Of the Cosmos (extended and edited)

Up beyond the clouds and shouting wind, beyond the edge of the sky, lies the Cosmos, infinite and mysterious challenging our notions of who and what we are (from the Smithsonian Intimate Guide to the Cosmos by Dana Berry). Have you ever pondered the possibility of other worlds, civilizations so advanced they conquered time and space? Ever wondered the origins of time and the cause of its eventual demise? Well I will answer all these questions and more.

Let us question the possibility of ET- aliens. There are 100- 400 billion stars in the Milky Way- half of which might have planets, and there are nearly a trillion galaxies in the Cosmos. It is almost certain that there is microbial life out there. But what about higher life forms? Stephen Hawking stated that since life arose early in the history of Earth that it therefore must be common, and if life is not common that it would have arose late in the 10 billion year life the Sun has to live. And that's really just common sense. It is also important to note that extraterrestrials couldn't have visited Earth without leaving profound proof. Carl Sagan said, "Extraordinary claims, require extraordinary evidence." It is very unlikely that we humans will ever directly come in contact with non-earthly life. We may only be able to use radios. What would they look like? So far, we don't know, but, we do know that they won't look anything like us. Although, we may be alone in the Cosmos after all.

What is Mankind's place among the Stars? We are members of families; citizens of cities, counties, states or provinces, and countries; we are denizens of a planet called Earth, which is the third rock from a ball of plasma called the Sun. There are eight planets that orbit the Sun, which itself orbits a random collection of 400 billion stars called the Milky Way. The Milky Way is on a collision course with a galaxy twice its size, and is moving at a speed of 500 million miles an hour. The galaxies are moving away from each other at that same speed (Except those which are in clusters large or small). And eventually the glaxies will become so distant from us, that no light from them will ever reach us in all infinity. But in the most distant time, the galaxies will go out one by one until none are left, and we will have no place among the Stars. When Voyager 2 was on its voyage to the stellar expances of the eloquent Milky Way , Carl Sagan asked that Voyager 2, take a picture of Earth. When the picture was recieved, the air was driven out of the room. Through the rings of Uranus, was a pale blue dot scarcely a speck of dust to us, but that speck of dust is our home, our cradle, our water covered world, our life world, our planet, our Earth. We cannot pollute it, or damage it; we shall not kill its unique life forms, and we shall not wage our tribal warfare upon it. It gave us a home, our only home. We have no other world to go to, this place we must cherish with our lives. If Mother Earth can give us a home, then it can surely take it away. That speck of dust, that pale blue dot, is our place among the Stars.

How did the Cosmos begin? With a BANG! A big one. Contrary to popular belief the Big Bang was not an explosion but an extremely huge expansion of time and space. When time began 13.7 billion years ago there were no stars, until clouds of pure hydrogen and helium came together and ignited. Two hundred million years after the moment of creation the first star was born, but it was no ordinary star- it was a Megastar. Being two hundred million times as massive the Sun it lived for only five minutes, then came the first explosion in the Cosmos. The Megastar went "Hypernova". Then after one hundred million years the universe left the Dark Ages and entered the Age of Quasars. Quasars are a relic of an age long gone, with their jets of gas and dust 100,000 light years long and the extremely bright center of the City of Stars are an ancient trait of a long extinct breed of primordial galaxies.

The Stars. What are they? The Stars are Suns, but very far away. In order to understand what I mean when I say "very far away" think if you were the Sun. If you were the Sun, the nearest Star would be as far away as Mars is to us. Stars are not alive, but they do have lives, of a sort. They begin as clouds of gas- hydrogen and helium mainly- and begin to condense. They swirl faster and faster around a center, growing ever hotter and becoming plasma (The fourth state of matter). Once enough gas is pulled in, the ball of hot gas ignites. Two hydrogen atoms slam into each other creating helium, and thence the clump of plasma becomes a Star. But a Protostar only. The gas is eventually swept away by various sources. Once the gas is cleared away, the Protostar becomes a Main Sequence Star. For most of its life a normal star will be on the Main Sequence. But most of the Stars in the Cosmos have a total mass smaller than that of the Sun, and so will live tens of billions- if not hundreds of billions- of years. A large minority of Stars are like the Sun, and so will live for around ten billion years. Stars with at least one solar mass (the size of the sun) but less than fifteen solar masses will begin to grow larger and cooler, and redder, and thus becoming Red Giants, only after about six bilion years on the Main Sequence. Smaller Stars fade away into nothing, but massive Stars like Eta Carinae will die a fiery death- they blow up. Red Giants blow away their outer layers leaving a white-hot core, which will shine extremely dim for 50 billion years.

How will the Cosmos end? Until about four years ago it was thought that it would end in a Big Crunch- the opposite of the Big Bang. Then it was thought that trillions of years from now galaxies would rip apart, followed by planets and stars, and at the end of time itself all atoms will split in something called, the Big Rip. But it is most likely that in a googol years ( a one followed by a hundred zeros) the now mighty Cosmos will fade, slowly but surely into the night in the Big Chill.

Why bother? Why did Columbus bother to look for a new way to India? To get spices back to Spain quicker. Who knows, maybe in a half a million years the Earth will become uninhabitable and Mankind will need to abandon the cradle and look for a new home on which to ruin. It might- of course- be programed into our vast brain, for what magnificent landscapes and terrifying beasts lay beyond the horizon? Think for a moment, what if our ancestors 10,000 years ago didn't care? There would be no agriculture- for they would not know the seasons- which means no China, Rome, Sparta, Egypt, France, America, or Myspace.com. There would be no civilization. But just like music, art, movies, sports, books, and computers; what true good does studying the universe do for us? None, absolutely none whatsoever. But if you aren't curious enough to push the limits of knowledge like Da Vinci, or Einstien you truly and honestly are not human. So tonight go outside and look up, look up into the farthest reaches of space, and reach down, reach down to the deepest depths of your mind and remember the questions I've asked today, for the mysteries of the Cosmos are yours to solve.