Monday, June 28, 2010

Astronomy for Kids - Instill the Nature Loving

There is something about parenthood that gives us a sense of history and a deeply rooted desire to send on into the next generation the great things we have discovered about life. And part of that is the desire to instill in our children the love of science, of learning and particularly the love of nature.

Your fascination with the universe and how to explore it as we so often do in the field of astronomy can be highly academic and dry as maybe it was if you took a course in astronomy. But when you get out there in the field at night, your equipment is just right and the night sky comes alive with activity, there is no other experience like it for majesty and pure excitement. And that is the kind of experience we want our children to come to love as much as we do.

It’s actually not a big jump from play to learning for children when it comes to learning about the natural world, science and astronomy. Exploration is a natural part of being a child and growing up in a fascinating world and universe. So if we can find ways to take that natural desire to explore and instill a life long passion for astronomy, we will have given our children a truly great gift.

So with a few simple family activities, we can instill that love of astronomy in our offspring. Here are some ideas.

* Make star gazing part of family life. You already love to go outdoors as often as possible to enjoy the stars. So don’t let that be your private passion. Get everybody into the act. The kids will love it and look forward to those nights as much as going to the circus.

* Make each new experience in growing into astronomy a fresh threshold. So the first experiences might be what you experienced as a kid, just laying on your back out in the country with the panorama of the stars overhead trying to take it all in. Go ahead and challenge them to count the stars. It’s a fun exercise and one they will save to use as a joke on their kids when they do this same thing in a few decades.

* Take them along the road of learning, introducing binoculars so they can focus on particular areas of the night sky.

* Now they are hooked and want to know about why some of the stars are brighter than others. They have no idea they are going to astronomy school and don’t even know it. You can tell them about the constellations as you point out how to find them by keying off the North Star. By being able to find things in that mass of stars and knowing there is such a vast amount more they can pick out, they are ripe for learning from star maps and about how the galaxies work.

* Think of their excitement as they notice the changes in the night sky. The phases of the moon and the effect of the rotation of the earth on the position of the planets. Help them find their favorite celestial bodies each night. Before long they will learn to chart the movement of the stars just like the early astronomers did.

* Now you will get caught up in the excitement of finding new things to reveal to your excited crew of fledgling astronomers. When you reveal that you are going on a safari to see an eclipse, a meteor shower or the once in a lifetime appearance of a comet, that gift will as big as anything you might spring on them for Christmas.

The wonders of the night sky will captivate your children the way it has you for years. And you will have done them the greatest favor you ever could do by making them lifelong lovers of the universe.

Friday, June 25, 2010

Studying the Night Sky

No matter how far along you are in your sophistication as an amateur astronomer, there is always one fundamental moment that we all go back to. That is that very first moment that we went out where you could really see the cosmos well and you took in the night sky. For city dwellers, this is a revelation as profound as if we discovered aliens living among us. Most of us have no idea the vast panorama of lights that dot a clear night sky when there are no city lights to interfere with the view.

Sure we all love the enhanced experience of studying the sky using binoculars and various sizes and powers of telescopes. But I bet you can remember as a child that very first time you saw the fully displayed clear night sky with all the amazing constellations, meters and comets moving about and an exposure of dots of light far to numerous to ever count.

The best way to recapture the wonder of that moment is to go out in the country with a child of your own or one who has never had this experience and be there at that moment when they gaze up and say that very powerful word that is the only one that can summarize the feelings they are having viewing that magnificent sky. That word is – “Wow”.

Probably the most phenomenal fact about what that child is looking at that is also the thing that is most difficult for them to grasp is the sheer enormity of what is above them and what it represents. The very fact that almost certainly, virtually every dot up there in the sky is another star or celestial body that is vastly larger that Earth itself, not by twice or ten times but by factors of hundreds and thousands, can be a mind blowing idea to kids. Children have enough trouble imagining the size of earth itself, much less something on such a grand scope as outer space.

