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We present Spitzer 4.5micron light curve observations, Keck NIRSPEC radial velocity observations, and LCOGT optical light curve observations of PTFO~8-8695, which may host a Jupiter-sized planet in a very short orbital period (0.45 days). Previous work by citet{vaneyken12} and citet{barnes13} predicts that the stellar rotation axis and the planetary orbital plane should precess with a period of $300 - 600$ days. As a consequence, the observed transits should change shape and depth, disappear, and reappear with the precession. Our observations indicate the long-term presence of the transit events ($>3$ years), and that the transits indeed do change depth, disappear and reappear. The Spitzer observations and the NIRSPEC radial velocity observations (with contemporaneous LCOGT optical light curve data) are consistent with the predicted transit times and depths for the $M_star = 0.34 M_odot$ precession model and demonstrate the disappearance of the transits. An LCOGT optical light curve shows that the transits do reappear approximately 1 year later. The observed transits occur at the times predicted by a straight-forward propagation of the transit ephemeris. The precession model correctly predicts the depth and time of the Spitzer transit and the lack of a transit at the time of the NIRSPEC radial velocity observations. However, the precession model predicts the return of the transits approximately 1 month later than observed by LCOGT. Overall, the data are suggestive that the planetary interpretation of the observed transit events may indeed be correct, but the precession model and data are currently insufficient to confirm firmly the planetary status of PTFO~8-8695b.
Hot Jupiters are giant Jupiter-like exoplanets that orbit 100x closer to their host stars than Jupiter does to the Sun. These planets presumably form in the outer part of the primordial disc from which both the central star and surrounding planets ar
We search for signatures of a distant planet around the two-million-year-old classical T-Tauri star CI Tau hosting a hot Jupiter candidate (M_{p} sin{i} ~ 8.1 M_{Jupiter}) in an eccentric orbit (e ~0.3). To probe the existence of an outer perturber,
PTFO 8-8695 (CVSO 30) is a star in the 7-10 million year old Orion-OB1a cluster that shows brightness dips that resemble planetary transits. Although strong evidence against the planet hypothesis has been presented, the possibility remains debated in
We present emph{Herschel} PACS observations of 8 Classical T Tauri Stars in the $sim 7-10$ Myr old OB1a and the $sim 4-5$ Myr old OB1b Orion sub-asscociations. Detailed modeling of the broadband spectral energy distributions, particularly the strong
We report the spectroscopic confirmation of the Kepler object of interest KOI-183.01 (Kepler-423b), a half-Jupiter mass planet transiting an old solar-like star every 2.7 days. Our analysis is the first to combine the full Kepler photometry (quarters