Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-02-20
Nature 445:892-895,2007
Astronomy and Astrophysics
Astrophysics
To appear in Nature 22 Feb 2007; 17 pages, 7 figures, includes supplementary information
Scientific paper
10.1038/nature05636
Of the over 200 known extrasolar planets, 14 exhibit transits in front of their parent stars as seen from Earth. Spectroscopic observations of the transiting planets can probe the physical conditions of their atmospheres. One such technique can be used to derive the planetary spectrum by subtracting the stellar spectrum measured during eclipse (planet hidden behind star) from the combined-light spectrum measured outside eclipse (star + planet). Although several attempts have been made from Earth-based observatories, no spectrum has yet been measured for any of the established extrasolar planets. Here we report a measurement of the infrared spectrum (7.5--13.2 micron) of the transiting extrasolar planet HD209458b. Our observations reveal a hot thermal continuum for the planetary spectrum, with approximately constant ratio to the stellar flux over this wavelength range. Superposed on this continuum is a broad emission peak centered near 9.65 micron that we attribute to emission by silicate clouds. We also find a narrow, unidentified emission feature at 7.78 micron. Models of these ``hot Jupiter'' planets predict a flux peak near 10 micron, where thermal emission from the deep atmosphere emerges relatively unimpeded by water absorption, but models dominated by water fit the observed spectrum poorly.
Deming Drake
Harrington Joseph
Horning Karen
Richardson Lee Jeremy
Seager Sara
No associations
LandOfFree
A Spectrum of an Extrasolar Planet does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Spectrum of an Extrasolar Planet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Spectrum of an Extrasolar Planet will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-382824