But when it comes to astronomy, we do better when we fall into deeper and deeper levels of awe at what we see up there in the night sky. Some amazing facts about what the children are looking at can add to the goose bumps they are already having as they gaze eyes skyward. Facts like…

* Our sun is part of a huge galaxy called the Milky Way that consists of one hundred billion stars just like it or larger. Show them that one hundred billion is 100,000,000,000 and you will se some jaws drop for sure.

* The milky was is just one of tens of billions of galaxies each of which has billions of stars in them as well. In fact, the Milky Way is one of the small galaxies.

* If you wanted to drive across the Milky Way, it would take you 100,000 years. But you can’t get there driving the speed limit. You have to drive five trillion, eight hundred million miles per year to get all the way across that fast.

* Scientists calculate that the Milky Way is 14 billion years old.

These little fun facts should get a pretty spirited discussion going about the origins of the universe and about the possibility of space travel or if there are life on other planets. You can challenge the kids to calculate that if every star in the Milky Way supported nine planets and if only one of them was habitable like earth is, what are the odds that life would exist on one of them? I think you will see some genuine excitement when they try to run those numbers.

Such discussion can be fun, exciting, and full of questions. Don’t be too hasty to shut down their imaginations as this is the birth of a lifelong love of astronomy that they are experiencing. And if you were there that first moment when they saw that night sky, you will re-experience your own great moment when you was a child. And it might set off a whole new excitement about astronomy in you all over again.

Wednesday, June 23, 2010

The History of Astronomy

If you have a passion for star gazing, telescopes, the Hubble and the universe and this thing we call “astronomy”, you are far from alone. Of course, we know that astronomy is a highly respected science that has produced some of the most amazing accomplishments of the twentieth century. On top of that, it is a thriving area of fascination and one of the most exciting hobby areas going with thousands of astronomy clubs and tens of thousands of amateur astronomers watching the stars every night just like we do.

But did you know that astronomy is one of the oldest and most respected sciences of them all? As far back as before the times of Christ, the wise and thinking people of societies of the time were looking at the stars and finding ways to track and chart them. We who love the hobby of astronomy can chart a proud history of astronomers that tracks across millennia and through virtually every culture in civilization. So for the sake of having some really good trivia to toss around at astronomy club next week, let’s highlight some of the big moments in the history of astronomy.

For many centuries the science of astronomy was not distinct from the practice of astrology. For clarity, astronomy is the study of the stars, planets, and the universe with a clearly scientific approach. Astrology is the study of the zodiac signs and how they influence our growth, our personalities and our daily lives. In modern times, we as people of science discount the astrological side and focus on the astronomy of the heavens. But they were one study for millennia before the age of science made them separate.

There is historical evidence that astronomy was a recognized science as far back as the Babylonian civilization hundreds of years before Christ. But the study of the stars was not limited to one country. There were similar movements going on in China, India, and Ancient Egypt and all over the Arabian Peninsula. The integration of astronomy and religion is so prevalent that we see it in the Christmas story in which the Magi, Zoroastrian priesthood probably from the equivalent of ancient Syria, followed a star to the Christ child. These astronomers were also astrologers and it was that mixture that lead them to be part of this historic event.

The first book on astronomy was written by Ptolemy during the Greek empire. Since that historic publication, the who’s who list of great astronomers charts a path right through the center of modern science including Copernicus, Galileo, Kepler, Sir Issac Newton, Jung, Michelangelo, Benjamin Franklin and more recently even Einstein and Stephen Hawkings would join that noble list. It seemed that from the renaissance on to this day, virtually any man or woman of intellect dabbled in astronomy at least somewhat and it has always been considered a sign of the learned to know about the universe and things astronomical.

Astronomy has had an impact on so many areas of our lives that we really don’t recognize. Many words in our language had their roots in astronomy such as…

* Influenza which comes from the Latin root word for influence. This reflects an early belief that the position of the moon and stars may influence health and cause or cure disease.

* Disaster which comes from the Latin for “bad star”.

* Lunatic which has the root word "Luna" in it which is the Latin word for moon. This highlights the long held belief that is even prevalent today that irrational behavior and even wild and dangerous things happen during a full moon.

