ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Wednesday, June 12, 1996 TAG: 9606120038
SECTION: NATIONAL/INTERNATIONAL PAGE: A-6 EDITION: METRO
SOURCE: Los Angeles Times
Astronomers report they have discovered a solar system far closer to our sun than any of the previous half-dozen planet discoveries. Moreover, the new planetary system has features strikingly similar to our own.
Evidence presented Tuesday at the American Astronomical Society meeting in Madison, Wis., suggests that the fourth-nearest star from our sun has a Jupiter-sized companion orbiting at about the distance of Saturn - and possibly a second, smaller, companion at the distance of the asteroid belt.
If confirmed, the new planet - just over 8 light-years from Earth in the direction of the Big Dipper - adds another piece of evidence confirming centuries of speculation that planets are common, and that astronomers don't have to look much beyond their own back yards to find them. Some of these, astronomers hope, harbor the potential for life.
``It's the beginning of a whole new field,'' said George Gatewood of the Allegheny Observatory in Pittsburgh, who discovered the planet orbiting a fast-moving star called Lelande 21185. ``We've just lifted up the corner of the first page of the book.''
After decades of false hopes and dashed promises, astronomers have discovered a string of oddball planetary systems since last fall. However, up until now, all have had bizarre features: one planet orbited its parent star in just four days; others were much larger than Jupiter - the giant of our solar system - and orbited much faster (and therefore much closer) to their suns. The closest of the previously discovered planets is at least 40 light-years away.
Gatewood's planetary system, in contrast, looks much more like our own. The planet weighs in with Jupiter's mass, and appears to circle its star at a similar distance. Both possible planets also orbit in the same pancake-flat plane favored by Earth's planetary companions.
Traveling at light speed, which is not possible, one could make the nearly 50trillion-mile journey to Lelande 21185 in just over eight years. Prospects for life there are dim, however, because all large planets previously discovered are mostly gas, lacking any solid ground. In addition, the star itself is too faint to generate enough heat to support life as we know it.
Curiously, the latest discovery was not the result of space-age technology as much as persistence and patience. The Pittsburgh observatory had been keeping track of Lelande 21185 for more than six decades with a 30-inch telescope - small by modern standards.
By plotting the star's course through the heavens, they were able to discern a small wobble in its motion - rather like a car weaving in and out of traffic lanes. Instead of being steered, however, the star was being pulled side to side by the gravitational influence of the planet.
Only recently, however, did the telescope get new optics that allowed Gatewood to see the star with 10 times the previous precision. ``That's what gave us the nerve to announce this,'' he said.
Gatewood has a reputation for careful observing, and in fact proved several previous planet sightings in the 1960s to be false.
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