|
 |
 advertisement
| |
|
|
|
|
|
Eleven More Extrasolar Planets Discovered
By SPACE.com Staff
posted: 12:00 pm ET
05 April 2001
|
eso_new_planets_010405 An international team of astronomers from the Geneva Observatory and other research institutes announced the discovery of 11 new planetary companions to solar-type stars. The discoveries include a giant planet that circles its Sun-like central star in an orbit similar to Earth's and whose potential satellites could theoretically be "habitable." The discovery also includes two new multi-planet systems. The masses of these new objects range from slightly less than, to about 10 times the mass of the planet Jupiter. The new detections are based on measured velocity changes of the stars, performed with the CORALIE spectrometer on the Swiss 47-inch (1.2-meter) Leonard Euler telescope at the European Space Observatory's La Silla Observatory. Instruments on telescopes at the Haute-Provence Observatory in France and on the twin Keck telescopes on Mauna Kea, Hawaii were also used to verify the findings. Some of the new planets have unusual characteristics: One is a two-planet system revolving around the star HD 82943 that indicates one orbital period is nearly exactly twice as long as the other -- cases like this (referred to as "orbital resonance") are well known in our own solar system. Another two-planet system around star HD 74156 has a Jupiter-like planet and a more massive planet farther out from the star. They also discovered a planet (at star HD 80606) with the most elongated orbit detected so far, moving between a near point of 3.1 million and far point of 78.9 million miles (5 million and 127 million kilometers) from the central star. At this moment, there are 63 known extrasolar-planet candidates with minimum masses below 10 Jupiter masses, and 67 known objects with minimum masses below 17 Jupiters. The present team of astronomers has detected about half of these.
|
|
|
|
|
