Scientists map patchy clouds on alien planet Kepler-7b
Astronomers using data from NASA`s Kepler and Spitzer space telescopes were able to create the first cloud map of a planet that is beyond our solar system, a Jupiter-like world known as Kepler-7b.
Washington: Astronomers using data from NASA`s Kepler and Spitzer space telescopes were able to create the first cloud map of a planet that is beyond our solar system, a Jupiter-like world known as Kepler-7b.
The planet is marked by high clouds in the west and clear skies in the east.
Lead author Brice-Olivier Demory of Massachusetts Institute of Technology in Cambridge, said that 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.
He said that they didn`t expect to see oceans or continents on this type of world, but they detected a clear, reflective signature that they interpreted as clouds.
Kepler`s visible-light observations of Kepler-7b`s Moon-like phases led to a rough map of the planet that showed a bright spot on its western hemisphere. But these data were not enough on their own to decipher whether the bright spot was coming from clouds or heat. The Spitzer Space Telescope played a crucial role in answering this question.
Like Kepler, Spitzer can fix its gaze at a star system as a planet orbits around the star, gathering clues about the planet`s atmosphere. Spitzer`s ability to detect infrared light means it was able to measure Kepler-7b`s temperature, estimating it between 1,500 and 1,800 degrees Fahrenheit (1,100 and 1,300 Kelvin).
This is relatively cool for a planet that orbits so close to its star - within 0.06 astronomical unit - and, according to astronomers, too cool to be the source of light Kepler observed. Instead, they determined, light from the planet`s star is bouncing off cloud tops located on the west side of the planet.
The study has been published in the Astrophysical Journal Letters.