NASA’s Kepler discovers two planets transiting same star
By ANIFriday, August 27, 2010
WASHINGTON - NASA’s Kepler spacecraft has discovered the first confirmed planetary system with two planets transiting the same star.
The planets were named Kepler-9b and 9c.
Kepler’s ultra-precise camera measures tiny decreases in the stars’ brightness that occur when a planet transits them. The size of the planet can be derived from these temporary dips.
“Kepler’s high quality data and round-the-clock coverage of transiting objects enable a whole host of unique measurements to be made of the parent stars and their planetary systems,” said Doug Hudgins.
The observations show Kepler-9b is the larger of the two planets, and both have masses similar to but less than Saturn. Kepler-9b lies closest to the star with an orbit of about 19 days, while Kepler-9c has an orbit of about 38 days.
In addition to the two confirmed giant planets, Kepler scientists also have identified what appears to be a third, much smaller transit signature in the observations of Kepler-9. That signature is consistent with the transits of a super-Earth-sized planet about 1.5 times the radius of Earth in a scorching, near-sun 1.6 day-orbit.
Additional observations are required to determine whether this signal is indeed a planet or an astronomical phenomenon that mimics the appearance of a transit.
The findings will be published in Thursday’s issue of the journal Science. (ANI)
