.jpg) The exoplanet 70 Virginis b (min mass ~7.5 MJ) as rendered by Celestia | |
| Discovery | |
|---|---|
| Discovered by | Geoffrey Marcy R. Paul Butler |
| Discovery site |  United States |
| Discovery date | 17 January 1996[1] |
| Doppler Spectroscopy | |
| Orbital characteristics[2] | |
| 0.481 ± 0.003 AU (71,960,000 ± 450,000 km) | |
| Eccentricity | 0.399±0.002 |
| 116.6926±0.0014d | |
| 7239.7±0.1 | |
| 358.8±0.3 | |
| Semi-amplitude | 315.7±0.7 |
| Star | 70 Virginis |
| Physical characteristics[2] | |
| ~1RJ | |
| Mass | ≥7.40±0.02 MJ |
70 Virginis b (abbreviated70 Vir b) is anextrasolar planet approximately 60light-years away in theconstellation ofVirgo. Announced in 1996 byGeoffrey Marcy andR. Paul Butler,70 Virginis was one of the first stars confirmed to have planets orbiting it.[3] When first announced, 70 Virginis b was considered to be within its star'shabitable zone (preferably in the "Goldilocks zone"), but it was later confirmed that the planet has aneccentric orbit, closer to its parent.
70 Virginis b is agas giantextrasolar planet that is 7.4 times themass ofJupiter and is in an eccentric 116-day orbit about its host. Itssurface gravity is expected to be about six to eight times that of Jupiter, while its radius is about the same as Jupiter's. At the time of discovery in January 1996, it was believed that the star was only 29 ly away resulting in the star being lessluminous based on itsapparent magnitude. As a result, the planet'sorbit was thought to be in thehabitable zone and the planet was nicknamedGoldilocks (not too cold or too hot).[4]
TheHipparcos satellite later showed that the star was more distant fromEarth and therefore brighter resulting in the planet being too hot to be in the habitable zone.[5]
