success-Returned 75 images

1969-Mariner 7-US (flyby)-Success-Returned 126 images

1971-Mariner 8-US-Failure-Launch failure

1971-Kosmos 419-USSR-Failure-Achieved Earth orbit only

1971-Mars 2 Orbiter/Lander-USSR-Failure-Orbiter arrived, but no useful data and Lander destroyed

1971-Mars 3 Orbiter/Lander-USSR-Success-Orbiter obtained approximately 8 months of data and lander landed safely, but only 20 seconds of data

1971-Mariner 9-US-Success-Returned 7,329 images

1973-Mars 4-USSR-Failure-Flew past Mars

1973-Mars 5-USSR-Success-Returned 60 images; only lasted 9 days

1973-Mars 6 Orbiter/Lander-USSR-Success/Failure-Occultation experiment produced data and Lander failure on descent

1973-Mars 7 Lander-USSR-Failure-Missed planet; now in solar orbit.

1975-Viking 1 Orbiter/Lander-US-Success-Located landing site for Lander and first successful landing on Mars

Historical Log (Cont.)

Launch Date-Name-Country-Result-Reason
1975-Viking 2 Orbiter/Lander-US-Success-Returned 16,000 images and extensive atmospheric data and soil experiments

1988-Phobos 1 Orbiter-USSR-Failure-Lost en route to Mars

1988-Phobos 2 Orbiter/Lander-USSR-Failure-Lost near Phobos

1992-Mars Observer-US-Failure-Lost prior to Mars arrival

1996-Mars Global Surveyor-US-Success-More images than all Mars Missions

1996-Mars 96-USSR-Failure-Launch vehicle failure

1996-Mars Pathfinder-US-Success-Technology experiment lasting 5 times longer than warranty

1998-Nozomi-Japan-Failure-No orbit insertion; fuel problems

1998-Mars Climate Orbiter-US-Failure-Lost on arrival

1999-Mars Polar Lander-US-Failure-Lost on arrival

1999-Deep Space 2 Probes (2)-US-Failure-Lost on arrival (carried on Mars Polar Lander)

2001-Mars Odyssey-US-Success-High resolution images of Mars

2003-Mars Express Orbiter/Beagle 2 Lander-ESA-Success/Failure-Orbiter imaging Mars in detail and lander lost on arrival

2003-Mars Exploration Rover - Spirit-US-Success-Operating lifetime of more than 15 times original warranty

2003-Mars Exploration Rover - Opportunity-US-Success-Operating lifetime of more than 15 times original warranty

2005-Mars Reconnaissance Orbiter-US-Success-Returned more than 26 terabits of data (more than all other Mars missions combined)

2007-Phoenix Mars Lander-US-TBD-

Astronomy Picture Discover the cosmos!

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 19:35:00 +0000

Discover the cosmos! photograph of our fascinating universe is featured, along with a brief explanation

Hoag's Object: A Strange Ring Galaxy

Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How Hoag'sObject formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and perturbative gravitational interactions involving an unusually shaped core. The above photo taken by the Hubble Space Telescope in July 2001 reveals unprecedented details of Hoag's Object and may yield a better understanding. Hoag's Object spans about 100,000 light years and lies about 600 million light years away toward the constellation of Serpens. Coincidentally, visible in the gap (at about one o'clock) is yet another ring galaxy that likely lies far in the distance.

Venus Beyond the Storm

A thunderstorm, lightning, a bright star and a bright planet all graced an evening sky for a short while near Bismarck, North Dakota, USA two weeks ago. Thick thunderclouds from a passing storm are the origin of a strong cloud to ground lightning strike. Small areas of rain darken portions of the orange sunset, visible at the horizon above the vast prairie. The planet Venus peeks below the clouds on the lower left of the image. Blue sky shines high above the distant storm, streaked with high white cirrus clouds. The bright star Arcturus glitters near the image top, just left of center. Just a few minutes later, only a memory and this picture remained

Pluto & Charon Eclipse a Triple Star

Explanation

Occasionally, a planet in our Solar System will pass in front of a bright star. Since stars and planets take up so little space on the sky, such events are quite rare. Two months ago, however, Pluto and its large moon Charon passed in front of a comparativelybright triple star system known as P126. By noting how P126 A dimmed, the event was useful for studying Pluto's relatively unknown atmosphere. A Very Large Telescope in Chile using a deformable mirror to counter the blurring effect of Earth's atmosphere captured the above image.

X-Rays From Tycho's Supernova Remnant

In 1572, Danish astronomer Tycho Brahe recorded the sudden appearance of a bright new star in the constellation Cassiopeia. The new star faded from view over a period of months and is believed to have been a supernova, one of the last stellar explosions seen in our Milky Way galaxy. Now known as Tycho's Supernova Remnant, the expanding debris cloud is shown in this detailed false-color x-ray image from the orbiting Chandra Observatory. Represented in blue, the highest energy x-rays come from shocked regions along the outer edges of the supernova remnant, corresponding to gas at temperatures of 20 million degrees Celsius. X-rays from cooler gas (only 10 million degrees or so!) dominate the remnant's interior. Unlike some other supernova remnants, no hot central point source can be found, supporting the theory that the origin of this stellar explosion was a runaway nuclear detonation that ultimately destroyed a white dwarf star. At a distance of about 7,500 light-years, Tycho's Supernova Remnant appears to be nearly 20 light-years across. This x-ray picture's field of view slightly cuts off the bottom of the generally spherical cloud

