NASA's Kepler Space Telescope Goes Deep-Space Planet Hunting

Five months after its March 6 launch from Cape Canaveral Air Force Station, in Florida, "NASA's new exoplanet-hunting Kepler space telescope has detected the atmosphere of a known giant gas planet," NASA said in a news release. Exoplanets are planets beyond our solar system.

Kepler's find is based on only "10 days of test data collected before the official start of science operations," NASA said, adding that Kepler's observation "demonstrates the extremely high precision of the measurements made by the telescope, even before its calibration and data analysis software were finished."

"As NASA's first exoplanets mission, Kepler has made a dramatic entrance on the planet-hunting scene," Jon Morse, director of the Science Mission Directorate's Astrophysics Division at NASA Headquarters, in Washington, said in a statement. "Detecting this planet's atmosphere in just the first 10 days of data is only a taste of things to come. The planet hunt is on!" 

Kepler is on a three-and-a-half-year mission to search for "planets as small as Earth, including those that orbit stars in a warm zone where there could be water." Kepler is designed to search for exoplanets by" looking for periodic dips in the brightness of stars, which occur when orbiting planets transit, or cross in front of, the stars," NASA said. According to the statement:

The observations were collected from a planet called HAT-P-7, known to transit a star located about 1,000 light years from Earth. The planet orbits the star in just 2.2 days and is 26 times closer than Earth is to the sun. Its orbit, combined with a mass somewhat larger than the planet Jupiter, classifies this planet as a "hot Jupiter." It is so close to its star [that] the planet is as hot as the glowing red heating element on a stove.

The Kepler measurements show the transit from the previously detected HAT-P-7. However, these new measurements are so precise, they also show a smooth rise and fall of the light between transits caused by the changing phases of the planet, similar to those of our moon. [...] The smooth rise and fall of light is also punctuated by a small drop in light, called an occultation, exactly halfway between each transit. An occultation happens when a planet passes behind a star.

Although Kepler's observation is "already the highest precision ever obtained for an observation of this star, Kepler will be even more precise after analysis software being developed for the mission is completed," NASA said.

"This early result shows the Kepler detection system is performing right on the mark," said David Koch, deputy principal investigator of NASA's Ames Research Center, at Moffett Field, Calif. "It bodes well for Kepler's prospects to be able to detect Earth-size planets."

NASA officials said the discovery of light from HAT-P-7 "confirms the predictions by researchers and theoretical models that the emission would be detectable by Kepler."

"When the light curves from tens of thousands of stars were shown to the Kepler science team, everyone was awed; no one had ever seen such exquisitely detailed measurements of the light variations of so many different types of stars," said William Borucki, the principal science investigator and lead author of a paper on the Kepler observations published in the Aug. 7 edition of Science.