Article · Wikipedia archive · Last revised Jun 28, 2026

Kepler-36

Kepler-36 is a star in the constellation of Cygnus with two known planets. It has an anomalously large radius, meaning that it is a subgiant.

Last revised
Jun 28, 2026
Read time
≈ 2 min
Length
508 w
Citations
23
Source
Kepler-36
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus1
Right ascension 19h 25m 00.0428s2
Declination +49° 13′ 54.631″2
Apparent magnitude (V) 12.13
Characteristics
Evolutionary stage subgiant2
Spectral type G1IV4
Astrometry
Proper motion (μ) RA: 1.151(11) mas/yr2
Dec.: −8.064(11) mas/yr2
Parallax (π)1.8528±0.0087 mas2
Distance1,760 ± 8 ly
(540 ± 3 pc)
Details
Mass1.071±0.0435 M
Radius1.626±0.0195 R
Luminosity3.22 L
Surface gravity (log g)4.1±0.16 cgs
Temperature5911±665 K
Metallicity [Fe/H]−0.2±0.065 dex
Rotation17.20±0.25
Rotational velocity (v sin i)4.9±1.05 km/s
Other designations
KOI-277, KIC 11401755, 2MASS J19250004+4913545, Gaia DR2 21299314566911765767
Database references
SIMBADdata
KICdata

Kepler-36 is a star in the constellation of Cygnus with two known planets. It has an anomalously large radius, meaning that it is a subgiant.

Planetary system

Orbit diagram of the Kepler-36 planetary system source ↗

On June 21, 2012, the discovery of two planets orbiting the star was announced. The planets, a super-Earth and a mini-Neptune, are unusual in that they have very close orbits; their semi-major axes differ by only 0.013 AU. The outer planet orbits only 11% farther than the inner one. Coupled with masses significantly higher than Earth, their gravitational influence to each other is significant, meaning that their interaction causes extreme transit timing variations for both. Kepler-36b and c have estimated densities of 6.8 and 0.86 g/cm3, respectively.5 The two planets are close to a 7:6 orbital resonance.5 The large difference in densities, despite the close proximity of the planets' orbits, is likely due to the large difference in mass.8 The innermost and less massive planet likely lost most, or all, of the hydrogen/helium envelope acquired during formation.

The Kepler-36 planetary system56
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination
(°)
Radius
b 3.83+0.11
−0.10
 M🜨
0.1153 13.86821±0.00049 <0.04 90.0 1.498+0.061
−0.049
 R🜨
c 7.13±0.18 M🜨 0.1283 16.21865±0.00010 <0.04 90.0 3.679+0.096
−0.091
 R🜨
References

References

  1. 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.
  2. 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.
  3. Zacharias, N.; Finch, C. T.; Girard, T. M.; Henden, A.; Bartlett, J. L.; Monet, D. G.; Zacharias, M. I. (2012). "VizieR Online Data Catalog: UCAC4 Catalogue (Zacharias+, 2012)". Vizier Online Data Catalog. Bibcode:2012yCat.1322....0Z.
  4. Shevchenko, Ivan I. (2020). "Multiplanet Systems of Single Stars". Dynamical Chaos in Planetary Systems. Astrophysics and Space Science Library. Vol. 463. pp. 291–303. doi:10.1007/978-3-030-52144-8_13. ISBN 978-3-030-52143-1.
  5. Carter, J. A.; et al. (2012). "Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities". Science. 337 (6094): 556–559. arXiv:1206.4718. Bibcode:2012Sci...337..556C. doi:10.1126/science.1223269. PMID 22722249. S2CID 40245894.
  6. Vissapragada, Shreyas; et al. (2020). "Diffuser-assisted Infrared Transit Photometry for Four Dynamically Interacting Kepler Systems". The Astronomical Journal. 159 (3). 108. arXiv:1907.04445. Bibcode:2020AJ....159..108V. doi:10.3847/1538-3881/ab65c8. S2CID 195874295.
  7. "Kepler-36". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-08-07.
  8. Bodenheimer, P.; Stevenson, D.; Lissauer, J.; D'Angelo, G. (2018). "New Formation Models for the Kepler-36 System". The Astrophysical Journal. 868 (2): id. 138 (17 pp.). arXiv:1810.07160. Bibcode:2018ApJ...868..138B. doi:10.3847/1538-4357/aae928. S2CID 59055335.
External links