For years astronomers have scanned the heavens beyond the solar system in search of other planets. If they exist -- and evidence is rapidly accumulating that they do -- the possibility greatly increases that some of the planets may be similar to the earth. U.S. and Canadian astronomers last week reported tantalizing discoveries that strengthened that likelihood.
The U.S. team, led by David Latham of the Smithsonian Astrophysical Observatory in Cambridge, Mass., found evidence of what might be a gigantic planet 20 times as large as Jupiter orbiting a star 550 trillion miles away. The Canadians reported nine stars with possible...