Are we alone in this universe
Somewhere far-far away in the universe life exists, other than the life on earth. An alien traveling on his spaceship sends a friendly signal to the people on earth. His message is- Hi! Will you be my friend? Can this be true? Is it fact or fiction? This is what SETI - Search for Extra Terestrial Intelligence, is trying to find out. It is an effort to find whether there are other civilizations as advanced as ours in the solar system.A prominent private organization working in this field is the SETI Institute at California. As a part of their research, they launched Project Phoenix in 1995. Its aim is to catch any radio signals that may be beamed from another intelligent civilization. If the scientists succeed in getting such a signal then they would try to establish contact with the aliens. Frank Drake, the Founder-Director of SETI is credited with giving the Drake Equation in 1961. Through it we can calculate the approximate number of intelligent civilizations that may be present in the universe.By intelligent civilizations we mean those civilizations, which are as technologically advanced as human beings. The equation takes into consideration several factors like the number of sun like stars in our solar system, the no of planets which may be technologically advanced etc. When we multiply together all these factors we get the value for N-the no of transmitting civilizations that may exist in our galaxy. According to estimates made initially the number of habitable planets in our universe is more than 50,000.
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