Institute for Astrophysics | University of Hawaii | 2016 Jun 13
[img3="Artist's impression of the simultaneous stellar eclipse and planetary transitA team of astronomers, including University of Hawaii astronomer Nader Haghighipour, will announce on June 13 the discovery of an unusual new transiting circumbinary planet (orbiting two suns). This planet, detected using the Kepler spacecraft, is unusual because it is both the largest such planet found to date, and has the widest orbit. ...
events on Kepler-1647. Such a double eclipse event is known as a syzygy.
(Figure credit: Lynette Cook)"]http://www.ifa.hawaii.edu/info/press-re ... _small.jpg[/img3][hr][/hr]
Reminiscent of the fictional planet Tatooine in Star Wars, circumbinary planets orbit two stars and have two "suns" in their skies. The new planet, Kepler-1647 b, is Jupiter-sized in radius, the largest of all currently known circumbinary planets, and has an orbital period of 3.0 years, the longest of any confirmed transiting planet.
Nearly half of all Sun-like stars are members of gravitationally-bound binary star systems. The most important subset of these systems are the eclipsing binary stars (stars that pass in front of each other, as seen from Earth), because they provide precise stellar masses and sizes. NASA's Kepler Mission has observed nearly 3000 short-period (less than 1000 days) eclipsing binaries. Among these binaries, only nine have been found to host circumbinary planets, including Kepler-1647.
The detection of Kepler-1647 b is significant for two reasons. First, its large size and large orbit are very different from those of all other known circumbinary planets. All of the previously identified Kepler circumbinary planets are Saturn-sized or smaller. Also, most of these planets tend to orbit close to their host binaries, near the so-called "critical instability radius", where if they orbited any closer, the planet's orbit would be dynamically unstable and the planet would be ejected from the system or crash into one of the stars. ...
New Planet Is Largest Discovered that Orbits Two Suns
San Diego State University | 2016 Jun 13
Kepler-1647b: The Largest and Longest-Period Kepler Transiting Circumbinary Planet - Veselin B. Kostov et al
- arXiv.org > astro-ph > arXiv:1512.00189 > 01 Dec 2015 (v1), 19 May 2016 (v2)