Extrasolar Planets

The discovery of planets orbiting distant stars is one of the most exciting fields in astronomy today and interest in it is continuously growing. The first discovery of a massive planetary companion (exoplanet) to a main-sequence star opened new horizons to our understanding of how planets form. New research fields are fast emerging, such as the field of Astrobiology which focuses on the study of proto-stellar systems, planets and ultimately life itself.

Over the past few years, systems with massive planets at very small orbital radii have proved to be quite common despite being generally unexpected. It was originally thought that large gas-giant planets cannot form close to their host stars since the stellar wind would have `blown away’ most of the surrounding gas in the disc to a much farther distance. The theoretical formation models have had to be revised in the light of the new discoveries and the way this has been done is by incorporating the idea of protoplanetary migration in the gaseous disk. The protoplanet coevolves with the disk and can move further inwards as the disk gas material gets depleted.

The current number of confirmed exoplanets exceeds 600, with the vast majority having been discovered by radial velocity surveys. These are severely biased towards the detection of systems with massive planets (several times the mass of Jupiter) in small orbits. The only technique with the potential to detect Earth-mass planets from the ground is microlensing. This figure by K. Horne shows the regions probed by the various techniques used to detect planets.


Former LCOGT Postdoc a NASA 2013 Carl Sagan Fellow!

NASA annouced the selection of five exoplanet scientists who will receive the 2013 Carl Sagan Exoplanet Postdoctoral Fellowships today. One is former LCOGT postdoc Avi Shporer. The fellowship, named for the late astronomer, was created to inspire the next generation of explorers seeking to learn more about planets, and possibly life, around other stars. The primary goal of the fellowship program is to support outstanding recent postdoctoral scientists in conducting independent research related to the science goals of NASA's Exoplanet Exploration Program.

Hands-On LCOGT Science at the AAS Meeting!

LCOGT scientists are attending the winter 2013 meeting of the American Astronomical Society (AAS) in Long Beach, CA. In addition to several poster and oral presentations, LCOGT will be hosting a booth in the conference hall all week. Members of our supernovae, exoplanet, and solar system science teams will be there to talk about their science along with our public outreach group who will be demonstrating the cool interactive education projects available through our website.

The PTF Orion Project: a Possible Planet Transiting a T-Tauri Star

We report observations of a possible young transiting planet orbiting a previously known weak-lined T-Tauri star in the 7-10Myr-old Orion-OB1a/25-Ori region. The candidate was found as part of the Palomar Transient Factory (PTF) Orion project. It has a photometric transit period of 0.448413 \pm 0.000040 days, and appears in both 2009 and 2010 PTF data.


HAT-P-39b--HAT-P-41b: Three Highly Inflated Transiting Hot Jupiters

We report the discovery of three new transiting extrasolar planets orbiting moderately bright (V=11.1 to 12.4) F stars. The planets have periods of P = 2.6940 d to 4.4572 d, masses of 0.60 M_J to 0.80 M_J, and radii of 1.57 R_J to 1.73 R_J. They orbit stars with masses between 1.40 M_sun and 1.51 M_sun. The three planets are members of an emerging population of highly inflated Jupiters with 0.4 M_J < M < 1.5 M_J and R > 1.5 R_J.