37th DPS Meeting, 4-9 September 2005
Session 31 Extrasolar Planets
Poster, Tuesday, September 6, 2005, 6:00-7:15pm, Music Recital Room

[Previous] | [Session 31] | [Next]

[31.07] Separating Extrasolar Planetary Photons from Stellar Ones

R. Jagpal, B. Quine, J. Caldwell (York University (Toronto))

Spatial resolution of the light reflected by extra-solar planets from the light of their parent stars is financially and technically challenging. However, the properties of one of the most common types of extra-solar planets found to date, "hot Jupiters", suggest another approach to their study. The majority of extrasolar planets have been discovered through an analysis of stellar spectra in order to detect velocity variations induced by the presence of large, close-orbiting planets. However, the close proximity of hot Jupiters to their stars results in detectable brightness levels of reflected planetary light, about 10,000 times Jupiter's reflected light. Thus, the spatially unresolved stellar spectra also contain light reflected directly from the visible level of these planetary bodies. The orbital velocities and resultant Doppler shifts of the planets are about 1000 times greater than the stellar "wobble". The magnitude and phase of the Doppler shifts of the planets can be found from the original stellar wobble. We are investigating practical considerations and methodology needed to extract planetary information from the known Doppler variation of the reflected planetary signal from that of the parent star, in the presence of noise. Our approach employs a Monte-Carlo simulation of the combined star-planet observation in order to predict accurately the time variation of the expected combined spectra. We propose to use this analysis to develop a means to separate a planetary spectrum from the stellar one in order to investigate planetary inhomogeneity, including albedo variations across the disk of the planet, if they exist, and to determine detailed planetary spectra in order to infer atmospheric composition.

[Previous] | [Session 31] | [Next]

Bulletin of the American Astronomical Society, 37 #3
© 2004. The American Astronomical Soceity.