Exoplanet | List of exoplanets | |
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Parent star | ||
Star | Gliese 581 | |
Constellation | Libra | |
Right ascension | (α) | 15h 19m 26s |
Declination | (δ) | −07° 43′ 20″ |
Apparent magnitude | (mV) | 10.56 to 10.58 |
Distance | 20.37 ly (6.26 pc) |
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Spectral type | M3V | |
Mass | (m) | 0.31 M☉ |
Radius | (r) | 0.29 R☉ |
Temperature | (T) | 3480 ± 48 K |
Metallicity | [Fe/H] | -0.33 ± 0.12 |
Age | 7 – 11 Gyr | |
Orbital elements Epoch JD 2451409.762 |
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Semi-major axis | (a) | 0.21847 ± 0.00028AU |
Eccentricity | (e) | 0 |
Orbital period | (P) | 66.87 ± 0.13d (0.183 y) |
(1600 h) | ||
Mean anomaly | (M) | 56 ± 27° |
Semi-amplitude | (K) | 1.91 ± 0.22m/s |
Physical characteristics | ||
Mass | (m) | 6.98M⊕ |
Radius | (r) | 2.20 R⊕ |
Stellar flux | (F⊙) | 0.27 ⊕ |
Discovery information | ||
Discovery date | 24 April 2007 | |
Discoverer(s) | Udry et al. | |
Discovery method | Radial velocity | |
Discovery site | La Silla Observatory, Chile | |
Discovery status | Possibly confirmed | |
Other designations | ||
HO Librae d, HO Lib d, BD−07°4003 d, GJ 581 d, HIP 74995 d, LFT 1195 d, LHS 394 d, LPM 564 d, LTT 6112 d, NLTT 39886 d, TYC 5594-1093-1 d, Wolf 562 d.
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Database references | ||
Extrasolar Planets Encyclopaedia |
data | |
SIMBAD | data | |
Exoplanet Archive | data | |
Open Exoplanet Catalogue | data |
Gliese 581 d /ˈɡliːzə/ (often shortened to Gl 581 d or GJ 581 d) is a possible extrasolar planet orbiting the star Gliese 581 approximately 20.4 light-years away in the constellation of Libra. It is the third planet claimed in the system and (assuming a six-planet model) the fifth in order from the star.
Though not confirmed to be a terrestrial planet and significantly more massive than Earth (at 6.98 Earth masses), the Super-Earth is the first exoplanet of terrestrial mass proposed to orbit within the habitable zone of its parent star.
Assuming its existence, computer climate simulations have confirmed the possibility of the existence of surface water and these factors combine to a relatively high measure of planetary habitability.
A team of astronomers led by Stéphane Udry of the Geneva Observatory used the HARPS instrument on the European Southern Observatory 3.6 meter telescope in La Silla, Chile to discover the planet in 2007. Udry's team employed the radial velocity technique, in which the mass of a planet is determined based on the small perturbations it induces in its parent star’s orbit via gravity.