Aristarchus Plateau

Explanation
Anchored in the vast lava flows of the Moon's Oceanus Procellarum lies the Aristarchus Plateau. Recorded from a backyard observatory on planet Earth, this sharp, amazingly colorful view nicely captures the geologically diverse area, including the brownish plateau, Aristarchus and Herodotus craters, and the meandering Vallis Schroteri. Thebright impact crater at the corner of the plateau is Aristarchus, a young crater 42 kilometers wide and 3 kilometers deep, surrounded by a radial system of light-colored rays. Only slightly smaller, lava flooded Herodotus crater is above and to the left. A valley or rille feature likely carved by rapidly flowing lava or a collapsed lava tunnel, Vallis Schroteri begins just to the right of Herodotus and winds across the plateau for about 160 kilometers, eventually turning toward the top of the picture and the shadow of the lunar terminator. Aristarchus Plateau itself is like a rectangular island about 200 kilometers across, raised up to 2 kilometers or so above the smooth surface of the lunar Ocean of Storms

Glimpses of a rare celestial event..solar Ecplise

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 12:39:00 +0000

The next solar eclipse -- a partial one -- will occur on January 26 next year but the phenomenon will be marginally visible from eastern and southernIndia.

India will witness a partial eclipse of the Sun beginning in the northeast of India on Friday.
It will begin at 4:03 pm in Delhi. It will last for about two hours with maximum impact at 5.02 pm. In the rest of the country, the partial eclipse will be visible a few minutes later.

However, some parts of the world will witness a rare total solar eclipse -- when the moon will pass directly between the earth and the sun.

The eclipse will begin in Arctic Canada and sweep across Greenland, western Siberia, Mongolia and central China.

Viewers all across the globe can see the eclipse as it happens on NASA TV and by logging on to www.nasa.gov. The US space agency has made arrangements to telecast live images of the rare celestial event.

Image: Indians will miss this sight -- A total solar eclipse

August 01, 2008

According to Nehru Planetarium director Rathnasree, the maximum obscuration of the sun will occur at Sibsagar in Assam..
The biggest and last phase of the eclipse will be visible from most parts of the country, except Nagaland and Mizoram, where it ends after sunset, she said.

The southern parts of India will see between 20 to 40 per cent of the sun's diameter while the northern parts of the country will see between 40 to 70 per cent of the sun's diameter.

Image: A combo photograph of the partial solar eclipse.

August 01, 2008

People must also avoid watching the eclipse through sunglasses, single or multiple layers, smoked glass, colour film or black-and-white film that contains no silver or photographic negatives with images on them.
The Nehru Planetarium, in collaboration with the Amateur Astronomers Association, Delhi will be conducting public sky-watch for the eclipse from the Jantar Mantar, the planetarium and the India Gate area.

Image: A multiple exposure photograph shows the progress of a total solar eclipse. The sequence begins at the upper left.

Some Bizarre Things in Space

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 12:37:00 +0000

From miniature black holes to distortions in the fabric of space-time, from galaxies that are eating each other to matter that can neither be seen nor detected directly…space is full of many strange things. And here are some of the strangest.

1. Neutrinos

Neutrinos are electrically neutral, virtually mass-less elementary particles that can pass through miles of lead unhindered. Some are passing through your body as you read this. These “phantom” particles are produced in the inner fires of burning, healthy stars as well as in the supernova explosions of dying stars. Detectors are being embedded underground, beneath the sea, or into a large chunk of ice as part of IceCube, a neutrino-detecting project.

2. Galactic Cannibalism

Like life on Earth, galaxies can “eat” each other and evolve over time. The Milky Way’s neighbor, Andromeda, is currently dining on one of its satellites. More than a dozen star clusters are scattered throughout Andromeda, the cosmic remains of past meals. The image above is from a simulation of Andromeda and our galaxy colliding, an event that will take place in about 3 billion years.

3. Gravity Waves

Gravity waves are distortions in the fabric of space-time predicted by Albert Einstein’s theory of general relativity. The waves travel at the speed of light, but they are so weak that scientists expect to detect only those created during colossal cosmic events, such as black hole mergers like the one shown above. LIGO and LISA are twodetectors designed to spot the elusive waves.

4. Exoplanets

Until about the early 1990s, the only known planets in the universe were the familiar ones in our solar system. Astronomers have since identified more than 190 extrasolar planets (as of June 2006). They range from gargantuan gas worlds whose masses are just shy of being stars to small, rocky ones orbiting dim, red dwarfs. Searches for a second Earth, however, have so far turned up empty. Astronomers generally believe that better technology is likely to eventually reveal several worlds similar to our own.

5. Dark Matter

Scientists think it makes up the bulk of matter in the universe, but it can neither be seen nor detected directly using current technologies. Candidates range from light-weight neutrinos to invisible black holes. Some scientists question whether dark matter is even real, and suggest that the mysteries it was conjured to solve could be explained by a better understanding of gravity.

6. Cosmic Microwave Background

Also known as the CMB, this radiation is a primordial leftover from the Big Bang that birthed the universe. It was first detected during the 1960s as a radio noise that seemed to emanate from everywhere in space. The CMB is regarded as one of the best pieces of evidence for the theoretical Big Bang. Recent precise measurements by the WMAP project place the CMB temperature at -455 degrees Fahrenheit (-270 Celsius).

]7. Mini Black Holes

If a radical new “braneworld” theory of gravity is correct, then scattered throughout our solar system are thousands of tiny black holes, each about the size of an atomic nucleus. Unlike their larger brethren, these mini-black holes are primordial leftovers from the Big Bang and affect space-time differently because of their close association with a fifth dimension.

