| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Lyra1 |
| Right ascension | 19h 06m 19.95772s2 |
| Declination | +39° 04′ 37.8616″2 |
| Apparent magnitude (V) | 13.5443 |
| Characteristics | |
| Evolutionary stage | subgiant2 |
| Spectral type | G1V-IV |
| Astrometry | |
| Radial velocity (Rv) | −62.35±1.852 km/s |
| Proper motion (μ) | RA: +5.818 mas/yr2 Dec.: +17.290 mas/yr2 |
| Parallax (π) | 1.0406±0.0106 mas2 |
| Distance | 3,130 ± 30 ly (961 ± 10 pc) |
| Absolute magnitude (MV) | 3.39 |
| Details3 | |
| Mass | 1.263+0.031 −0.0764 M☉ |
| Radius | 1.714+0.029 −0.0264 R☉ |
| Luminosity | 3.70 L☉ |
| Temperature | 5914 K |
| Metallicity [Fe/H] | 0.100 dex |
| Age | 4.07 Gyr |
| Other designations | |
| Kepler-277, KOI-1215, KIC 3939150, 2MASS J19061996+39043795 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
Kepler-277 is a large yellow star about 961 ± 10 parsecs (3,134 ± 33 ly) away in the constellation of Lyra. It is 1.69 R☉ and 1.12 M☉, with a temperature of 5946 K, a metallicity of -0.315 [Fe/H], and an unknown age.3 For comparison, the Sun has a temperature of 5778 K, a metallicity of 0.00 [Fe/H], and an age of about 4.5 billion years. The large radius in comparison to its mass and temperature suggest that Kepler-277 could be a subgiant star.
Planetary system
Kepler-277 hosts two exoplanets, detected in 2014 via the transit method.3 Named Kepler-277b and Kepler-277c, they are mega-Earths, notable for their unusually high estimated masses and densities.6 A 2025 study speculated that additional, undetected non-transiting planets may bias the transit-timing variation analysis used to estimate the planets' masses.4
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b | 33.6+15.1 −8.2 M🜨 |
0.142 | 17.324161(44) | — | — | 2.92+0.73 −0.63 R🜨 |
| c | 40.4+9.4 −7.0 M🜨 |
0.218 | 33.00672(10) | — | — | 3.36+0.83 −0.72 R🜨 |
References
References
- Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
- 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-277". NASA Exoplanet Archive. Retrieved 21 October 2023.
- Ofir, Aviv; Yoffe, Gideon; Aharonson, Oded (February 2025). "Planetary Mass Determinations from a Simplified Photodynamical Model—Application to the Complete Kepler Dataset". The Astronomical Journal. 169 (2): 90. arXiv:2410.11401. Bibcode:2025AJ....169...90O. doi:10.3847/1538-3881/ad91a7.
- "Kepler-277". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 21 October 2023.
- Futó, P.; et al. (March 2020). Kepler-277 b: A Supermassive Terrestrial Exoplanet in the Kepler-277 Planetary System (PDF). 51st Lunar and Planetary Science Conference. Lunar and Planetary Institute. Bibcode:2020LPI....51.1055F.