英語范文背誦精華 24.2 Other Worlds
From what we know of our solar system, it appears unlikely that we wil find intelligent life as we know it on any of the other planets. Some microorganisms and plants might exist, but behings shaped like man or the fabled Martian monsters are not likely. Human life, according to scientists, developed on this planet because of the unique combination of many factors—the earth’s distance from the sun, the composition of our atmosphere, the structure of the earth’s surface the presence of certain organisms on the face of the plant. Yet many ask, are we the only ones in the universe?
Although astronomers have never actually seen a planet outside of our solar system, they now recongnzie that other solar systems exist. With powerful radio telescopes, they have located these distant system. Astronomer Harlow Shapley has estimated that there may be life in the planetary system of one out of a million stars.
Let’s take this million-to-one chance that astronomer Shapley believes and see what the chances really are! Our best scientific information tells us that there are over 100 billion stars in our own galaxy, and that there are about 100 million galaxies in the universe. They means that there are some 10 quintillion stars in the universe. Suppose that only one out of a million of these stars is a sun like our own sun. That would mean hat there are some 10 trillion possible other suns in the universe. Again, let us use Shpley’s one-out-a-million chance to find how many of these suns could possibly have a planet like earth—a planet 93 million miles away, a planet with oxygen in the air for breathing , a planet on which man could live as he does on earth. There would be about 10 million other planets in the universe that could physically resemble the earth. Finally, suppose we use the one-in-a-million chance to find out how many of these have human life just as we have on earth. We would then find that there are 10 other “earths” with human life somewhere in this vast universe.
Naturally, it would be quite a task to find these 10 out of the millions upon of stars and planets in the universe. But if we did, what would man be like? Would he still be in the cave-man stage? Or would he have developed a society far beyond ours? What would happen if we did meet a man from outer space? It is these unknowns and man’s unending thirst for knowledge that take us into space in search of other possible worlds like ours.