8. Anti-matter

Like Superman’s alter-ego, Bizzaro, the particles making up normal matter also have opposite versions of themselves. An electron has a negative charge, for example, but its anti-matter equivalent, the positron, is positive. Matter and anti-matter annihilate each other when they collide and their mass is converted into pure energy by Einstein’s equation E=mc2. Some futuristic spacecraft designs incorporate anti-matter engines.

9. Vacuum Energy

Quantum physics tells us that contrary to appearances, empty space is a bubbling brew of “virtual” subatomic particles that are constantly being created and destroyed. The fleeting particles endow every cubic centimeter of space with a certain energy that, according to general relativity, produces an anti-gravitational force that pushes space apart. Nobody knows what’s really causing the accelerated expansion of the universe, however.

10. Quasars

These bright beacons shine to us from the edges of the visible universe and are reminders to scientists of our universe’s chaotic infancy. Quasars release more energy than hundreds of galaxies combined. The general consensus is that they are monstrous black holes in the hearts of distant galaxies. This image is of quasar 3C 273, photographed in 1979

Amazing Views of Jupiter

noreply@blogger.com (Imran Malik) — Wed, 02 Dec 2009 12:29:00 +0000

Jupiter's moon Io floats above the cloudtops of Jupiter in this image captured January 1, 2001. The image is deceiving: there are 350,000 kilometers - roughly 2.5 Jupiters - between Io and Jupiter's clouds. Io is about the size of our own moon

Jupiter is in the news again, this time because its "Baby Red Spot" - a storm less than a year old - appears to have been swallowed up by the massive storm known as the Great Red Spot. This is good occasion to share some of the best photographs of Jupiter and its larger system of rings and moons, as seen by various probes and telescopes over the past 30 years

This image of Jupiter's moon Europa rising above Jupiter was captured by the New Horizons spacecraft in February just after it passed Jupiter on its way to Pluto and the outer Solar System.

The gibbous phase of Jupiter's moon Europa. The robot spacecraft Galileo captured this image mosaic during its mission orbiting Jupiter from 1995 - 2003. Evidence and images from the Galileo spacecraft, indicated that liquid oceans might exist below the icy surface.

This view of the icy surface of Jupiter's moon, Europa, is a mosaic of two pictures taken by the Solid State Imaging system on board the Galileo spacecraft during a close flyby of Europa on February 20, 1997. The area shown is about 14 kilometers by 17 kilometers (8.7 miles by 10.6 miles), and has a resolution of 20 meters (22 yards) per pixel. One of the youngest features seen in this area is the double ridge cutting across the picture from the lower left to the upper right. This double ridge is about 2.6kilometers (1.6 miles) wide and stands some 300 meters (330 yards) high.

A composite of several images taken in several colors by the New Horizons Multispectral Visual Imaging Camera, or MVIC, illustrating the diversity of structures in Jupiter's atmosphere, in colors similar to what someone "riding" on New Horizons would see. It was taken near the terminator, the boundary between day and night, and shows relatively small-scale, turbulent, whirlpool-like structures near the south pole of the planet. The dark "holes" in this region are actually places where there is very little cloud cover, so sunlight is not reflected back to the camera.

This image, acquired during Galileo's ninth orbit around Jupiter, shows two volcanic plumes on Io. One plume was captured on the bright limb or edge of the moon, erupting over a caldera (volcanic depression) named Pillan Patera. The plume seen by Galileo is 140 kilometers (86 miles) high, and was also detected by the Hubble Space Telescope. The second plume, seen near the terminator, the boundary between day and night, is called Prometheus. The shadow of the airborne plume can be seen extending to the right of the eruption vent.

A part of the southern hemisphere of Io, seen by the spacecraft Voyager at a range of 74,675 km. In the foreground is gently undulating topography, while in the back-ground are two mountains with their near faces brightly illuminated by the sun. The mountain in the right is approximately 150 km across at its base and its height is probably in excess of 15 km which would make it higher than any mountain on Earth.

This five-frame sequence of New Horizons images captures the giant plume from Io's Tvashtar volcano. Snapped by the probe's Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Jupiter earlier this year, this first-ever "movie" of an Io plume clearly shows motion in the cloud of volcanic debris, which extends 330 kilometers (200 miles) above the moon's surface. Only the upper part of the plume is visible from this vantage point - the plume's source is 130 kilometers (80 miles) below the edge of Io's disk, on the far side of the moon.

A volcanic plume rises over 300 kilometers above the horizon of Jupiter's moon Io in this image from cameras onboard the New Horizons spacecraft. The volcano, Tvashtar, is marked by the bright glow (about 1 o'clock) at the moon's edge, beyond the terminator or night/day shadow line. The shadow of Io cuts across theplume itself. Also capturing stunning details on the dayside surface, the high resolution image was recorded when the spacecraft was 2.3 million kilometers from Io. Later it was combined with lower resolution color data by astro-imager Sean Walker to produce this sharp portrait of the solar system's most active moon.

Jupiter's moon Io, seen by NASA's Galileo spacecraft against a backdrop of Jupiter's cloud tops, which appear blue in this false-color composite.

The first color movie of Jupiter from NASA's Cassini spacecraft shows what it would look like to peel the entire globe of Jupiter, stretch it out on a wall into the form of a rectangular map, and watch its atmosphere evolve with time. The brief movie clip spans 24Jupiter rotations between Oct. 31 and Nov. 9, 2000. The darker blips that appear are several moons and their shadows.

