Constructive Creativity

Sunday, June 25, 2006

To Infinity and Beyond!

In my previous posts, I have attempted to convey various aspects of my life and personality to my kind readers. Those of you who have blogged with me over the past few years know that I have a wide variety of interests (perhaps too many!). In keeping with my established pattern of gradual self-revelation (my blog is definitely not for the impatient busy-body! ;) ), I would like to share with you now a bit of one of my greatest interests, something that has fired my imagination and stirred my inner most being from the time that I was a small child. Prepare yourself for a brief journey through space and time, as we travel from our humble little oasis in the midst of vast desolation to the very edge of the universe. If you haven't already guessed (or peeked at the pictures *naughty audience! ;)*) the subject of this post is truly Astronomical! :)

I would like to turn my spotlite on a very interesting web site. It is currently my only non-friendly link. :) The site is titled "Astronomy Picture of the Day". Apparently, this web site was established at least eleven years ago (as visits to its archives has taught me). All the pictures that I present for your viewing pleasure today are "borrowed" from various APOD posts. Please click on the links below the pictures to see the proper picture credits and also to read a brief explanation of each picture at the corresponding APOD pages. Also, PLEASE click on the pictures themselves! I promise it will be well worth your time to see the magnificent details of the enlarged pics!

Before we begin our journey, I would like to explain a little about the measurement of astronomical distances. The distance between the various stars that are visible in the night sky is truly vast. The brightest things that we can see in the sky when we look up are the Sun, the Moon, and some of the planets of our Solar System. The stars that we can see are present in our own Milky Way Galaxy. There are billions of stars in our galaxy, and far beyond our galaxy, there are billions of other galaxies! On Earth, we think of distance in terms of miles or kilometers, but in space, a much different "yard stick" is needed.

Astronomers have invented at least two new yard sticks to help them to work with the tremendous distances between their objects of interest. One is called the Parsec. If you are really interested, you can look it up, but I have always found it to be very difficult to relate to. The second, is called the Light Year. Now, this unit is fairly easy to understand. Light travels through space at a speed of approximately 186,000 miles per second, or 300,000 kilometers per second. A Light Year is simply the distance that light will travel in a year. Well, these are big numbers, so lets compare it to something within our own Solar System. The distance between the Earth and the Sun is approximately 93,000,000 miles. If we divide that distance by the speed of light, we can see that it takes light 500 seconds to travel from the Sun to the Earth. This is about eight and one third minutes. Thus, the Earth/Sun distance might be called 500 Light Seconds or 8.33 Light Minutes. Now lets compare that to the distance to the nearest star. The star Alpha Centauri is about four Light Years from our Solar System. So, if an astronaut (cosmonaut, taikonaut, or you can make up a name from your own country ;) ) was in a space ship capable of traveling at the speed of light, it would take her/him four years to get from here to Alpha Centauri. How big is our Milky Way Galaxy you might wonder? It is approximately 100,000 Light Years in diameter. According to astronomers, our Solar System is located about 28,000 Light Years from the center of the Milky Way Galaxy. The Galaxy is roughly shaped like a flattened disk, but the disk has a thickness that various from the center outward to the edge. The galactic center is about 30,000 Light Years thick, and where our Solar System lies, the Galaxy is probably at least 10,000 Light Years thick (well, don't quote me on that, I'm just estimating). Anyway, this explains why we see many stars in the sky no matter which direction we look. If our Solar System was located on our galaxy's edge, our view in the night sky would be dramatically different!

Ok, lets look at the first picture. This is a very famous picture taken by the Apollo 8 crew in 1968. The objective of the Apollo 8 mission was to circle the moon and return to Earth. As some of you may remember, the first moon landing happened the following year. I remember this picture from my early childhood. It was one of the first astronomy pics that really made me feel a sense of wonderment and awe! Our Earth is truly beautiful, don't you think?!


To find the next picture, I had to spend quite a lot of time searching the APOD archives. When I found this picture of the Sun, I knew immediately that it was the one! From the APOD description, about 10 Earths could fit in the hook of the solar flare seen in the bottom left of the picture. Now that's really amazing to me! If you follow the link below the picture, you can watch an animated GIF image of the solar flare erupting. Its quite spectacular, I think! :)
Here is a link to an interesting Wikipedia article about the Sun, if you would like to learn more.

