| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus [1] |
| Right ascension | 19h 28m 32.8905s [2] |
| Declination | +42° 25′ 45.959″ [2] |
| Apparent magnitude (V) | 15.306 [3] |
| Characteristics | |
| Spectral type | M0V [4] |
| Astrometry | |
| Proper motion (μ) |
RA: −0.488±0.042
[2]
mas/
yr Dec.: 11.692±0.042 [2] mas/ yr |
| Parallax (π) | 2.2527 ± 0.0241 mas [2] |
| Distance | 1,450 ± 20
ly (444 ± 5 pc) |
| Details | |
| Mass | 0.75 [3] M☉ |
| Radius | 0.70 [3] R☉ |
| Luminosity | [3] L☉ |
| Temperature | 4590 [3] K |
| Metallicity [Fe/H] | 0.34 [3] dex |
| Rotation | 17.951±0.016 days [5] |
| Rotational velocity (v sin i) | 0.6 [3] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
| KIC | data |
Kepler-28 is a star in the northern constellation of Cygnus., It is orbited by two exoplanets. It is located at the celestial coordinates: Right Ascension 19h 28m 32.8905s, Declination +42° 25′ 45.959″. [2] With an apparent visual magnitude of 15.036, [3] this star is too faint to be seen with the naked eye.
Planetary system
The two warm sub-Neptune gas giant [6] planets of Kepler-28 were discovered in 2011 and were confirmed in early 2012. [7]
| Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 8.8+3.8 −3.1 M🜨 |
0.062 | 5.9123 | — | — | 2.93±0.46 R🜨 |
| c | 10.9+6.1 −4.5 M🜨 |
0.081 | 8.9858 | — | — | 2.77±0.44 R🜨 |
References
- ^ "Cygnus – constellation boundary", The Constellations, International Astronomical Union, retrieved 2011-12-15
- ^ a b c d e f 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 d e f g h Kepler-28b, NASA Ames Research Center, archived from the original on 2012-05-03, retrieved 2011-12-06
- ^ "Kepler-28". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 10 January 2017.
- ^ McQuillan, A.; Mazeh, T.; Aigrain, S. (2013). "Stellar Rotation Periods of The Kepler objects of Interest: A Dearth of Close-In Planets Around Fast Rotators". The Astrophysical Journal Letters. 775 (1). L11. arXiv: 1308.1845. Bibcode: 2013ApJ...775L..11M. doi: 10.1088/2041-8205/775/1/L11.
- ^ a b Cubillos, Patricio; Erkaev, Nikolai V.; Juvan, Ines; Fossati, Luca; Johnstone, Colin P.; Lammer, Helmut; Lendl, Monika; Odert, Petra; Kislyakova, Kristina G. (2016), "An overabundance of low-density Neptune-like planets", Monthly Notices of the Royal Astronomical Society, 466 (2): 1868–1879, arXiv: 1611.09236, doi: 10.1093/mnras/stw3103, S2CID 119408956
- ^ Steffen, Jason H.; Fabrycky, Daniel C.; Ford, Eric B.; Carter, Joshua A.; Desert, Jean-Michel; Fressin, Francois; Holman, Matthew J.; Lissauer, Jack J.; Moorhead, Althea V.; Rowe, Jason F.; Ragozzine, Darin; Welsh, William F.; Batalha, Natalie M.; Borucki, William J.; Buchhave, Lars A.; Bryson, Steve; Caldwell, Douglas A.; Charbonneau, David; Ciardi, David R.; Cochran, William D.; Endl, Michael; Everett, Mark E.; Gautier III, Thomas N.; Gilliland, Ron L.; Girouard, Forrest R.; Jenkins, Jon M.; Horch, Elliott; Howell, Steve B.; Isaacson, Howard; et al. (2012), Transit Timing Observations from Kepler: III. Confirmation of 4 Multiple Planet Systems by a Fourier-Domain Study of Anti-correlated Transit Timing Variations, arXiv: 1201.5412, Bibcode: 2012MNRAS.421.2342S, doi: 10.1111/j.1365-2966.2012.20467.x, S2CID 11898578
- ^ Schneider, Jean, "Star: Kepler-28", Extrasolar Planets Encyclopaedia, archived from the original on 2012-04-26, retrieved 2011-12-06