Submitted on September 30, 2008
Accepted on November 5, 2008
Direct Imaging of Multiple Planets Orbiting the Star HR 8799
Christian Marois 1*, Bruce Macintosh 2, Travis Barman 3, B. Zuckerman 4, Inseok Song 5, Jennifer Patience 6, David Lafrenière 7, René Doyon 8
1 National Research Council Canada Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC, V9E 2E7, Canada.; Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA.; Astronomy Department, University of California, Berkeley, CA 94720, USA.
2 Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA.
3 Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001, USA.
4 Physics & Astronomy Department and Center for Astrobiology, University of California, Los Angeles, CA 90095, USA.
5 University of Georgia, Physics and Astronomy, 240 Physics, Athens, GA 30602, USA.
6 University of Exeter, School of Physics, Stocker Road, Exeter, EX4 4QL, UK.
7 Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4, Canada.
8 Département de Physique and Observatoire du Mont Mégantic, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada.
* To whom correspondence should be addressed.
Christian Marois , E-mail: christian.marois{at}nrc-cnrc.gc.ca
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 toward 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 counterclockwise 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.