Jupiter's Great Red seen by NASA's Voyager spacecraft. July, 1979 Around the northern boundary a white cloud is seen, which extends to east of the region. The presence of this cloud prevents small cloud vortices from circling the spot in the manner seen in the Voyager 1 encounter. Another white oval cloud (different from the one present in this position three months ago) is seen south of the Great Red Spot. This image was taken on July 6, 1979 from a range of 2,633,003 kilometers. The Red Spot is 20,000 km across.[/I

Awesome Close-Ups of the Sun

noreply@blogger.com (Imran Malik) — Tue, 24 Nov 2009 19:10:00 +0000

Awesome Close-Ups of the Sun

The sun (not the earth!) is the center of our solar system. Here are some interesting facts of this quintessential planet to live on earth that we so easily take for granted.

* Containing more than 99.8% of the total mass of the Solar System, the Sun is by far the largest object in the Solar System.
* 109 Earths would be required to even fit across the Sun’s disk, and the Sun’s interior could hold over 1.3 million Earths.
* Within the core of the Sun, the temperature (15,000,000 K) and pressure (340 billion times Earth’s air pressure at sea level) of it is so intense that nuclear reactions actually take place.
* The Sun’s energy output, produced by these nuclear fusion reactions, is approximately 3.86e33 ergs/second or 386 billion billion megawatts.
* This energy, released as heat as well as light, takes a million years to reach the surface.
* The Sun also emits low density streams of particles, also known as the solar wind. These winds blow through the solar system at 450 km/sec and consist mostly of electrons and protons.
* The Sun consists of the core, photosphere, chromosphere and corona, each with differing temperatures and components.
* Existing for about 4 and a half billion years, it has burnt up about half of the hydrogen in its core. This leaves the Sun’s life expectancy to 5 billion more years, at which time, the Sun’s elements will “swell” up, swallow Earth, and eventually die off into a small white dwarf.

Martian Skies!

noreply@blogger.com (Imran Malik) — Tue, 24 Nov 2009 12:23:00 +0000

June 19th announcement by NASA of the discovery of water ice on Mars by its Phoenix Lander probe made big news everywhere. The discovery involved the observation of water ice sublimating into the air - that is, the water went from solid to vapor state without reaching the liquid stage. The Martian atmosphere has perfect conditions for sublimation - extremely thin, dry and cold. How cold? Well, you can check the Live Martian Weather Report, with data from a station on board the Phoenix Lander. Today will see a high temperature of a toasty -26 degrees F.

What more do we know about Mars' atmosphere? It's hundreds of times thinner than Earth's atmosphere and is made of 95% carbon dioxide, 3% nitrogen, 1.6% argon, and contains traces of oxygen, water, and methane. We also know, from observations that it can support dust storms, dust devils, clouds and gusty winds. With an amazing number of six current live probes exploring Mars (two rovers, a lander, and three orbiters), there are many thousands ofimages available. Only a few, however show atmospheric phenomena. Presented here are some of the best images of Martian atmosphere (and beyond) in action.

High, wispy clouds cover a large portion of Mars, seen in this, the first true-colour image of Mars generated with the OSIRIS orange (red), green and blue color filters. The image was acquired by an instrumenton the ESA's Rosetta probe on Feb. 24, 2007 from a distance of about 240,000 km. Image resolution is about 5 km/pixel. (Credits: ESA © 2007 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA)

Mars' northern orange sky and horizon, seen by NASA's Phoenix Mars Lander. The lander's solar panel and Robotic Arm with a sample in the scoop are also visible. The image was taken by the lander's Surface Stereo Imager looking west during Phoenix's Sol 16 (June 10, 2008), or the 16thMartian day after landing. The image was taken just before the sample was delivered to the Optical Microscope. (NASA/JPL-Caltech/University of Arizona/Texas A&M University)

The brownish gray sky at sunset as it would be seen by an observer on Mars - true color mosaic taken by Mars Pathfinder on sol 24 (June 22, 1996) The sky near the sun is a pale blue color. (NASA/JPL)

High ice cloud over Mars' limb. This composite of red and blue Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired on 6 July 2005 shows an isolated water ice cloud extending more than 30 kilometers (more than 18 miles) above the Martian surface. Clouds such as this are common in late spring over the terrain located southwest of the Arsia Mons volcano. (NASA/JPL/Malin Space Science Systems)

Clouds over crater - the dust storm season in the southern hemisphere of Mars was well underway. This image of an unnamed crater southeast of Hellas Basin shows the encroachment of a storm in the region. Image acquired in 2001 by Mars Odyssey orbiter (17 meter/pixel resolution). (NASA/JPL/ASU)

Dust devil from above. This image taken by the Hi-RISE Camera aboard NASA's Mars Reconnaissance Orbiter catches a dust devil blowing across theMartian surface. Dust devils generally form in the afternoon because the sunlight needs sufficient time to warm the surface. When this image was taken, the local time was about 3:08 p.m. The bright material is the dust within the vortex, and a dark shadow cast by the dust devil is visibleto the left. The diameter of this dust devil is about 200 meters, but at the surface it is probably much smaller. Based on the length of the shadow in this image, the dust devil is on the order of 500 meters tall. (NASA/JPL/University of Arizona)

Martian skies seen above a rolling horizon in this image, part of a larger image called the "McMurdo" panorama, taken in the Martian winter of 2006 by NASA's Mars Exploration Rover Spirit. The tracks in the soil are from Spirits wheels as it rolled through the area earlier. (NASA/JPL/Cornell)

