NASA Space Telescopes Detect Patchy Clouds on Exoplanet 'Kepler-7b’
Astronomers have formed a cloud map of a Jupiter-like exoplanet, 'Kepler-7b' , found beyond our solar system.
Based on analysis of the data offered by NASA's Kepler and Spitzer telescopes, the astronomers created a first cloud map of the distant world.
"By observing this planet with Spitzer and Kepler for more than three years, we were able to produce a very low-resolution 'map' of this giant, gaseous planet," Brice-Olivier Demory of Massachusetts Institute of Technology in Cambridge, said in a press statement. "We wouldn't expect to see oceans or continents on this type of world, but we detected a clear, reflective signature that we interpreted as clouds."
Kepler-7b was one of the first exoplanets discovered by Kepler in its over 3-year search. Till date it has found above 150 exoplanets. For the moment the telescope is out of commission due to technical issues.
Kepler's probe detected the presence of a bright spot on the planet's western hemisphere. But due to insufficient data, the astronomers couldn't interpret whether the bright spot was due to internal heat or it was being emitted from the clouds. To decode this mystery, the astronomers used the Spitzer Space telescope to gather hidden clues of the planet's atmosphere.
Spitzer's ability to detect the infrared light enabled it to measure Kepler-7b's temperature ranging from 1,500-1,800 degree Fahrenheit. For a planet that orbits its star from such a close distance, this temperature is comparatively cooler. The temperature is too cool to host the light observed in Kepler's western hemisphere. Considering this fact, the astronomers believe that the light from the planet's star might be coming from the clouds on the western side of the planet.
"Kepler-7b reflects much more light than most giant planets we've found, which we attribute to clouds in the upper atmosphere," said Thomas Barclay, Kepler scientist at NASA's Ames Research Center in Moffett Field, Calif. "Unlike those on Earth, the cloud patterns on this planet do not seem to change much over time -- it has a remarkably stable climate."
The researchers emphasize that this technique will be useful in studying the atmosphere of those planets that have Earth like composition and size.
"With Spitzer and Kepler together, we have a multi-wavelength tool for getting a good look at planets that are billions of miles away," said Paul Hertz, director of NASA's Astrophysics Division in Washington. "We're at a point now in exoplanet science where we are moving beyond just detecting exoplanets, and into the exciting science of understanding them."
The findings will be published in the journal the Astrophysical Journal Letters.