Careful follow-up observations of nearby transiting planet systems have revolutionized our understanding of a whole new kind of planet: hot Jupiters. They have been used to reveal absorption by atmospheric atomic sodium (Charbonneau et al. 2002) and the presence of an extended hydrogen exosphere (Vidal-Madjar et al. 2003) in HD209458b, as well as to detect the thermal infrared emission from TrES-1, HD209458b, and HD189733b (Charbonneau et al. 2005; Deming et al. 2005; Deming et al. 2006). They have been used to investigate the spin-orbit alignment of HD209458b (Queloz et al. 200, Winn et al. 2005) and HD189733b (Winn et al. 2006). Most recently, spectra of the infrared planetary emission of HD189733b (Grillmair et al. 2007) and HD209458b (Richardson et al. 2007), obtained with the Spitzer Space Telescope, have been used to constrain models of the atmospheric content of those planets. The fourteen transiting planets have provided the first clues about the physics of these other worlds.
Matthew Holman (CfA) and Josh Winn (MIT) have begun the Transit Light Curve (TLC) Project, a program of monitoring transiting planets with CfA telescopes. The principal goals of the project: (1) to refine the estimates of the physical and orbital parameters of these systems; (2) to search for evidence of additional planets; and (3) to search for the reflected light of the planet near the times of secondary eclipse.
Matthew J. Holman