Astronomy and its interrelationship with astrology has also influenced culture, education and religion to a very large extent over the centuries. In the English language, the first two days or our week, Sunday and Monday are a reference to astronomy as their literal interpretations would be “The Day of the Sun” and “The Day of the Moon.”

So if you have found astronomy becoming a consuming passion in your thoughts and what fascinates you about the world we live in, you are in great company as this area of study has been a major part of culture and thought virtually since the dawn of civilization. And it will continue to fascinate mankind for as long as those beautiful stars shine over our heads.

Sunday, June 20, 2010

The Glossary of Telescopes

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.

Thursday, June 17, 2010

The Basics of Buying a Telescope

There is a moment in the life of any aspiring astronomer that it is time to buy that first telescope. It’s exciting to think about setting up your own viewing station whether that is on the deck of your home or having a powerful but mobile telescope set up to take to the remove countryside to really get a good shot at some breath taking star gazing.

The last thing we would want to do is to take away any of the “fun” of your hobby of astronomy because the joy of what we do as star gazers is a big part of the appeal. But unlike many other hobbies, ours is a passion of science, of learning and of discovery. And don’t kid yourself, even a hobbyist with a limited telescopic set up can see some amazing things in the stars. So let’s be sure you invest in a solid piece of equipment that you can continue to grow with as your knowledge and ability as an astronomer grows. But how do we do that?

Meet the Geeks.

Now we use the term “telescope geeks” lovingly because any of us who are devoted to our love of astronomy eventually become telescope geeks. And these are the type of people who will know exactly how to evaluate your needs in terms of where you are right now and where you want to go as your hobby grows with you. So if you have not yet associated with a local astronomy club, now is the time to do it.

Start rubbing elbows with people who live and breathe telescopes. Their input is a hundred times more reliable than what a sales brochure or that salesman might have to say because the “telescope geeks” have been where you are, made the mistakes and are eager to help you avoid those same mistakes.

Size Matters

In the world of telescopes, the sales people see, to try to baffle us with all the bells and whistles of their hottest selling model. One of the big check points that is often pushed is the amplification level of the telescope lens. While that is a factor that is worth noting, when it comes to a telescope lens, the old phrase “size matters” is a good guideline.

Just remember that your telescope lens works best when it takes in the most light it can from the object you are viewing. So the wider the diameter of the lens, the better a view you are going to get. So don’t fall for the amplification level only. Carefully evaluate the lens size so you have the right fit for what you want to do.

It Has to Stand on Its Own Feet.

If you are going to set up a permanent telescope station, then you can bolt the unit down so it is well supported. But many of us have to take our telescopes out into the country for optimum use. So the stand has to be strong and flexible so we can set up the telescope on uneven turf but still feel secure that this important and expensive piece of equipment is going to stand on its own without fear of it falling during our observation time.

We already mentioned strong and flexible as evaluation guides for the telescope stand but add in ease of use as well. You have to be able to set your telescope up and break it down quickly and easily when you are on a remote viewing. You may even find yourself setting up or taking down your telescope in the dark or by lantern or flashlight if you are taking advantage of the great star displays in the late night sky that make this hobby so exciting.

These are the basics of what to look for in your new telescope. Finally, make sure the telescope can be enhanced and expanded without having to throw the first unit away and buy something completely new. You want your telescope to grow as your knowledge and skills grow. If your first telescope meets all of these requirements, you are off on the right foot on a long and enjoyable career as an amateur astronomer.

Tuesday, June 15, 2010

The Amazing Hubble

In the history of modern astronomy, there is probably no one greater leap forward than the building and launch of the space telescope known as the Hubble. While NASA has had many ups and downs, the launch and continued operation of the Hubble space telescope probably ranks next to the moon landings and the development of the Space Shuttle as one of the greatest space exploration accomplishments of the last hundred years.

An amazing piece of astronomy trivia that few people know is that in truth, only about ten percent of the universe is visible using conventional methods of observation. For that reason, the Hubble really was a huge leap forward. That is for the very simple reason that the Hubble can operate outside of the atmosphere of Earth. Trying to make significant space exploration via telescopes from the terrestrial surface of planet Earth is very difficult. That very thing that keeps us alive, our own Earth’s atmosphere presents a serious distraction from being able to see deeper and further into space.

