Monday, December 1, 2014
STARRY, STARRY NIGHT (or, Is Anyone Out there?) by Shirley Martin
Of all the physical sciences, none seems to defy logic and understanding as does astronomy. Or so it seems to me. The numbers alone challenge understanding. For example, when astronomers state that the universe was created in one billionth of a second, the time element seems incomprehensible. Yet that's the time span given for the Big Bang--a cosmic explosion of an intensely hot fireball that resulted in the creation of the universe, about twenty-billion years ago.
To better understand the time span from the creation of the universe to man's appearance on Earth, think of a twenty-four hour clock. Man appears in the last few seconds before midnight.
The universe is so vast that its size, too, defies understanding. More than one-billion stars comprise our galaxy, the Milky Way galaxy. And there are millions of galaxies in the universe. Does that give you an idea of its immense size? Furthermore, the universe is expanding at a tremendous rate. That means that stars, planets, and all heavenly bodies are moving away from each other. The more remote the body, the faster it's moving. This expansion of the universe is called "the red shift."
If you can get away from city lights and look up at the night sky, you'll see a countless number of stars shining in the heavens. With all of these stars in the night sky--millions and millions--the night sky should be a blinding sheet of light. Yet it isn't. The night sky is dark. The darkness of the night sky presented a paradox to astronomers in the past. (Many may not know it, but Edgar Allan Poe was a skilled astronomer. The dark night sky puzzled him, too.)
The puzzle was eventually resolved in the deliverance of time. Stars don't shine forever. They shine for millions or billions of years, and then they burn out. The first stars began shining about fifteen-billion years ago. So why is the night sky dark? When we look far out in space, we are looking back in time. We see the light of the stars, but they are no longer there. They died out years ago, but their light is just now reaching us. The farther out in the sky we look, the farther we are looking back in time. It has taken millions of years for their light to reach us, even though they died out eons ago. The sky is an image of the past.
The astronomers' term for this relationship between time and space is referred to as "lookback time." It was Albert Einstein who proved that space and time are interwoven.
I used to wonder what the edge of the universe looked like. If the universe is finite--if it has an end--then what lies beyond it? Now astronomers state that there are many universes, going on and on.
Now considering our own universe, with its billions and billions of stars, one might wonder if there is intelligent life beyond our planet. Can there be an Earthlike planet, with just the right ingredients for intelligent life? Scientists refer to this as the Goldilocks criteria, not too hot and not too cold. SETI--The Search for Extraterrestrial Intelligence--has been seeking intelligent life elsewhere for years. But even if there is intelligent life elsewhere, how could we reach them, or how could they reach us? Distance appears to be an insurmountable problem. According to the laws of physics, nothing travels faster than the speed of light. It could take men on earth thousands, even millions of years to reach a habitable planet, a self-defeating pursuit. Wormholes, if they exist, can be dangerous. So how could we travel to outer space? All you Trekkies, do you have an answer?
I can't conclude this discussion without saying something about the Christmas Star, or the Star of Bethlehem. Scientists now know that the Star of Bethlehem wasn't a star but a planet--most likely Venus, or a conjunction of Venus and Jupiter--shining brightly over the town of Bethlehem.
For those who want to read more about the universe, "The Red Limit" by Timothy Ferris is a good place to start.
If fiction is more your cup of tea, may I suggest my own books with Books We Love. You can find them here at http://bookswelove.net/martin.php and at Amazon. I write historical, paranormal, and fantasy romance, so you have a varied selection to choose from.