Clouds above the rim of "Endurance Crater" in this image from NASA's Mars Exploration Rover Opportunity. These clouds occur in a region of strong vertical shear. The cloud particles (ice in thismartian case) fall out, and get dragged along away from the location where they originally condensed, forming characteristic streamers. Opportunity took this picture with its navigation camera during the rover's 269thmartian day (Oct. 26, 2004). (NASA/JPL)

Early Spring Dust Storms at the North Pole of Mars. Early spring typically brings dust storms to northern polar Mars. As the north polar cap begins to thaw, the temperature difference between the cold frost region and recently thawed surface results in swirling winds. The choppy dust clouds of several dust storms are visible in this mosaic of images taken by the Mars Global Surveyor spacecraft in 2002. The white polar cap is frozen carbon dioxide. (NASA/JPL/Malin Space Science Systems)

An exaggerated color image mosaic of images from NASA's Mars Rover Opportunity. The clouds can be composed of either carbon dioxide ice or water ice, and can move swiftly across the sky. (NASA/JPL/Cornell)

Large dust storms cover much of Mars' surface in this July, 2001 image, acquired by NASA's Mars Global Surveyor Mars Orbiter Camera. By early July, themartian atmosphere was so hazy that opportunities for high resolution imaging of the planet were very limited. (NASA/JPL/Malin Space Science Systems)

The air is certainly thick enough to fill a parachute. On May 25th, 2008, the HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this dramatic oblique image of the arrival of its sister probe from NASA, the Phoenix Lander, descending on its parachute. Phoenix and its parachute can be barely seen in the larger image with 10 km wide crater informally called "Heimdall" in the background. Although it appears that Phoenix is descending into the crater, it is actually about 20 kilometers in front of the crater. Given the position and pointing angle of MRO, Phoenix is at about 13 km above the surface, just a few seconds after the parachute opened. (NASA/JPL/University of Arizona)

On May 19th, 2005, NASA's Mars Exploration Rover Spirit captured this stunning view as the Sun sank below the rim of Gusev crater on Mars. This Panoramic Camera mosaic was taken around 6:07 in the evening of the rover's 489th martian day, or sol. Spirit was commanded to stay awake briefly after sending that sol's data tothe Mars Odyssey orbiter just before sunset. The image is a false color composite, showing the sky similar to what a human would see, but with the colors slightly exaggerated. (NASA/JPL/Texas A&M/Cornell)

Higher in the Martian skies, we see one of its two moons. The HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this dramatic view of the Martian moon, Phobos, on 23 March 2008, from a distance of 6,800 kilometers. The illuminated part of Phobos is about 21 km across. The most prominent feature is the large impact crater Stickney, in the upper left. With a diameter of 9 km, it is the largest feature on Phobos. (NASA/JPL/University of Arizona)

Even higher in the Martian sky, the Earth and Moon hang in space, as seen from Mars. The HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this image at 5:20 a.m. MST on October 3rd, 2007, at a range of 142 million kilometers, while orbiting Mars

>> Most fascinating Galaxies of the Universe <<

noreply@blogger.com (Imran Malik) — Tue, 24 Nov 2009 11:28:00 +0000

Supernova 1987A

Two decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years: a doomed star, called Supernova 1987A. This image shows the entire region around the supernova. The most prominent feature in the image is a ring with dozens of bright spots. A shock wave of material unleashed by the stellar blast is slamming into regions along the ring's inner regions, heating them up, and causing them to glow. The ring, about a light-year across, was probably shed by the star about 20,000 years before it exploded. In the next few years, the entire ring will be ablaze as it absorbs the full force of the crash. The glowing ring is expected to become bright enough to illuminate the star's surroundings, providingastronomers with new information on how the star expelled material before the explosion. The image was taken in December 2006 with Hubble's Advanced Camera for Surveys. (Credit: NASA, ESA, and R. Kirshner; Harvard-Smithsonian Center for Astrophysics)

Galaxy NGC 1512

A barred spiral galaxy located some 30 million light years away toward the constellation Horologium, Galaxy NGC 1512 is bright enough to be seen with amateur telescopes. The galaxy is some 70,000 light years across, which is nearly as large as our own Milky Way galaxy. The core of the galaxy is remarkable for its "circumnuclear" starburst ring, which is an amazing circle of young star clusters that spans some 2400light years across. Galaxy "starbursts" are episodes of vigorous formation of new stars and are found in various galaxy environments.

Galaxy NGC 3370

A dusty spiral galaxy located some 98 million light years away toward the constellation Leo, the center of NGC 3370 shows well delineated dust lanes and an uncommonly ill-defined nucleus. This view of NGC 3370 was obtained by the Hubble Space Telescope using the Advanced Camera for surveys and is sharp enough to identify individual Cepheid variable stars in the galaxy. Cepheid variable stars are used to establish extragalactic distances. In 1994, a Type Ia sypernova exploded in NGC 3370. (Credit: NASA, The Hubble Heritage Team and A. Riess; STScI)

M81

The big and beautiful spiral galaxy M81, in the northern constellation Ursa Major, is one of the brightest galaxies visible in the skies of planet Earth. This superbly detailed view reveals its bright nucleus, grand spiral arms and sweeping cosmic dust lanes with a scale comparable to the Milky Way. Hinting at a disorderly past, a remarkable dust lane runs straight through the disk, below and right of the galactic center, contrary to M81's other prominent spiral features. The errant dust lane may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82. Scrutiny of variable stars in M81 (aka NGC 3031) has yielded one of the best determined distances for an external galaxy -- 11.8 million light-years.

