Wednesday, June 17, 2009

Look – Up in the Sky!

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Look – Up in the Sky!

When television was young, there was a hugely popular show based on the still popular fictional character of Superman. The opening of that show had a familiar phrase that went, “Look. Up in the sky. It’s a bird. It’s a plane. It’s Superman!” How beloved Superman has become in our culture and the worldwide fascination with extraterrestrials and all things cosmic only emphasizes that there is a deep curiosity in all humans about nature and astronomy, even if many people would not know to call it astronomy.

Astronomy is one of the oldest sciences of all time. When archeologists unearth ancient civilizations, even as far back as the cavemen, they invariably find art that shows mans unquenchable fascination with the stars. To this day, you can easily get an animated discussion at any gathering on the topic of “Is there intelligent life on other planets?”

Many have tried to explain mankind’s seeming obsession with outer space as a result of an ancient memory or as part of mankind’s eternal nature. Whatever the cause, people of every age and every nation share this one deep interest, to know more about the universe that our tiny planet is just a part of.

It’s rather strange because the actual conduct of a serious student of astronomy is really not the stuff of high adventure. You will never see a “Raiders of the Lost Arc” or “Jurassic Park” movie made about an astronomer. Excitement for lovers of this science is to stay up all night watching the cosmos through a powerful telescope. But that fact does not seem to discourage the tens of thousands to get into astronomy each year and the huge interest worldwide with the stars, the planets and the universe.

There may be no other universal human fascination that does so much to make national boundaries and even international animosity seem to evaporate. Other than the Olympic movement, international cooperation to achieve great strides for human kind in space seems to go forward without interruption even when the nations cooperating in those projects are virtually at war back on the surface of the earth. It is a strange thing to watch as Russian, American and other astronauts work together like brothers on space missions even as their home nations are busily pointing missiles at each other back at home. It almost makes you think that we should put more energy and money into the space program, not less because it seems to be a bond that heals tension rather than creates it.

Why is astronomy so exciting even though we have no dinosaurs, moving animals or any real danger to most who are obsessed with the discipline? It may go back to a basic curiosity that all human beings have about their natural habitat and this big mysterious thing out there called space. Maybe it goes back to that old saying at the beginning of Star Trek that space is “the final frontier”.

But we all share that ongoing sense of excitement each time we take out our telescopes and gaze directly at the cosmos above us. We feel we are looking at the very dawn of time. And in light of the issues with the speed of light which means that many of the twinkling stars out there are really light from those stars that started their journey to us thousands of years ago, we are in actually looking directly at the past every time we direct our eyes skyward.

But we don’t have to worry about ever conquering the final frontier and finding our curiosity satisfied. There will always be more to learn and discover in the world of astronomy. And it is likely that mankind’s curiosity about astronomy is just as limitless as well.

Moon Fever

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.

Moon Gazing

For many of us, our very first experience of learning about the celestial bodies begins when we saw our first full moon in the sky. It is truly a magnificent view even to the naked eye. If the night is clear, you can see amazing detail of the lunar surface just star gazing on in your back yard.

Naturally, as you grow in your love of astronomy, you will find many celestial bodies fascinating. But the moon may always be our first love because is the one far away space object that has the unique distinction of flying close to the earth and upon which man has walked.

Your study of the moon, like anything else, can go from the simple to the very complex. To gaze at the moon with the naked eye, making yourself familiar with the lunar map will help you pick out the seas, craters and other geographic phenomenon that others have already mapped to make your study more enjoyable. Moon maps can be had from any astronomy shop or online and they are well worth the investment.

The best time to view the moon, obviously, is at night when there are few clouds and the weather is accommodating for a long and lasting study. The first quarter yields the greatest detail of study. And don’t be fooled but the blotting out of part of the moon when it is not in full moon stage. The phenomenon known as “earthshine” gives you the ability to see the darkened part of the moon with some detail as well, even if the moon is only at quarter or half display.

To kick it up a notch, a good pair of binoculars can do wonders for the detail you will see on the lunar surface. For best results, get a good wide field in the binocular settings so you can take in the lunar landscape in all its beauty. And because it is almost impossible to hold the binoculars still for the length of time you will want to gaze at this magnificent body in space, you may want to add to your equipment arsenal a good tripod that you can affix the binoculars to so you can study the moon in comfort and with a stable viewing platform.

Of course, to take your moon worship to the ultimate, stepping your equipment up to a good starter telescope will give you the most stunning detail of the lunar surface. With each of these upgrades your knowledge and the depth and scope of what you will be able to see will improve geometrically. For many amateur astronomers, we sometimes cannot get enough of what we can see on this our closest space object.

To take it to a natural next level, you may want to take advantage of partnerships with other astronomers or by visiting one of the truly great telescopes that have been set up by professionals who have invested in better techniques for eliminating atmospheric interference to see the moon even better. The internet can give you access to the Hubble and many of the huge telescopes that are pointed at the moon all the time. Further, many astronomy clubs are working on ways to combine multiple telescopes, carefully synchronized with computers for the best view of the lunar landscape.

Becoming part of the society of devoted amateur astronomers will give you access to these organized efforts to reach new levels in our ability to study the Earth’s moon. And it will give you peers and friends who share your passion for astronomy and who can share their experience and areas of expertise as you seek to find where you might look next in the huge night sky, at the moon and beyond it in your quest for knowledge about the seemingly endless universe above us.

Our Neighbors in Space

We have a special feeling toward the other planets that circle our sun. Maybe it’s all the science fiction stories about visiting the moon, Mars and other planets. But we love to think about those planets that make up what we call “the solar system.” that do what our planet does but do it very differently indeed.