The Hubble space telescope was named after the great scientist and visionary Edward Hubble who discovered that the universe was expanding which was explained by what is now known in science as Hubble’s Law. To truly get a feel for the amazing accomplishment that was achieved with the launch of the Hubble telescope, spend some time on Nasa’s web site dedicated to the project at http://hubble.nasa.gov. There are also a number of sites where you can enjoy some stunning pictures from the Hubble including http://heritage.stsci.edu/ and http://www.stsci.edu/ftp/science/hdf/hdf.html.

It’s hard to believe how long the Hubble has been orbiting earth and sending back amazing video and pictures of what it is discovering in space. But the Hubble was actually initially launched on April 25th 1990. It was the culmination of literally decades of research and construction which began in 1977. Expectations were high as the orbiting telescope was put in place and actually began to function as it was designed to do.

All was not always perfect with the telescope and the early pictures were disappointing. After some study NASA discovered that the reason for the early failures was the curvatures of one of the main lenses of the orbiting telescope.

We probably could never have kept this intricate piece of equipment operational as well as we have had we not had the Space Shuttle program to give us a tool to implement repairs and improvements to the Hubble. In 1993 a new lens was installed on the Hubble which corrected the problem of picture resolution that was noted in the early operation of the telescope.

Two other repair and upgrade mission have been made to the Hubble since it launched, both of them in 1997 to upgrade older equipment and to retrofit the telescope to extend its useful life through 2010. It’s pretty amazing to think that this scientific and mechanical marvel has been operating now for ten years without maintenance. We can be assured that plans are in the works for NASA to upgrade or replace parts on the Hubble to extend its useful life even further as that 2010 time frame draws closer.

It is hard to imagine the science of astronomy or the natural quest for greater knowledge of our universe without the Hubble. While many times those who would not fund space exploration have tried to cut funding for the Hubble, the operation of this telescope is just too important to astronomers and to the scientific well being of mankind and our planet not to continue to use the Hubble, or its next natural successor. We will always need to have a set of eyes in the sky to watch the universe and discover more of its mysteries.

Saturday, June 12, 2010

Astronomy Telescopes - A Buying Guide

Buying the right telescope to take your love of astronomy to the next level is a big next step in the development of your passion for the stars. In many ways, it is a big step from someone who is just fooling around with astronomy to a serious student of the science. But you and I both know that there is still another big step after buying a telescope before you really know how to use it.

So it is critically important that you get just the right telescope for where you are and what your star gazing preferences are. To start with, let’s discuss the three major kinds of telescopes and then lay down some “Telescope 101” concepts to increase your chances that you will buy the right thing.

The three primary types of telescopes that the amateur astronomer might buy are the Refractor, the Reflector and the Schmidt Cassegrain telescope. The first two are named for the kind of lens that is used. It is pretty easy to see that the lens is the heart of the telescope so the kind that you will use will determine the success of your use of that telescope.

The refractor lens is the simplest because it uses a convex lens to focus the light on the eyepiece. So the lens bends outwards for this purpose. The refractor telescope’s strength is in viewing planets. The reflector’s strength is in seeing more distant objects and the lens is concave or bends in. It uses mirrors to focus the image that you eventually see. The final type, the Schmidt Cassegrain telescope is the most complex and accomplishes the goals of both but it uses an involved system of mirrors to capture the image you want to see.

So to select just the right kind of telescope, your objectives in using the telescope are important. To really understand the strengths and weaknesses not only of the lenses and telescope design but also in how the telescope performs in various star gazing situations, it is best to do some homework up front and get exposure to the different kinds. So before you make your first purchase…

* Above all, establish a relationship with a reputable telescope shop that employs people who know their stuff. If you buy your telescope at a Wal-Mart or department store, the odds you will get the right thing are remote.

* Pick the brains of the experts. If you are not already active in an astronomy society or club, the sales people at the telescope store will be able to guide you to the active societies in your area. Once you have connections with people who have bought telescopes, you can get advice about what works and what to avoid that is more valid than anything you will get from a web article or a salesperson at Wal-Mart.