Our Glorious Sun

This picture is of the relatively nearby star cluster known as The Pleiades. It is only about 400 Light Years away, and is easily visible to the naked eye in the night sky, if you know where to look. So, it was certainly well known to our ancient ancesters!

The Pleiades

Here is one of the most famous pictures taken by the Hubble Telescope. One widely circulated zoom of this picture, has been dubbed "The Pillars of Creation". It is aptly named, as many new stars, and presumably new solar systems, are forming within this nebula. It is located about 6500 Light Years away.

The Eagle Nebula

This picture came to my attention a few years ago. It has a rather fascinating story, I think! At the center of the Key Hole Nebula, lies the star know as Eta Carinae. This star is about 100 times more massive than our Sun. The nebula is being formed as the giant star throws tremendous quantities of its outer atmosphere into space. It is a signal to astronomers that the star will soon explode as a Supernova. The life span of such giant stars is measured in millions of years. This is quite brief compared to the life span of our small quiet Sun, which is about 10 billion years. Also, not to worry, our Sun will last another 5 billion years or so, and it will never explode! The Key Hole nebula is about 10,000 Light Years away.

The Key Hole Nebula

Here is a very nice picture of our nearest galactic neighbor, the Andromeda Galaxy, which is located about 2,000,000 Light Years away. Andromeda is know as a spiral galaxy for reasons that are immediately obvious in the picture. It is very similar in shape to our own Milky Way Galaxy. From what I have read, the Milky Way Galaxy and Andromeda are speeding toward each other! Eventually, they will collide!! Again, don't get too anxious, this will not happen for a few hundred million years. Andromeda is quite dim, but it is very large (bigger than the Moon) in the sky, and is visible if you live in a part of the world with very dark night skys. It is really unfortunate for us modern city dwellers that night time "light pollution" takes away much of the astronomical beauty that our pre-technological ancestors enjoyed! Is it any wonder that astronomy played such a huge role in the religions of our ancient ancestors?!

The Andromeda Galaxy

The final picture is one that gave me what I would call something of a "religious experience" the first time I saw it (you have really got to click on this pic!). I was literally moved to tears! The picture is known as The Hubble Deep Field image. To make it, the Hubble telescope was trained on the same, apparently nearly empty, spot in the sky for 10 full days (now, that's some serious gyroscopic action! :D )! It took that long to collect enough light to form the picture. The result was astonishing, and it even surprised veteran astronomers! In the picture, there are literally hundreds of galaxies, some of which are more than 10 billion Light Years distant! What really excited me about this image was that I could see so many islands in the vast emptiness of space where there might be other living creatures. Also exciting is the realization that you are looking back in time, back to the universe when it was quite young. Just think, it took 10 billion years for the light from these distant galaxies to reach us, and astronomers think that the universe is about 13 billion years old! Our little planet, in our little galaxy, is really just a tiny part of the vastness of the universe. There is so much out there, so much wonder, so much danger, and so much that we have yet to learn!

The Hubble Deep Field

I would like to close this post with a poem that really touched me years ago when I first read it. It still stirs some powerful emotions inside of me! It is a poem that has very special meaning for many pilots and people who have gone into space. It was composed by a young aviator who died on December 11, 1941 when his plane collided with another over the skies of England. He was only 19 years old on the day of his passing, and he had sent this poem to his parents a few months earlier. I think it is one of the most beautiful poems that I have ever read!

"High Flight"

Oh! I have slipped the surly bonds of earth
And danced the skies on laughter-silvered wings;
Sunward I've climbed, and joined the tumbling mirth
Of sun-split clouds - and done a hundred things
You have not dreamed of - wheeled and soared and swung
High in the sunlit silence. Hov'ring there,
I've chased the shouting wind along, and flung
My eager craft through footless halls of air.
Up, up the long, delirious, burning blue
I've topped the wind-swept heights with easy grace
Where never lark, or even eagle flew -
And, while with silent lifting mind I've trod
The high untrespassed sanctity of space,
Put out my hand and touched the face of God.

John Gillespie Magee, Jr.