TrES-2b
TrES-2b (Kepler-1b) is an extrasolar planet orbiting the star GSC 03549-02811 located 750 light years away from the Solar System. The planet was identified in 2011 as the darkest known exoplanet, reflecting less than 1% of any light that hits it. Reflecting less light than charcoal, on the surface the planet is said to be pitch black. The planet's mass and radius indicate that it is a gas giant with a bulk composition similar to that of Jupiter. Unlike Jupiter, but similar to many planets detected around other stars, TrES-2b is located very close to its star and belongs to the class of planets known as hot Jupiters. This system was within the field of view of the Kepler spacecraft.
Size comparison of TrES-2b with Jupiter | |
| Discovery | |
|---|---|
| Discovered by | O'Donovan et al. |
| Discovery site | California & Arizona, USA |
| Discovery date | August 21, 2006 confirmed September 8, 2006 |
| Transit | |
| Orbital characteristics | |
| 0.03556±0.00075 AU | |
| Eccentricity | 0 |
| 2.47063±0.00001 d | |
| Inclination | 83.62±0.14 |
| Star | GSC 03549-02811 A |
| Physical characteristics | |
Mean radius | 1.272±0.041 RJ |
| Mass | 1.199±0.052 MJ |
| 3.284±0.016 g | |
| Albedo | 0.0136 |
| Temperature | 1885+51 −66 K. |
This planet continues to be studied by other projects, and the parameters are continuously improving. A 2007 study improved stellar and planetary parameters. A 2008 study concluded that the TrES-2 system is a binary star system. This significantly affects the values for the stellar and the planetary parameters.