The planets of our solar system have taken on personalities and mythical appeal in our literature and arts. It is easy to find artists who render their vision of the planets that make up our society of planets near our sun. The names of the planets, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune are all from our cultural past being gods from Greek and Roman mythology. But the solar system is not just made up of these planets. The solar system is a very busy place indeed.

In 2006, there was quite a bit of controversy as scholars and astronomers agreed to downgrade Pluto and remove its status as a planet. So you have to wonder, what is it that makes something a planet and what happened to Pluto? It didn’t just go away so it must still be out there. A planet, by scientific definition is any object in orbit around a sun, that has formed into some kind of round object is a planet as long as it has cleared away any other orbiting items around it. By cleared away, that doesn’t mean it has destroyed all space debris etc. For example, our planet has not “cleared away” the moon but it has captured it into its own orbit so we classify as a planet. That’s a relief huh?

There are many objects floating around in our solar system other than the planets we know of. It’s an interesting piece of trivia that in addition to the planets there are 165 moons orbiting around those nine planets. Some of those moons are so advanced that some scientists have suspected that they might have supported life at some point.

In addition to the regular planets and moons, there are dwarf planets, asteroid belts and routine visits by comets that create a lot of traffic in our cosmic corner of the universe. The two known dwarf planets that exist on the outer rim of our solar system are Eries and Ceres. So when Pluto’s status was changed to be removed from the list of planets, it simply joined those two bodies as dwarf planets but still a solid citizen of the community of celestial bodies around our sun.

In addition to these larger bodies, there is an asteroid belt that exists between Mars and Jupiter that most of the asteroids that we see in our night sky come from. There is another belt of large objects further out called the Kuiper belt as well as a “bubble” in space called a heliopause and there is a suspected additional belt outside the known solar system called the Oort belt that we think is the origin of a lot of large asteroids and comets that frequent our solar system and come to orbit our sun.

As fascinating as these many celestial bodies who are our neighbors in space is the origin of our solar system. We have to break it down to simple terms to understand the terms but we know that the early history of the solar system and the universe was one of great bodies of gas and clouds of matter eventually cooling and heating, exploding and spinning off stars and other massive space giants that became more stars, galaxies and solar systems. It was from this erratic activity that our sun separated from the gasses and carried with it the material that became our solar system. The gravity of the sun captured sufficient matter that it began to go through the process of forming, cooling, exploding and separating. This is what happened as the planets all went through he same process eventually establishing stable orbits and small objects falling into orbit around them.

When you think of how powerful and out of control this process is, it’s amazing to step back and see the beauty of the organization of our solar system today. The more detail you learn about the history of our solar system, the more you will enjoy your explorations of the planets with your telescope. That that discovery is part of the fun of astronomy.

Pictures in the Sky

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.

Radio Astronomy

For most of us, the idea of astronomy is something we directly connect to “stargazing”, telescopes and seeing magnificent displays in the heavens. And to be sure, that is the exciting area of astronomy that accounts for it’s huge popularity. So to the uninitiated, the idea of “radio astronomy” seems strange. There are two reasons for that. First is that humans are far more visual than audio oriented. And the second is that radio astronomy doesn’t really involve “listening” to the cosmos except to the extent that scientists who use this sophisticated form of “stargazing” do not rely on visual study to conduct their work.

To appreciate what is really exciting about radio astronomy, first we have to shift how we view astronomy. That is because to professional astronomers, studying the universe is more about frequencies than it is about visual documentation of phenomenon. This takes us back to Physics 101.

Light, obviously, is the physical phenomenon that empowers our ability to use our visual confirmation system, e.g. our eyes to appreciate something, in this case the stars. So when we look up at the heavens, we can see the light emitting from a star or reflecting from a planet or moon. In many cases, if we see a far away star, we are actually seeing it hundreds or thousands of years ago because that is how long it takes for that light to cross the universe and be visible in our sky. That alone is a pretty mind blowing idea.

Now light itself is a pretty strange substance. But to our astronomy scientists, light is just another energy that exists in a certain frequency. Now, we tend to think of frequencies when we talk about sound waves. In scientific terms light, energy and sound are just a few forms of the same thing, frequencies of energy that are emulating from a source.

Now we get to why radio astronomy is so necessary. The range of frequency that light occupies in the big spectrum of frequencies is really pretty small. To put that more bluntly, we can only “see” a tiny part of the universe that is actually there. Now when you look up in the night sky and it is so overwhelming, when you then that we are seeing just a tiny amount of what is actually going on up there, again, our minds can get pretty overwhelmed.

Radio astronomy uses sophisticated sensor equipment to study ALL of the frequencies of energy coming to us from the cosmos. In that way, these scientists can “see” everything that is going on out there and so get a precise idea of how the stars look, behave now and will behave in the future.

For some of us who have heard about radio astronomy, we think of it in terms of “listening” for signs of life in the universe. And yes, SETI, or “the Search for Extra Terrestrial Intelligence” is a part of radio astronomy, albeit a tiny part. But of much greater importance is how radio astronomy has empowered serious astronomers (that is those who get paid to do it) to study stars many light years away, to study black holes which we could never see with our telescopes and to gather research and data about the whole of the universe that otherwise would be impossible to know and understand.

This is important work that is constantly ongoing in the world of astronomy. It is worth keeping up with and learning more about as we have barely scratched the surface in our brief discussion today. But understanding how important radio astronomy is will only deepen and make more meaningful your love and grasp of this big field of knowledge known as astronomy.



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