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News Release 82 of 232

December 11, 2007 10:00 AM (EST)

News Release Number: STScI-2007-44

Hubble Finds that Extrasolar Planet Has a Hazy Sunset


Image: Artist's Concept of Extrasolar Planet's Hazy Atmosphere

Artist's Concept of Extrasolar Planet's Hazy AtmosphereSTScI-PRC2007-44 Artist's Concept

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A team of astronomers, led by Frederic Pont from the Geneva University Observatory in Switzerland, has detected for the first time strong evidence of hazes in the atmosphere of a planet orbiting a distant star. The new Hubble Space Telescope observations were made as the extrasolar planet, dubbed HD 189733b, passed in front of its parent star in an eclipse. As the light from the star briefly passes through the exoplanet's atmosphere, the gases in the atmosphere stamp their unique spectral fingerprints on the starlight. Where the scientists had expected to see the fingerprints of sodium and potassium, there were none; implying that high-level hazes (with an altitude of nearly 2,000 miles) are responsible for blocking the light from these elements. This is an artist's concept of HD 189733b and its parent star.

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Frederic Pont
Geneva University Observatory, Switzerland

Lars Lindberg Christensen
Hubble/ESA, Garching, Germany

Ray Villard
Space Telescope Science Institute, Baltimore, Md.

Image Type: Artwork

Science Credit: F. Pont (Geneva University Observatory, Switzerland)

Image Credit: NASA, ESA, and G. Bacon (STScI)