| Extrasolar planet | List of extrasolar planets | |
|---|---|---|
| Parent star | ||
| Star | BD+20°2457 | |
| Constellation | Leo | |
| Right ascension | (α) | 10h 16m 44.8635s |
| Declination | (δ) | +19° 53′ 28.974″ |
| Distance | 650 ± 330 ly (200 ± 100 pc) |
|
| Spectral type | K2II | |
| Orbital elements | ||
| Semimajor axis | (a) | 2.01 AU |
| Periastron | (q) | 1.65 AU |
| Apastron | (Q) | 2.37 AU |
| Eccentricity | (e) | 0.18 ± 0.06 |
| Orbital period | (P) | 621.99 ± 10.2 d (1.7029 ± 0.0279 y) |
| Argument of periastron |
(ω) | 126.02 ± 16.54° |
| Time of periastron | (T0) | 53866.95 ± 27.99 JD |
| Semi-amplitude | (K) | ? m/s |
| Physical characteristics | ||
| Minimum mass | (m sin i) | 12.47 MJ |
| Discovery information | ||
| Discovery date | June 10, 2009 | |
| Discoverer(s) | Niedzielski et al. | |
| Detection method | radial velocity | |
| Discovery site | La Silla Observatory | |
| Discovery status | Published | |
| Database references | ||
| Extrasolar Planets Encyclopaedia |
data | |
| SIMBAD | data | |
BD+20°2457 c is a massive extrasolar planet located between 320 to 980 light years away in the constellation of Leo, orbiting the 10th magnitude K-type bright giant star BD+20°2457. It has mass 12.47 times greater than Jupiter and it takes 1.7 years to orbit the star. However, because of its high minimum mass, this object is most probably a brown dwarf (along with BD+20°2457 b) if its true mass is known. In this case, there would be two brown dwarfs in this stellar system that orbits the star. This planet was discovered on June 10, 2009 using the Hobby-Eberly Telescope.