| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | |
| Right ascension | 19 36 05.5270 |
| Declination | +45° 51′ 11.108″ |
| Apparent magnitude (V) | 14.0 |
| Characteristics | |
| Spectral type | G5 |
| Astrometry | |
| Proper motion (μ) | RA: −1.007(25) mas/yr Dec.: −7.439(23) mas/yr |
| Parallax (π) | 0.6013 ± 0.0200 mas |
| Distance | 5,400 ± 200 ly (1,660 ± 60 pc) |
| Details | |
| Mass | 1.21 ± 0.17 M☉ |
| Radius | 1.22 ± 0.24 R☉ |
| Luminosity | 0.79 ± 0.04 L☉ |
| Temperature | 6340 ± 200 K |
| Metallicity | –0.076 ± 0.400 dex |
| Other designations | |
| KOI-935, KIC 9347899, 2MASS J19360552+4551110, Gaia DR2 2128013019361703936 | |
| Database references | |
| SIMBAD | data |
| KIC | data |
Kepler-31 is a star in the northern constellation of Cygnus, the swan. It is orbited by three known exoplanets. It is located at the celestial coordinates: Right Ascension 19 36 05.5270, Declination +45° 51′ 11.108″. With an apparent visual magnitude of 14.0, this star is too faint to be seen with the naked eye.
Planetary system
The three gas giant planets orbiting Kepler-31 were discovered in early 2011, albeit with large false alarm probability, and were confirmed in 2012. The planets form a resonant chain, with orbital periods ratio 1:2:4, although 20% probability exists that these period ratios may be coincidental.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| .04(unconfirmed) | — | 0.0937 | 9.61730282±3.35e-5 | — | — | 0.173 RJ |
| b | <6.8 MJ | 0.16 | 20.8613 | — | — | 0.38±0.07 RJ |
| c | <4.7 MJ | 0.26 | 42.6318 | — | — | 0.38±0.07 RJ |
| d | — | 0.39 | 87.648901±0.000801 | — | — | 0.407±0.099 RJ |
References
- "Cygnus – constellation boundary", The Constellations, International Astronomical Union, retrieved 2011-12-15
- ^ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ Kepler-31b, NASA Ames Research Center, archived from the original on 2012-05-03, retrieved 2011-12-06
- ^ Schneider, Jean, "Star: Kepler-23", Extrasolar Planets Encyclopaedia, archived from the original on 2012-05-05, retrieved 2011-12-06
- Lissauer, Jack J.; Ragozzine, Darin; Fabrycky, Daniel C.; Steffen, Jason H.; Ford, Eric B.; Jenkins, Jon M.; Shporer, Avi; Holman, Matthew J.; Rowe, Jason F.; Quintana, Elisa V.; Batalha, Natalie M.; Borucki, William J.; Bryson, Stephen T.; Caldwell, Douglas A.; Carter, Joshua A.; Ciardi, David; Dunham, Edward W.; Fortney, Jonathan J.; Gautier, Iii, Thomas N.; Howell, Steve B.; Koch, David G.; Latham, David W.; Marcy, Geoffrey W.; Morehead, Robert C.; Sasselov, Dimitar (2011), "Architecture and Dynamics of Kepler 'S Candidate Multiple Transiting Planet Systems", The Astrophysical Journal Supplement Series, 197 (1): 8, arXiv:1102.0543, Bibcode:2011ApJS..197....8L, doi:10.1088/0067-0049/197/1/8, S2CID 43095783
- Transit Timing Observations from Kepler: IV. Confirmation of 4 Multiple Planet Systems by Simple Physical Models
- Pichierri, Gabriele; Batygin, Konstantin; Morbidelli, Alessandro (2019), "The role of dissipative evolution for three-planet, near-resonant extrasolar systems", Astronomy & Astrophysics, 625: A7, arXiv:1903.09474, Bibcode:2019A&A...625A...7P, doi:10.1051/0004-6361/201935259, S2CID 85459759
- Planet Kepler-31 d at exoplanets.eu