HD 22781
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 03h 40m 49.5246s[1] |
| Declination | +31° 49′ 34.6489″[1] |
| Apparent magnitude (V) | 8.78[2] |
| Characteristics | |
| Evolutionary stage | main-sequence star[3] |
| Spectral type | K0[2] |
| Astrometry | |
| Radial velocity (Rv) | 8.26[1] km/s |
| Proper motion (μ) | RA: 40.576[1] mas/yr Dec.: −94.254[1] mas/yr |
| Parallax (π) | 30.6433 ± 0.1071 mas[4] |
| Distance | 106.4 ± 0.4 ly (32.6 ± 0.1 pc) |
| Details[5] | |
| Mass | 0.75±0.02 M☉ |
| Radius | 0.70±0.02 R☉ |
| Surface gravity (log g) | 4.57±0.04 cgs |
| Temperature | 5175±15 K |
| Metallicity [Fe/H] | −0.35±0.02 dex |
| Rotational velocity (v sin i) | 1.73[3] km/s |
| Age | 4.14±3.63 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 22781, is a single star about 106 light-years away. It is a K-type main-sequence star. The star’s age is poorly constrained at 4.14±3.63 billion years, but is likely similar to that of the Sun.[5] HD 22781 is heavily depleted in heavy elements, having just 45% of Sun's concentration of iron,[2] yet is comparatively rich in carbon, having 90% of Sun`s abundance.[5]
An imaging survey in 2012 has failed to find any stellar companions, suggesting HD 22781 is a single star.[6]
Planetary system
[edit]In 2011 a transiting superjovian planet or brown dwarf b was detected on an extremely eccentric orbit.[3] It is located just outside of the conservative habitable zone of the parent star.[7] Planets around such metal-poor stars are rare; the only three known similar cases are HD 111232 and HD 181720.[8]
In 2012, a radial velocity data review indicated there are no additional giant planets in the system.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥13.65±0.97 MJ | 1.167±0.039 | 528.07±0.14 | 0.8191±0.0023 | — | — |
References
[edit]- ^ a b c d e f "HD 22781". SIMBAD. Centre de données astronomiques de Strasbourg.
- ^ a b c Maldonado, J.; Villaver, E.; Eiroa, C.; Micela, G. (2019), "Connecting substellar and stellar formation. The role of the host star's metallicity", Astronomy & Astrophysics, 624: A94, arXiv:1903.01141, Bibcode:2019A&A...624A..94M, doi:10.1051/0004-6361/201833827, S2CID 118934484
- ^ a b c d Díaz, Rodrigo F.; Santerne, Alexandre; Sahlmann, Johannes; Hébrard, Guillaume; Eggenberger, Anne; Santos, Nuno C.; Moutou, Claire; Arnold, Luc; Boisse, Isabelle; Bonfils, Xavier; Bouchy, François; Delfosse, Xavier; Desort, Morgan; Ehrenreich, David; Forveille, Thierry; Lagrange, Anne-Marie; Lovis, Christophe; Pepe, Francesco; Perrier, Christian; Queloz, Didier; Ségransan, Damien; Udry, Stéphane; Vidal-Madjar, Alfred (2012), "The SOPHIE search for northern extrasolar planets IV. Massive companions in the planet-brown dwarf boundary", Astronomy & Astrophysics, A113: 538, arXiv:1111.1168, Bibcode:2012A&A...538A.113D, doi:10.1051/0004-6361/201117935, S2CID 55322205
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c Maldonado, J.; Villaver, E. (2017), "Searching for chemical signatures of brown dwarf formation", Astronomy & Astrophysics, 602: A38, arXiv:1702.02904, Bibcode:2017A&A...602A..38M, doi:10.1051/0004-6361/201630120, S2CID 56225222
- ^ Ginski, C.; Mugrauer, M.; Seeliger, M.; Eisenbeiss, T. (2012), "A lucky imaging multiplicity study of exoplanet host stars", Monthly Notices of the Royal Astronomical Society, 421 (3): 2498–2509, arXiv:1202.4586, Bibcode:2012MNRAS.421.2498G, doi:10.1111/j.1365-2966.2012.20485.x, S2CID 118573795
- ^ Agnew, Matthew T.; Maddison, Sarah T.; Thilliez, Elodie; Horner, Jonathan (2017), "Stable habitable zones of single Jovian planet systems", Monthly Notices of the Royal Astronomical Society, 471 (4): 4494–4507, arXiv:1706.05805, Bibcode:2017MNRAS.471.4494A, doi:10.1093/mnras/stx1449, S2CID 119227856
- ^ Adibekyan, Vardan (2019), "Heavy Metal Rules. I. Exoplanet Incidence and Metallicity", Geosciences, 9 (3): 105, arXiv:1902.04493, Bibcode:2019Geosc...9..105A, doi:10.3390/geosciences9030105, S2CID 119089419
- ^ Wittenmyer, Robert A.; Wang, Songhu; Horner, Jonathan; Tinney, C. G.; Butler, R. P.; Jones, H. R. A.; O'Toole, S. J.; Bailey, J.; Carter, B. D.; Salter, G. S.; Wright, D.; Zhou, Ji-Lin (2013), "Forever alone? Testing single eccentric planetary systems for multiple companions", The Astrophysical Journal Supplement Series, 208 (1): 2, arXiv:1307.0894, Bibcode:2013ApJS..208....2W, doi:10.1088/0067-0049/208/1/2, S2CID 14109907
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