HD 159868
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 38m 59.526s |
| Declination | −43° 08′ 43.85″ |
| Apparent magnitude (V) | +7.24 |
| Absolute magnitude (V) | +3.63[note 1] |
| Distance | 171.93 ly (52.71 pc) |
| Spectral type | G5V |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 159868 is a yellow dwarf star approximately 172 light-years away in the constellation of Scorpius. The star is thought to be 3.05 times more luminous than the Sun, yet the metallicity is identical to the Sun.
Planetary system
- In 2007, a planet of the star was announced by astronomer Simon J. O'Toole.[1] The planet (designated HD 159868 b) is likely to be a gas giant. The orbit is extremely eccentric at the average distance of 2 astronomical units (AU), ranging as close as 0.62 AU to as far as 3.38 AU. During its orbital period, the planet spends most of its time in the habitable zone of its star.
- In 2012, a second planet of the star was announced by astronomer Robert A. Wittenmyer.[2]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| c | >0.73 ± 0.05 MJ | 1 ± 0.01 | 352.3 ± 1.3 | 0.15 ± 0.05 | — | — |
| b | >2.1 ± 0.1 MJ | 2.25 ± 0.03 | 1178.4 ± 8.8 | 0.01 ± 0.03 | — | — |
See also
References
- 1 2 O'Toole, Simon J.; et al. (2007). "New Planets around Three G Dwarfs". The Astrophysical Journal. 660 (2): 1636–1641. arXiv:astro-ph/0702213
. Bibcode:2007ApJ...660.1636O. doi:10.1086/513563. - 1 2 Wittenmyer; et al. (2012). "The Anglo-Australian Planet Search. XXII. Two New Multi-planet Systems". The Astrophysical Journal. 753 (2). arXiv:1205.2765. Bibcode:2012ApJ...753..169W. doi:10.1088/0004-637X/753/2/169.
Notes
- ↑ The calculation for absolute magnitude applied here is , where is the apparent magnitude and is the luminosity distance in parsecs.
External links
- "HD 159868". Exoplanets. Retrieved 2008-07-19.
- "Notes for star HD 159868". The Extrasolar Planets Encyclopedia. Retrieved 2008-07-19.
Coordinates: 
17h 38m 59.526s, −43° 08′ 43.85″
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