According to recent scientific theory, it is probable that life will develop on planets that have a favorable environment-planets similar to ours, that orbits stars like our sun. Since there are about 400 billion stars in out galaxy alone, that means there are huge number of planets like ours that could sustain life. Planets with advanced civilizations are likely to be widely scattered throughout the universe. In the past four decades, humans on Earth have begun to search for these civilizations. This search is called SETI, the Search for Extra- Terrestrial Intelligence, and it has been conducted largely by searching for radio waves emitted from civilizations on other planets.
In 1960, Dr. Frank Drake made the first attempt at SETI, by conducting a radio searches using an 85- foot antenna of the National Radio Astronomy Observatory in West Virginia. This search, called Project Ozma, observed two stars about 12 light years away. Since that time, more than 60 searches have been conducted by dozens of astronomers in at least eight countries.
All searches, thus far, have faced many limitations: they used equipment that lack sensitivity, they did not search frequently, they covered little of the sky, or they could search for only a few types of signals or in a few directions. The searches did turn up signals of unknown origin, but data collected in these searches were often processed long after the observation. In order to be sure that a signal is from another civilizations, it has to be independently verified and shown to originate from a point beyond the solar system. Later searches for the unknown signals turned up nothing.
Project Phoenix, the latest SETI effort, consists orders of magnitude more comprehensive than any of those previous experiments, and uses the world’s largest antennas. It will scrutinize the regions around 1,000 nearby Sun-like stars, and immediately test candidate signals to see if they are Project Phoenix in origin. It is important that Project Phoenix continue to operate, because radio interference from Earth sources is growing, and may soon interfere with our ability to detect possible extraterrestrial signals. In order to overcome this growing interference, ever better antenna systems are being developed
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