Tuesday, December 14, 2010

Astrology » Where is extraterrestrial?

One day in 1950, Nobel laureate, physicist Enrico Fermi and the other 3 physicists lunched at the dinner table, Fermi suddenly said one sentence: "where are they? "Other people quickly realized that Fermi was still pondering what they just argued about the spacecraft and alien. Later, Fermi's words became the famous "Fermi Paradox."

"Fermi paradox" is connotative of this meaning: In theory, humans can use 100 million years of time to fly to every planet of the galaxy, then the aliens as long as their evolution is 100 million years earlier than humans, they should now come to the Earth. Why do they not come? Where is their precise whereabouts?
The reason that this paradox has persuasion is because it is based on two facts of Milky Way galaxy: First, the Milky Way galaxy is very old, about 100 million years of age; second, the diameter of the Milky Way galaxy is only about 10 million light-years. Therefore, even if the alien is only traveling in space in the speed of one-thousandth of the speed of light, they can only take about one million years across the universe - this time is far shorter than the age of the universe. If aliens really exist, then they should arrive very earlier.

This paradox afflicts those scientists working hard to explore extraterrestrial life. For half a century, spacecraft have visited or detected the vast majority of the solar system planets and major satellites, but did not find any signs of life. Astronomers also tracked microwave signals sent by hundreds of thousands of stars, so far still draw a blank. Undeniably, we are detecting only a small number of the planet and a solar system, while the broad expanse of the Milky Way galaxy has 1 more than 200 billion stars. The question of looking for extraterrestrial civilizations becomes: how many planets having the same environment with earth exist in the Milky Way galaxy? But the "Fermi Paradox "still has not been resolved.
If the logical analysis of Fermi is correct, it will become the nightmare of all astronomers who have made great efforts to find extraterrestrial life, the " exploration of extraterrestrial civilization, life" projects will also be in vain. But people full of enthusiasm still can find the space to continue to study. One theory to deal with the "Fermi paradox" is: Star Trek is too difficult and expensive, so that aliens could not take place. Another is called "Zoo theory" which explains that the aliens on earth at least are watching us somewhere, but they vow not to interfere with human activities, just as the actions that human adopt to those endangered species and ancient civilizations.

In any case, scientists are still adhering to find, they often use such words to encourage themselves: "the evidence does not exist, not non-existent evidence."

ARTICLE SOURCE: Jessie