Hoag's Object

A non-typical galaxy of the type known as a ring galaxy, the appearance of Hoag's Object has interested amateur astronomers as much as its uncommon structure has fascinated professionals. Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How Hoag's Object formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and perturbative gravitational interactions involving an unusually shaped core. The above photo taken by theHubble Space Telescope in July 2001 reveals unprecedented details of Hoag's Object and may yield a better understanding. Hoag's Object spans about 100,000light years and lies about 600 million light years away toward the constellation of Serpens. Coincidentally, visible in the gap is yet another ring galaxy that likely lies far in the distance.

The Sombrero Galaxy

The Sombrero Galaxy (also known as M104 or NGC 4594) is an unbarred spiral galaxy in the constellation Virgo. It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk. The dark dust laneand the bulge give this galaxy the appearance of a sombrero. The galaxy has an apparent magnitude of +9.0, making it easily visible with amateur telescopes. The large bulge, the central supermassive black hole,and the dust lane all attract the attention of professional astronomers.

Black Eye Galaxy

A spiral galaxy in the Coma Berenices constellation, Messier 64, the famous "Black Eye" galaxy or the "Sleeping Beauty galaxy," has a spectacular dark band of absorbing dust in front of the galaxy's bright nucleus. It is well known among amateurastronomers because of its appearance in small telescopes.

2MASX J00482185-2507365 occulting pair

The 2MASX J00482185-2507365 occulting pair is a pair of overlapping spiral galaxies found in the vicinity of NGC 253, the Sculptor Galaxy. Both galaxies are more distant than NGC 253, with the background galaxy, 2MASX J00482185-2507365, lying at redshift z=0.06, and the foreground galaxy lying between NGC 253 and the background galaxy (0.0008 <>

The Whirlpool Galaxy

Also known as Messier 51a, M51a, or NGC 5194, the Whirlpool Galaxy is an interacting grand-design spiral galaxy located at a distance of approximately 23 million light-years in theconstellation Canes Venatici. It is one of the most famous spiral galaxies in the sky. The galaxy and its companion (NGC 5195) are easily observed by amateur astronomers, and the two galaxies may even be seen with binoculars. The Whirlpool Galaxy is also a popular target for professional astronomers , who study it to further understanding of galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions.

Grand spiral galaxy

Also known as NGC 123, this fascinating galaxy is dominated by millions of bright stars and dark dust, caught up in a gravitational swirl of spiral arms rotating about the center. Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes of dense interstellar dust can be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts of interstellar gas, together wielding such high mass that they dominate the dynamics of the inner galaxy. Invisible are even greater amounts of matter in a form we don't yet know - pervasive dark matter needed to explain the motions of the visible in the outer galaxy.

10 things you don’t know about black holes

noreply@blogger.com (Imran Malik) — Wed, 11 Nov 2009 19:41:00 +0000

Ah, black holes. The ultimate shiver-inducer of the cosmos, out-jawing sharks, out-ooking spiders, out-scaring… um, something scary. But we’re fascinated by ‘em, have no doubt - even if we don’t understand a whole lot about them.

1) It’s not their mass, it’s their size that makes them so strong.

OK, first, a really quick primer on black holes. Bear with me!

The most common way for a black hole to form is in the core of a massive star. The core runs out of fuel, and collapses. This sets off a shockwave, blowing up outer layers of the star, causing a supernova. So the star’s heart collapses while the rest of it explodes outwards

As the core collapses, its gravity increases. At some point, if the core is massive enough (about 3 times the mass of the Sun), the gravity gets so strong that right at the surface of the collapsing core the escape velocity increases to the speed of light. That means that nothing can escape the gravity of this object, not even light. So it’s black. And since nothing can escape, well, read the quotation at the top of the page.

The region around the black hole itself where the escape velocity equals the speed of light is called the event horizon. Any event that happens inside it is forever invisible.

OK, so now you know what one is, and how they form. Now, the video showing why they have such strong gravity.

Sure, the mass is important, but sometimes it’s the little things that count.

2) They’re not infinitely small.

So OK, they’re small, but how small are they?

I was writing about black holes in my previous job, and we got in a fun discussion over just what we meant by black hole: did we mean the object itself that collapses down to a mathematical point, or the event horizon surrounding it? I said the event horizon, but my boss said it was the object. I decided she had a point (HAHAHAHAHA! A “point”! Man, I kill me), and made sure that when I wrote about the event horizon versus the black hole itself I was making myself clear.

Like I said above, to the collapsing core, its clock keeps ticking, so it sees itself collapsing all the way down to a point, even if the event horizon has some finite size.

What happens to the core? The actual mass that collapsed?

Out here, we’ll never know for sure. We can’t see in, and it sure enough isn’t gonna send any info out. But our math in these situations is pretty good, and we can at least apply them to the collapsing core, even when it’s smaller than the event horizon.

It will continue to collapse, and the gravity increases. Smaller, smaller… and when I was a kid I always read that it collapses all the way down to a geometric dot, an object with no dimensions at all. That really bugged me, as you can imagine… as well it should. Because it’s wrong.

