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The Skies Above Holiday Gift Guide

Observing >

If local stores haven't reminded you already with their early displays of nativity scenes and lights and snowmen, we are fast approaching the major gift-giving time of the year. My motives here for reminding you of this are slightly purer than the chain stores'; I am asking you to consider giving gifts this year which will get people excited about the beauties of the cosmos. And now is the time to start considering it.

There are all kinds of possible gifts to ponder. Let's start with the most obvious --- telescopes.

Please, please, please do not even consider giving someone a cheap department store telescope. The scope whose primary brag line spouts "Magnifies thousands of times!" is the very one to avoid. Too often those store models are poorly made, plastic-lensed rubbish that can better be used for unclogging toilets. Their horrible optics leave the new user utterly frustrated and quickly turned off to the heavens.

One of the most important characteristics of a good scope is how much light it can gather. So try and get the biggest mirror or lens size you can reasonably afford. The mirror type of scope, called a reflector (as opposed to the lensed one, called a refractor) is usually the less expensive of the two.

There are several other things you should consider and several websites can give you detailed and easily understood hints from the experts. Go see telescope.com, astronomy.com, and skypub.com.

And don't forget binoculars! They are more limited than scopes, of course, but they are less expensive and can still provide beautiful wide-angled views of the heavens.

If you are buying for someone who has a scope or binoculars already, despair not! There are all sorts of cool gadgets and accessories for scopes --- special eyepieces and filters and lights and chairs and… you get the idea. You can find these items via those websites and at telescope stores.

Some local stores that can help you out in your endeavor include Oceanside Photo and Telescope and San Diego's Scope City. They can expertly help you choose scopes and accessories to your heart's delight.

Does your gift getter like computers? There are absolutely stunning programs you can buy which turn your computer into a virtual universe. These apps allow you to travel through the galaxy, visit other planets, and see the whole shebang animated with striking accuracy and visual effects. The one I personally use for teaching and in writing this column is Starry Night. It is for both Mac and PC, and is available in different levels of expertise --- e.g. Starry Night Enthusiast or Starry Night Pro. See space.com for details. But shop around for other programs and see what suits your fancy.

And of course, there are books --- all kinds of astronomy books --- and any good bookstore should be full of them. There are books on the history of astronomy, the history of the universe, famous astronomers, how to take digital images of heavenly bodies, and all-encompassing college textbooks. And there are the coffee table books full of the amazing images from the Hubble Space Telescope and other famous scopes throughout the world. Even a subscription to a magazine like Sky & Telescope or Astronomy Magazine makes a great gift.

Maybe the most lasting and meaningful gift you can give this year will turn someone on to the great Gift that keeps on giving: our universe, our home.

Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com.

Posted by Administrator at 2003.10.25 01:05 PM | Comments (0)

The Solar System, Cosmology and the Fourth Dimension

The Universe >

One of the key beliefs of western peoples for thousands of years was that the earth was the center of the universe. To everyday man, without the help of sophisticated technology, it does rather appear that way. The Sun, Moon, stars, and planets "go around" us all night and all day. And it doesn’t really feel like we are moving in the slightest.

That idea of an earth-centered or geocentric universe prevailed for a long, long time. But then came more data, better technology, and a liberating Reformation/Renaissance at which time a combination of scientists --- Copernicus, Kepler, Galileo --- could now confidently put the sun at the center of the Whole Shebang.

Theirs was known as the heliocentric universe.

And there was much rejoicing.

That is until we hit the last century. At which time it came to light that, alas, there was no discernible center to the universe! Ready to put on your thinking caps? It’ll be worth it.

Through the works of several insightful and cutting-edge scientists, including Albert Einstein and Edwin Hubble, it appeared both in theory and through the telescope that the universe was getting bigger. It was expanding. And if it is expanding now, it must have been smaller. And if one could rewind time far enough, one could posit that billions of years ago the universe was infinitesimally small --- it had a beginning!

This Creation Event, commonly known as the big bang and currently narrowed down to about 13.7 billion years ago, was a discovery that still has a profound effect on the scientific community. Its theological and philosophical implications alone are worthy of a series of articles if not entire books.

What does this have to do with a center of the universe? Everything. If all matter and energy, and most importantly all space and time, were created in the initial moments of the big bang, then there is no center that we can see. How’s that? It’s time for a classic example to show how.

Let’s say we take an empty balloon and blow into it causing it to expand. The fabric of the balloon represents the surface of a "flat" universe of only two dimensions (up and down, and sideways, like a cross drawn on the balloon). This 2D universe is expanding into a third (depth, or in and out of the balloon like an imaginary stick stuck through).

Draw tiny dots on the balloon. See how as the balloon expands the dots slowly move farther from each other? These dots are like the galaxies in our universe all racing away from each other, riding on the expanding fabric of space.

But notice this also: The center of the balloon is not "on" the balloon. It is "inside" the balloon itself. But one who is confined to the two-dimensional surface of the balloon, able to know only the "stuff" of the balloon --- up, down, and sideways --- cannot point to it. They can’t see the center. It is not a part of where they live.

They’ll need another dimension of space (in and out of the balloon) to observe it.

Our universe consists of our three dimensions of space expanding into (at least) one other dimension, a fourth. Don’t try and picture it; you cannot. Just as a flat person living on the surface of the balloon cannot point to where the "center" is, to where it all began, we cannot point to our center, our point of origin. Such are some of the limitations of being shackled to three dimensions of space expanding into a fourth: we can’t see where we’ve been or where we are going; it is literally beyond us.

Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com.

