HD 20782
| Observation data Epoch J2000.0 Equinox J2000.0 |
|
|---|---|
| Constellation | Fornax |
| Right ascension | 03h 20m 03.5776s |
| Declination | –28° 51′ 14.656″ |
| Apparent magnitude (V) | 7.38 |
| Absolute magnitude (V) | 4.60 |
| Distance | 117 ly (36 pc) |
| Spectral type | G3V |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 20782 is a 7th magnitude G-type main sequence star about 117 light-years away in the constellation of Fornax. HD 20782 is a part of a wide binary system with HD 20781, both stars host a planetary system. This is the first known case of planetary systems around both stars, the primary and secondary in the binary system. The companion is HD 20781. It has a very large angular separation of 252 arcsec, corresponding to 9080 AU at the distance of HD 20782.[1] It is estimated to be 7.1 (± 4) billion years old, with a mass close to that of our Sun.
An extremely eccentric extrasolar planet was announced around the primary star HD 20782 in 2006.[2][3] In 2009 its orbit was narrowed down, and found to have the highest eccentricity of all known exoplanets, which distinction has stood as of 2012.
And in 2011 two also-eccentric (but less so) Neptune-mass planets were announced around the secondary star HD 20781.[4][5]
Planetary systems
HD 20782
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 1.80 ± 0.23 MJ | 1.36 ± 0.12 | 585.86 ± 0.03 | 0.97 ± 0.01[6] | — | — |
HD 20781
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 12.04 ± 1.11 M⊕ | 0.169 ± 0.0028 | 29.15 ± 0.0201 | 0.11 ± 0.06 | — | — |
| c | 15.76 ± 1,20 M⊕ | 0.3456 ± 0.0047 | 85.131 ± 0.1161 | 0.28 ± 0.09 | — | — |
See also
References
- ↑ http://www.aanda.org/index.php?option=com_article&access=bibcode&Itemid=129&bibcode=2007A%2526A...462..345DFUL
- ↑ 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found. (web preprint)
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External links
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Coordinates: 
03h 20m 03.5776s, −28° 51′ 14.656″
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