| Extrasolar planet | List of extrasolar planets | |
|---|---|---|
| Parent star | ||
| Star | HD 154857 | |
| Constellation | Ara | |
| Right ascension | (α) | 17h 11m 15.7219s |
| Declination | (δ) | –56° 40′ 50.865″ |
| Distance | 223.55 ly (68.54 pc) |
|
| Spectral type | G5V | |
| Orbital elements | ||
| Eccentricity | (e) | >0.25 |
| Orbital period | (P) | 2900 d (7.94 y) |
| Semi-amplitude | (K) | >23 m/s |
| Physical characteristics | ||
| Minimum mass | (m sin i) | 18.4 MJ |
| Discovery information | ||
| Discovery date | 9 February 2007 | |
| Discoverer(s) | O’Toole | |
| Detection method | Doppler spectroscopy | |
| Discovery site | Australia | |
| Discovery status | Published | |
| Other designations | ||
|
HIP 84069 c, SAO 244491 c
|
||
| Database references | ||
| Extrasolar Planets Encyclopaedia |
data | |
| SIMBAD | data | |
HD 154857 c is an unconfirmed extrasolar planet located approximately 224 light-years away in the constellation of Ara, orbiting the star HD 154857. This planet takes at least 1900 days (5.2 years) to orbit the star. It was discovered on 9 February 2007 by O’Toole in Australia using the method Doppler spectroscopy, along with HD 23127 b and HD 159868 b. The orbit has not yet been completely observed, so the values quoted are lower limits. The best fit solution gives a period of 7.94 years and a minimum mass of 18.4 Jupiter masses, which would imply that it is in fact a brown dwarf.