* Try before you buy. This is another advantage of going on some field trips with the astronomy club. You can set aside some quality hours with people who know telescopes and have their rigs set up to examine their equipment, learn the key technical aspects, and try them out before you sink money in your own set up.

There are other considerations to factor into your final purchase decision. How mobile must your telescope be? The tripod or other accessory decisions will change significantly with a telescope that will live on your deck versus one that you plan to take to many remote locations. Along those lines, how difficult is the set up and break down? How complex is the telescope and will you have trouble with maintenance? Network to get the answers to these and other questions. If you do your homework like this, you will find just the right telescope for this next big step in the evolution of your passion for astronomy.

This post was made using the Auto Blogging Software from WebMagnates.org This line will not appear when posts are made after activating the software to full version.

Wednesday, June 9, 2010

Space, The Final Frontier

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.

Monday, June 7, 2010

Shooting Stars - Strange Light in the Sky

If you are a serious astronomy fanatic like a lot of us are, you can probably remember that one event in childhood that started you along this exciting hobby. It might have been that first time you looked through a telescope. But for many of us, it was that first time we saw a rain of fire from the sky that we eventually came to know as a meteoroid shower.

At the time when you see the first one, it’s easy to remember the movie “war of the worlds” or some other fantastic image of aliens entering our atmosphere in droves to take over the planet. But with some guidance and explanation of what was going on, we eventually learned that these showers were not at all threatening or any kind of invasion. For the most part meteoroid showers are harmless, part of nature and very fun to watch.

So what are these strange lights in the sky? Are they aliens invading from Mars? Are the comets coming to start the next ice age? Or perhaps asteroids burning up as they enter the earths atmosphere. The answer to the above questions is no to the first and “yes and no” to the other two.

A meteoroid is actually a small piece of space rubble, usually dust or small rocks that come from either a comet or the break up of an asteroid in space and that eventually plummets toward the earth. We say “toward the earth” because the lights you see are the friction of the atmosphere burning up those small space tidbits and creating a spectacular show for all of us as they do so. A particularly exciting moment to witness is when a meteoroid breaks up or explodes on entry. A meteoroid that explodes is called bolides.

There are some interesting details about the life of a meteoroid that make the viewing of shooting stars even more fun. To be seen, a meteoroid only needs to weigh as little as a millionth of a gram. But the thing that makes them so spectacular to see is the tremendous speeds they reach as they enter the atmosphere. Before burning up, a meteoroid will reach between 11 and 74 kilometers per second which is 100 times faster than a speeding bullet.

We tend to think of t seeing a shooting star as a freak event and we associate it with superstition (hence, wish on a lucky star). But there are actually thousands of them every year so it really isn’t that rare to see one. In fact, scientists tell us that over 200,000 tons of space matter enters the atmosphere each year and burns up on entry.

Comets are a big source of meteoroids because of the nature of those long tails. A large amount of dust, ice and other space debris gets caught up in a comet’s tail as it moves toward the sun. Then as the comet moves away from the sun in its orbit, tons of this matter is thrown off into space to disperse. As the Earth moves in its routine orbit around the sun, it often crosses through clouds of this discarded matter which becomes one of those “meteor showers” that are so popular for viewing.

These showers of shooting stars are pretty easy for astronomers to predict so you can get into position to see the excitement at just the right time of night and be looking at the right area of the night sky. Usually the astronomy magazine or site will give you a general time and location to be ready to look when the meteoroids start to fall.

Now keep in mind, this is a phenomenon of nature, so it may not observe the time table exactly. Also note that there is a notation system for where the meteoroid shower will occur based on what constellation is its backdrop. The section of the sky to focus on for the show is called the “radiant” because that is where the entering meteoroids begin to glow or radiate. The radiant is named for the constellation it is nearest too. So if the meteor shower is going to occur in the constellation of Leo, then its radiant will be called Leonid. This will help you decipher the listing of asteroid showers in the publications.

Friday, June 4, 2010

Radio Astronomy 101

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.

Tuesday, June 1, 2010

Astronomy - The Natural 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.