Gliese 876
Encyclopedia : G : GL : GLI : Gliese 876
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|- ! style="background-color: #FFFFC0;" colspan="2" | Details |- |style="vertical-align: baseline;" | Mass | M☉ |- |style="vertical-align: baseline;" | Radius | R☉ |- |style="vertical-align: baseline;" | Luminosity | L☉ |- |style="vertical-align: baseline;" | Temperature | K |- |style="vertical-align: baseline;" | Metallicity | |- |style="vertical-align: baseline;" | Rotation | |- |style="vertical-align: baseline;" | Age | })<()or(}})=()and(}})<())}}} years
|- ! style="background-color: #FFFFC0;" colspan="2" | Other designations |- | colspan="2" |
|}Gliese 876 (also known as IL Aquarii; Gl 876 for short) is a red dwarf star approximetaly 15 light-years away in the constellation Aquarius. It has the variable star designation IL Aquarii. Gliese 876 is only half the size of our Sun along with mass and brightness.
Planetary system
Gliese 876 has been found to be orbited by at least two large planets which are locked in a 2:1 orbital resonance, as well as one smaller terrestrial planet. It is so far one of only a few red dwarfs with known extrasolar planets, another being Gliese 436.In June 2005 the National Science Foundation announced the discovery of the first possibly Earth-like sized extrasolar planet in orbit around Gliese 876 (Gliese 876 d). The discoverers estimate the minimum mass for the planet of 5.9 Earth masses, with a period of 1.94 days at a distance of 0.021 astronomical unit (AU) (3.14 Gm or 2 million miles), about ten times the distance the Moon is from Earth.
| Companion (In order from star) | (Jupiter (planet)>MJ) | Orbital period (days) | (Astronomical unit>AU) | Eccentricity |
|---|---|---|---|---|
| d | 0.023 ± 0.003 | 1.94 | 0.021 | 0 |
| c | 0.56 | 30.12 | 0.13 | 0.27 |
| b | 0.023 ± 0.003 | 60.02 | 0.21 | 0.10 |
See also
References
- Alpert, Mark (Nov. 2005). "Red Star Rising". Scientific American, p. 15.
External links
- [BBC: Smallest extrasolar planet found]
- [Gliese 876-Extrasolar Visions]
- [A planet for Gliese 876]
- [Science News Online-Two teams find planet orbiting nearby star]
- [Gliese 876 : THE CLOSEST EXTRASOLAR PLANET]
- [Gliese 876d Pictures]
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