At some point, the collapsing core will be smaller than an atom, smaller than a nucleus, smaller than an electron. It’ll eventually reach a size called the Planck Length, a unit so small that quantum mechanics rules it with an iron fist. A Planck Length is a kind of quantum size limit: if an object gets smaller than this, we literally cannot know much about it with any certainty. The actual physics is complicated, but pretty much when the collapsing core hits this size, even if we could somehow pierce the event horizon, we couldn’t measure its real size. In fact, the term “real size” doesn’t really mean anything at this kind of scale. If the Universe itself prevents you from measuring it, you might as well say the term has no meaning.

And how small is a Planck Length? Teeny tiny: about 10-35 meters. That’s one one-hundred quintillionth the size of a proton.

So if someone says a black hole has zero size, you can be all geeky and technical and say, not really, but meh. Close enough.

3) They’re spheres. And they’re definitely not funnel shaped.

The gravity you feel from an object depends on two things: the object’s mass, and your distance from that object. This means that anyone at a given distance from a massive object - say, a million kilometers - would feel the same force of gravity from it. That distance defines a sphere around an object: anyone on that sphere’s surface would feel the same gravity from the object at the center.

The size of an event horizon of a black hole depends on the gravity, so really the event horizon is a sphere surrounding the black hole. From the outside, if you could figure out how to see the event horizon in the first place, it would look like a pitch black sphere.

Some people think of black holes as being circles, or worse, funnel-shaped. The funnel thing is a misconception from people trying to explain gravity as a bending in space, and they simplify things by collapsing 3D space into 2D; they say the space is like a bed sheet, and objects with mass bend space the same way that a massive object (a bowling ball, say) will warp a bed sheet. But space is not 2D, it’s 3D (even 4D if you include time) and so this explanation can confuse people about the actual shape of a black hole event horizon.

4) Black holes spin!

It’s kind of an odd thought, but black holes can spin. Stars rotate, and when the core collapses the rotation speeds way, way up (the usual analogy is that of an ice skater who brings in his arms, increasing his rotation rate). As the core of the star gets smaller it rotates more rapidly. If it doesn’t quite have enough mass to become a black hole, the matter gets squeezed together to form a neutron star, a ball of neutrons a few kilometers across. We have detected hundreds of these objects, and they tend to spin very rapidly, sometimes hundreds of times a second!

The same is true for a black hole. Even as the matter shrinks down smaller than the event horizon and is lost to the outside Universe forever, the matter is still spinning. It’s not entirely clear what this means if you’re trying to calculate what happens to the matter once it’s inside the event horizon. Does centrifugal force keep it from collapsing all the way down to the Planck length? The math is fiendish, but do-able, and implies that matter falling in will hit matter inside the event horizon trying to fall further but unable to due to rotation, This causes a massive pile up and some pretty spectacular fireworks… that we’ll never see, because its on the other side of infinity.

5) Near a black hole, things get weird

The spin of the black hole throws a monkey in the wrench of the event horizon. Black holes distort the fabric of space itself, and if they spin that distortion itself gets distorted. Space can get wrapped around a black hole - kind of like the fabric of a sheet getting caught up in a rotating drill bit.

This creates a region of space outside the event horizon called the ergosphere. It’s an oblate spheroid, a flattened ball shape, and if you’re outside the event horizon but inside the ergosphere, you’ll find you can’t sit still. Literally. Space is being dragged past you, and carries you along with it. You can easily move in the direction of the rotation of the black hole, but if you try to hover, you can’t. In fact, inside the ergosphere space is moving faster than light! Matter cannot move that fast, but it turns out, according to Einstein, space itself can. So if you want to hover over a black hole, you’d have to move faster than light in the direction opposite the spin. You can’t do that, so you have to move with the spin, fly away, or fall in. Those are your choices.

6) Approaching a black hole can kill you in fun ways. And by fun, I mean gruesome, horrifying, and really really ookie.

Sure, if you get too close, plop! You fall in. But even if you keep your distance you’re still in trouble…

Gravity depends on distance. The farther you are from an object, the weaker its gravity. So if you have a long object near a massive one, the long object will feel a stronger gravitational force on the near end versus a weaker force on the far end! This change in gravity over distance is called the tidal force (which is a bit of a misnomer, it’s not really a force, it’s a differential force, and yes, it’s related to why we have ocean tides on Earth from the Moon).

The thing is, black holes can be small - a BH with a mass of about three times the Sun has an event horizon just a few kilometers across - and that means you can get close to them. And that in turn means that the tidal force you feel from one can get distressingly big.

Let’s say you fall feet first into a stellar-mass BH. It turns out that as you approach, the difference in gravity between your head and your feet can get huge. HUGE. The force can be so strong that your feet get yanked away from your head with hundreds of millions of times the force of Earth’s gravity. You’d be stretched into a long, thin strand and then shredded.

Astronomers call this spaghettification. Ewwww.

So getting near a black hole is dangerous even if you don’t fall in. Evidently, there really is a tide in the affairs of men.

7) Black holes aren’t always dark

The thing is, black holes can kill from a long way off.

Matter falling into a black hole would rarely if ever just fall straight in and disappear. If it has a little bit of sideways motion it’ll go around the black hole. As more matter falls in, all this junk can pile up around the hole. Because of the way rotating objects behave, this matter will create a disk of material whirling madly around the hole, and because the gravity of the hole changes so rapidly with distance, matter close in will be orbiting much faster than stuff farther out. This matter literally rubs together, generating heat through friction. This stuff can get really hot, like millions of degrees hot. Matter that hot glows with intense brightness… which means that near the black hole, this matter can be seriously luminous.

Worse, magnetic and other forces can focus two beams of energy that go plowing out of the poles of the disk. The beams start just outside the black hole, but can be seen for millions or even billions of light years distant.