Posted by Administrator at 2003.10.11 01:07 PM | Comments (0)



Looking for something?	« September 2003 \| Main \| November 2003 » The Skies Above Holiday Gift Guide Observing > If local stores haven't reminded you already with their early displays of nativity scenes and lights and snowmen, we are fast approaching the major gift-giving time of the year. My motives here for reminding you of this are slightly purer than the chain stores'; I am asking you to consider giving gifts this year which will get people excited about the beauties of the cosmos. And now is the time to start considering it. There are all kinds of possible gifts to ponder. Let's start with the most obvious --- telescopes. Please, please, please do not even consider giving someone a cheap department store telescope. The scope whose primary brag line spouts "Magnifies thousands of times!" is the very one to avoid. Too often those store models are poorly made, plastic-lensed rubbish that can better be used for unclogging toilets. Their horrible optics leave the new user utterly frustrated and quickly turned off to the heavens. One of the most important characteristics of a good scope is how much light it can gather. So try and get the biggest mirror or lens size you can reasonably afford. The mirror type of scope, called a reflector (as opposed to the lensed one, called a refractor) is usually the less expensive of the two. There are several other things you should consider and several websites can give you detailed and easily understood hints from the experts. Go see telescope.com, astronomy.com, and skypub.com. And don't forget binoculars! They are more limited than scopes, of course, but they are less expensive and can still provide beautiful wide-angled views of the heavens. If you are buying for someone who has a scope or binoculars already, despair not! There are all sorts of cool gadgets and accessories for scopes --- special eyepieces and filters and lights and chairs and… you get the idea. You can find these items via those websites and at telescope stores. Some local stores that can help you out in your endeavor include Oceanside Photo and Telescope and San Diego's Scope City. They can expertly help you choose scopes and accessories to your heart's delight. Does your gift getter like computers? There are absolutely stunning programs you can buy which turn your computer into a virtual universe. These apps allow you to travel through the galaxy, visit other planets, and see the whole shebang animated with striking accuracy and visual effects. The one I personally use for teaching and in writing this column is Starry Night. It is for both Mac and PC, and is available in different levels of expertise --- e.g. Starry Night Enthusiast or Starry Night Pro. See space.com for details. But shop around for other programs and see what suits your fancy. And of course, there are books --- all kinds of astronomy books --- and any good bookstore should be full of them. There are books on the history of astronomy, the history of the universe, famous astronomers, how to take digital images of heavenly bodies, and all-encompassing college textbooks. And there are the coffee table books full of the amazing images from the Hubble Space Telescope and other famous scopes throughout the world. Even a subscription to a magazine like Sky & Telescope or Astronomy Magazine makes a great gift. Maybe the most lasting and meaningful gift you can give this year will turn someone on to the great Gift that keeps on giving: our universe, our home. Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com. Posted by Administrator at 2003.10.25 01:05 PM \| Comments (0) The Solar System, Cosmology and the Fourth Dimension The Universe > One of the key beliefs of western peoples for thousands of years was that the earth was the center of the universe. To everyday man, without the help of sophisticated technology, it does rather appear that way. The Sun, Moon, stars, and planets "go around" us all night and all day. And it doesn’t really feel like we are moving in the slightest. That idea of an earth-centered or geocentric universe prevailed for a long, long time. But then came more data, better technology, and a liberating Reformation/Renaissance at which time a combination of scientists --- Copernicus, Kepler, Galileo --- could now confidently put the sun at the center of the Whole Shebang. Theirs was known as the heliocentric universe. And there was much rejoicing. That is until we hit the last century. At which time it came to light that, alas, there was no discernible center to the universe! Ready to put on your thinking caps? It’ll be worth it. Through the works of several insightful and cutting-edge scientists, including Albert Einstein and Edwin Hubble, it appeared both in theory and through the telescope that the universe was getting bigger. It was expanding. And if it is expanding now, it must have been smaller. And if one could rewind time far enough, one could posit that billions of years ago the universe was infinitesimally small --- it had a beginning! This Creation Event, commonly known as the big bang and currently narrowed down to about 13.7 billion years ago, was a discovery that still has a profound effect on the scientific community. Its theological and philosophical implications alone are worthy of a series of articles if not entire books. What does this have to do with a center of the universe? Everything. If all matter and energy, and most importantly all space and time, were created in the initial moments of the big bang, then there is no center that we can see. How’s that? It’s time for a classic example to show how. Let’s say we take an empty balloon and blow into it causing it to expand. The fabric of the balloon represents the surface of a "flat" universe of only two dimensions (up and down, and sideways, like a cross drawn on the balloon). This 2D universe is expanding into a third (depth, or in and out of the balloon like an imaginary stick stuck through). Draw tiny dots on the balloon. See how as the balloon expands the dots slowly move farther from each other? These dots are like the galaxies in our universe all racing away from each other, riding on the expanding fabric of space. But notice this also: The center of the balloon is not "on" the balloon. It is "inside" the balloon itself. But one who is confined to the two-dimensional surface of the balloon, able to know only the "stuff" of the balloon --- up, down, and sideways --- cannot point to it. They can’t see the center. It is not a part of where they live. They’ll need another dimension of space (in and out of the balloon) to observe it. Our universe consists of our three dimensions of space expanding into (at least) one other dimension, a fourth. Don’t try and picture it; you cannot. Just as a flat person living on the surface of the balloon cannot point to where the "center" is, to where it all began, we cannot point to our center, our point of origin. Such are some of the limitations of being shackled to three dimensions of space expanding into a fourth: we can’t see where we’ve been or where we are going; it is literally beyond us. Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com. Posted by Administrator at 2003.10.11 01:07 PM \| Comments (0)
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