Gliese 570
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 GJ 570 D looking at star A (right) and BC (left) |
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| Observation data Epoch J2000.0 |
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|---|---|
| Constellation (pronunciation) |
Libra |
| Right ascension | 14h 57m 28.0/27.2s |
| Declination | -21° 24' 55/56" |
| Apparent magnitude (V) | 5.64 / ? / 9.90 |
| Characteristics | |
| Spectral type | K4V / M1V / M3V / T7V |
| U-B color index | 1.06 /1.22 /? |
| B-V color index | 1.11 / 1.51 / ? |
| Variable type | not / ? |
| Astrometry | |
| Radial velocity (Rv) | +27.9 km/s |
| Proper motion (μ) | RA: 1034.18 mas/yr Dec.: -1725.60 mas/yr |
| Parallax (π) | 169.85 ± 0.82 mas |
| Distance | 19.2 ± 0.09 ly (5.89 ± 0.03 pc) |
| Absolute magnitude (MV) | 6.79 / ? / 11.05 |
| Details | |
| Mass | 0.76 / 0.55 / 0.35 / 0.05 M☉ |
| Radius | 0.77 / 0.65 / ? R☉ |
| Luminosity | 0.16 / 0.02 / 0.003 / 3•10-6 L☉ |
| Temperature | 4170 / 2700 / ? K |
| Metallicity | 102% |
| Rotation | 48.3 days |
| Age | ? years |
| Other designations | |
Gliese 570 (also known as HR 5568) is a trinary star about 19.2 light-years away in the constellation Libra. The system consists of an orange dwarf primary, a binary star set of red dwarfs, and a far out brown dwarf. The system is located southwest of Alpha Librae. It is the closest star system in Libra.
Contents |
[edit] Gliese 570 A
Gliese 570 A is the primary star in the system.
[edit] Gliese 570 Ab
Gliese 570 Ab was an unconfirmed extrasolar planet orbiting Gliese 570 A. The planet was hypothesised by Martin Kürster in 1998 and retracted in 2000.[1]
[edit] Gliese 570 BC
Gliese 570 BC are a set of red dwarfs orbiting each other around the primary star. The pair orbit star A at about 190 AUs with a 2,130 year orbit and an eccentricity of 0.20[2]. Star B orbits about 0.31 AUs from the BC center and C orbits 0.48 AUs from the BC center and they orbit each other every 0.846 years.
[edit] Gliese 570 D
Gliese 570 D is the farthest object in the system and is a brown dwarf with a mass between 30 and 70 Jupiter masses (0.05±0.02 solar masses) and about 3•10-6 times the solar luminosity. Its separation from Gliese 570 A is at least 1500 AU[3].
[edit] See also
[edit] References
- ^ Kurster et al. (2000). "The planet search program at the ESO Coud´e Echelle spectrometer I. Data modeling technique and radial velocity precision tests". Astronomy and Astrophysics 362: 585-594.
- ^ Sixth Catalog of Orbits of Visual Binary Stars (looked up 18.05.2008)
- ^ Burgasser et al. (2000). "Discovery of a Brown Dwarf Companion to Gliese 570ABC: A 2MASS T Dwarf Significantly Cooler than Gliese 229B". The Astrophysical Journal 531 (1): L57-L60.