They’re bright.

In fact, black holes that are eating matter in this way can glow so brightly that they become the brightest continuously-emitting objects in the Universe! We call these active black holes.

And as if black holes aren’t dangerous enough, the matter gets so hot right before it makes the final plunge that it can furiously emit X-rays, high-energy forms of light (and the beams can emit even higher energy light than that). So even if you park your spaceship well outside the event horizon of a black hole, if something else falls in and gets shredded, you get rewarded by being fried by the equivalent of a gazillion dental exams.

Black holes are dangerous. Best to stay away from them.

8) Black holes aren’t always dangerous.

Having said that, let me ask you a question: if I were to take the Sun and replace it with Folgers crystals a black hole of the exact same mass, what would happen? Would the Earth fall in, be flung away, or just orbit like it always does?

Most people think the Earth would fall in, sucked inexorably down by the black hole’s powerful gravity. But remember, the gravity you feel from an object depends on the mass of the object and your distance from it. I said the black hole has the same mass as the Sun, remember? And the Earth’s distance hasn’t changed. So the gravity we’d feel from here, 150 million kilometers away, would be exactly the same! So the Earth would orbit the solar black hole just as nicely as it orbits the Sun now.

Of course, we’d freeze to death. You can’t have everything.

9) Black holes can get big.

Q: What happens if two stellar-mass black holes collide?

A: You get one bigger black hole.

You can extrapolate from there. Black holes can eat other objects, including other black holes, so they can grow. We think that early on in the Universe, when galaxies were just forming, matter collecting in the center of the nascent galaxy can collapse to form a very massive black hole. As more matter falls in, the hole greedily consumes it, and grows. Eventually you get a supermassive black hole, one with millions or even billions of times the mass of the Sun.

However, remember that as matter falls in it can get hot. It can be so hot that the pressure from light itself can blow off material that’s farther out, a bit like the solar wind but on a much grander scale. The strength of the wind depends on many things, including the mass of the black hole; the heftier the hole, the windier the, uh, wind. This wind prevents more matter from falling in, so it acts like a cutoff valve for the ever-increasingly girthy hole.

Not only that, but over time the gas and dust around the black hole (well, pretty far out, but still near the center of the galaxy) gets turned into stars. Gas can fall into a black hole more easily than stars (if gas clouds collide head-on their motion relative to the black hole can stop, allowing them to fall in; stars are too small and too far apart for this to happen). So eventually the black hole stops consuming matter because nothing more is falling into it. It stops growing, the galaxy becomes stable, and everyone is happy.

In fact, when we look into the Universe today, we see that pretty much every large galaxy has a supermassive black hole in its heart. Even the Milky Way has a black hole at its core with a mass of four millions times that of the Sun. Before you start running around in circles and screaming, remember this: 1) it’s a long way off, 26,000 light years (260 quadrillion kilometers), 2) its mass is still very small compared to the 200 billion solar masses of our galaxy, and therefore 3) it can’t really harm us. Unless it starts actively feeding. Which it isn’t. But it might start sometime, if something falls into it. Though we don’t know of anything that can fall into it soon. But we might miss cold gas.

Anyway, remember this as well: even though black holes can cause death and destruction on a major scale, they also help galaxies themselves form! So we owe our existence to them.

10) Black holes can be low density.

Of all the weirdnesses about black holes, this one is the weirdest to me.

As you might expect, the event horizon of a black hole gets bigger as the mass gets bigger. That’s because if you add mass, the gravity gets stronger, which means the event horizon will grow.

If you do the math carefully, you find that the event horizon grows linearly with the mass. In other words, if you double the black hole’s mass, the event horizon radius doubles as well.

That’s weird! Why?

The volume of a sphere depends on the cube of the radius (think way back to high school: volume = 4/3 x ? x radius3). Double the radius, and the volume goes up by 2 x 2 x 2 = 8 times. Make the radius of a sphere 10 times bigger and the volume goes up by a factor of 10 x 10 x 10 = 1000.

So volume goes up really quickly as you increase the size of a sphere.

Now imagine you have two spheres of clay that are the same size. Lump them together. Is the resulting sphere twice as big?

No! You’ve doubled the mass, but the radius only increases a little bit. Because volume goes as radius cubed, to double the radius of your final clay ball, you’d need to lump together eight of them.

But that’s different than a black hole. Double the mass, double the size of the event horizon. That has an odd implication…

Density is how much mass is packed into a given volume. Keep the size the same and add mass, and the density goes up. Increase the volume, but keep the mass the same, and the density goes down. Got it?

So now let’s look at the average density of matter inside the event horizon of the black hole. If I take two identical black holes and collide them, the event horizon size doubles, and the mass doubles too. But volume has gone up by eight times! So the density actually decreases, and is 1/4 what I started with (twice the mass and eight times the volume gives you 1/4 the density). Keep doing that, and the density decreases.

A regular black hole - that is, one with three times the Sun’s mass - with have an event horizon radius of about 9 km. That means it has a huge density, about two quadrillion grams per cubic cm (2 x 1015). But double the mass, and the density drops by a factor of four. Put in 10 times the mass and the density drops by a factor of 100. A billion solar mass black hole (big, but we see them this big in galaxy centers) would drop that density by a factor of 1 x 1018. That would give it a density of roughly 1/1000 of a gram per cc… and that’s the density of air!

A billion solar mass black hole would have an event horizon 3 billion km in radius - roughly the distance of Neptune to the Sun.