spacetoday.net: More extrasolar planets discovered

Posted: Wed, Jan 10, 2001, 12:35 AM ET (0535 GMT)
Astronomers announced Tuesday the discovery two more extrasolar planets, including one more massive than any planet yet discovered. A team led by veteran planet discoverer Geoff Marcy said they found a planet orbiting HD 168443, a Sun-like star 123 light-years away, with a mass 17 times that of Jupiter. Such bodies are usually classified as brown dwarfs, but its proximity to the star -- less than 3 AU away -- as well as the existence of a smaller planet even closer to the star led them to reconsider that classification. The same team also found another planet orbiting tiny Gliese 876, a M-type star 15 light-years away, with an orbital period of 30 days, exactly half that of a previously-discovered planet. Astronomers believe the two planets are locked in a 2:1 resonance, the first gravitational resonance seen in an extrasolar planetary system. There are now 55 known extrasolar planets in our celestial neighborhood, with a number of search programs ongoing to look for more.