2 NEW PLANETS DISCOVERED NEAR SUN-SIZE STARS.

Byline: John Noble Wilford The New York Times

In a stunning discovery of new worlds far out in the universe, two California astronomers on Wednesday reported the detection of two planets orbiting sun-like stars.

The temperatures of the planets appear to be warm enough for water to exist in liquid form, a condition conducive to chemical processes that could, just possibly, be producing extraterrestrial life.

The two newly discovered extra-solar planets, considerably larger than Jupiter, accompany the stars 70 Virginis, in the constellation Virgo, and 47 Ursae Majoris, in the Big Dipper, or Ursa Major. They are 35 light-years away, relatively close by cosmic standards. They are too small and dim to be seen against the glare of their parent stars, but their gravitational presence has been definitely established.

The discovery of the planets, together with another one found in October, encouraged scientists in their growing belief that the solar system is anything but unique and that other planetary systems may be fairly common. This, in turn, was seen as raising the likelihood that life exists elsewhere in the universe, perhaps even intelligent life.

The announcement, made here at a meeting of the American Astronomical Society, followed two other startling findings made public this week at the gathering: an increase in the estimated number of detectable galaxies in the universe, to 50 billion from 10 billion, and evidence that burned-out stars may account for at least half the missing mass in the universe.

The latest discovery was greeted with enthusiasm and widespread endorsement by other astronomers, many of whom could hardly wait to have a look with their own telescopes and possibly find other planets. They used terms like "provocative" and "profoundly exciting" to describe the findings.

"We truly are at the dawn of a new era in astronomy," said Dr. Alan P. Boss, a theoretical astronomer at the Carnegie Institute in Washington. "We will be finding many more planets in the next decade."

In a similar vein, Dr. William J. Boruchi, an astronomer at the Ames Research Center in Mountain View, Calif., who is also searching for extra-solar planets, said: "It's almost like the second coming of Marco Polo or Columbus. We're finding new worlds."

In the afterglow of this discovery, the National Aeronautics and Space Administration announced at another session of the conference that one of its highest scientific priorities over the next 25 years would be a concerted effort, using ground-based telescopes and new spacecraft systems, to search the heavens for other planetary bodies. Some of the proposed instruments might be capable of taking pictures of other planets, even those as small as Earth, and examining their reflected light for direct evidence of their composition and potential for life.

The two newly found planets were discovered by Dr. Geoffrey W. Marcy, an astronomer at San Francisco State University who is a visiting scholar at the University of California at Berkeley, and his research associate, Dr. Paul Butler, affiliated with the same universities. The findings were a culmination of eight years of work using the 120-inch telescope at Lick Observatory near San Jose, Calif.

The two astronomers had previously confirmed the first discovery, announced by Swiss scientists in October, of a planet around another ordinary star, 51 Pegasi, about 40 light-years away. The Pegasi planet is only about half the mass of Jupiter, however, and is so close to its star that it is baking hot and unable to support life.

"After the discovery of 51 Pegasi, everyone wondered if it was a freak, a one-in-a-million observation," Marcy said. "The answer is no. Planets aren't rare after all."

Marcy and Butler made the detections by observing variations in the light from the stars. Those variations were in a pattern suggesting a slight wobble caused by the gravitational force of a massive planet in nearby orbit. The patterns were so regular, just as Kepler and Newton would have predicted, Marcy said, that there is "almost no other explanation besides a planet to produce it."

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