Planets Beyond the Solar System and the Next Generation of Space Missions

The Kepler mission will observe ~120,000 stars to detect 0.01% drops in brightness due to transits of Earth-sized planets, which must be recognized against intrinsic stellar variability, detector and photon noise. We examined a backside-illuminated CCD under Kepler-like conditions, and obtained a total precision of 1.3¥10-5 at a flux of 1010 e-, indicating a detector error of 7¥10-6. Using ACRIM1 solar irradiation measurements as a baseline, we conclude that intrinsic stellar variability, together with the expected photon and detector noise, provide an average SNR of 8 for four transit events, yielding an 85% detection rate with less than one false alarm for the entire mission.

Last update: 10/22/96 11:00:29