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arXiv · 0811.2606

Direct Imaging of Multiple Planets Orbiting the Star HR 8799

C. Marois·B. Macintosh·T. Barman·B. Zuckerman·I. Song·J. Patience·D. Lafreniere·R. Doyon
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Abstract

Direct imaging of exoplanetary systems is a powerful technique that can reveal Jupiter-like planets in wide orbits, can enable detailed characterization of planetary atmospheres, and is a key step towards imaging Earth-like planets. Imaging detections are challenging due to the combined effect of small angular separation and large luminosity contrast between a planet and its host star. High-contrast observations with the Keck and Gemini telescopes have revealed three planets orbiting the star HR 8799, with projected separations of 24, 38, and 68 astronomical units. Multi-epoch data show counter-clockwise orbital motion for all three imaged planets. The low luminosity of the companions and the estimated age of the system imply planetary masses between 5 and 13 times that of Jupiter. This system resembles a scaled-up version of the outer portion of our Solar System.

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C. Marois, B. Macintosh, T. Barman, B. Zuckerman, I. Song, J. Patience, D. Lafreniere, R. Doyon. 2008-11-16. Direct Imaging of Multiple Planets Orbiting the Star HR 8799. https://doi.org/10.1126/science.1166585

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