ADVANCED optics developed for the United States ``star wars'' defense program can be used to help search for planets outside Earth's solar system, a US astronomer reported Wednesday.
The atmosphere distorts images taken from the ground of stars, making it hard for scientists to tell if there are planets circling other stars, and, thus, whether there is extraterrestrial life.
Roger Angel of the University of Arizona at Tucson modified a military ``adaptive optics'' system to correct the distorting effects of the Earth's atmosphere. He said it could be used to look for planets from an Earth-based telescope.
Adaptive optics systems include advanced electronics, image sensors, a segmented movable mirror, and a computer.
``It seems likely that, by the end of the decade, ground-based observations will either have found planets around nearby main-sequence stars or have shown conclusively that planets of the size of Jupiter are rare,'' Mr. Angel wrote in an article for the science journal Nature.
Angel said no telescope exists now that could find a planet. The Hubble space telescope, now orbiting Earth and photographing objects in space, cannot detect extraterrestrial life, he said. ``Unfortunately, the Hubble telescope will probably lack the sensitivity for optical detection of an extrasolar planet, even of the size and orbital radius of Jupiter...,'' he said.
San Diego-based ThermoTrex Corporation makes adaptive optics systems for the US military and also supplied a system to the University of Arizona.