Kepler-25

Kepler-25 is a star in the northern constellation of Lyra.[1] It is slightly larger and more massive than the sun with a luminosity 2½ times that of the sun.[5] With an apparent visual magnitude of 10.6,[3] this star is too faint to be seen with the naked eye.

Kepler-25

Observation data Epoch J2000      Equinox J2000
Constellation	Lyra[1]
Right ascension	19^h 06^m 33.2143^s[2]
Declination	+39° 29′ 16.358″[2]
Apparent magnitude (V)	10.623±0.053[3]
Characteristics
Spectral type	F[4]
Apparent magnitude (B)	11.337±0.016[3]
Variable type	Planetary transit variable
Astrometry
Proper motion (μ)	RA: −0.455±0.040[2] mas/yr Dec.: 6.169±0.044[2] mas/yr
Parallax (π)	4.0822 ± 0.0236[2] mas
Distance	799 ± 5 ly (245 ± 1 pc)
Details
Mass	1.159+0.040 −0.051[5] M☉
Radius	1.297±0.015[5] R☉
Luminosity	2.406+0.126 −0.128[5] L☉
Surface gravity (log g)	4.275+0.007 −0.008[5] cgs
Temperature	6270±79[6] K
Metallicity [Fe/H]	−0.05±0.10[6] dex
Rotation	23.147±0.039 days[7]
Rotational velocity (v sin i)	9.5[8] km/s
Age	3.45+0.81 −0.72[5] Gyr
Other designations
Gaia DR2 2100451630105041152, KOI-244, KIC 4349452, TYC 3124-1264-1, 2MASS J19063321+3929164[9]
Database references
SIMBAD	data
KIC	data

Planetary system

In 2011, two candidate planets were found transiting this star by the Kepler space telescope.[10] These planets are very close to yet not lie in the 1:2 orbital resonance to each other, indicating the absence of other planetary objects in the inner part of the planetary systems.[11]These planets were confirmed through transit-timing variation method.[12] A third planet was discovered through follow-up radial velocity measurements and was confirmed in January 2014.[8]

The plane of planetary orbits is well aligned with the equatorial plane of the star, misalignment angle equal to 7±8°[13]

The Kepler-25 planetary system[14][4]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	8.7+2.5 −2.3 M⊕	0.068	6.238297±0.000017	0.0029+0.0023 −0.0017	92.827+0.084 −0.083°	2.748+0.038 −0.035 R⊕
c	15.2+1.3 −1.6 M⊕	0.11	12.7207±0.0001	0.0061+0.0049 −0.0041	92.764+0.042 −0.039°	5.217+0.070 −0.065 R⊕
d	71.9±9.8 M⊕	—	122.4+0.0 −0.7	0.13+0.13 −0.09	—	—

References

1. Roman, Nancy G. (1987). "Identification of a Constellation From a Position". Publications of the Astronomical Society of the Pacific. 99 (617): 695–699. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Vizier query form
2. 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.
3. Henden, A. A.; et al. (2016). "VizieR Online Data Catalog: AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)". VizieR On-line Data Catalog: II/336. Originally Published in: 2015AAS...22533616H. 2336. Bibcode:2016yCat.2336....0H. Vizier catalog entry
4. Schneider, Jean, "Star: Kepler-25", Extrasolar Planets Encyclopaedia, Paris Observatory, archived from the original on 2012-06-16, retrieved 2013-12-18
5. Silva Aguirre, V.; et al. (2015). "Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology". Monthly Notices of the Royal Astronomical Society. 452 (2): 2127–2148. arXiv:1504.07992. Bibcode:2015MNRAS.452.2127S. doi:10.1093/mnras/stv1388.
6. Huber, Daniel; et al. (2013). "Fundamental Properties of Kepler Planet-candidate Host Stars using Asteroseismology". The Astrophysical Journal. 767 (2). 127. arXiv:1302.2624. Bibcode:2013ApJ...767..127H. doi:10.1088/0004-637X/767/2/127.
7. 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.
8. Marcy, Geoffrey W.; et al. (2014). "Masses, Radii, and Orbits of Small Kepler Planets: The Transition from Gaseous to Rocky Planets". The Astrophysical Journal Supplement Series. 210 (2). 20. arXiv:1401.4195. Bibcode:2014ApJS..210...20M. doi:10.1088/0067-0049/210/2/20.
9. "Kepler-25". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-02.
10. Borucki, William J.; et al. (2011). "Characteristics of Planetary Candidates Observed by Kepler. II. Analysis of the First Four Months of Data". The Astrophysical Journal. 736 (1). 19. arXiv:1102.0541. Bibcode:2011ApJ...736...19B. doi:10.1088/0004-637X/736/1/19.
11. Migaszewski, Cezary; Gozdziewski, Krzysztof (2018), A periodic configuration of the Kepler-25 planetary system?, arXiv:1803.10285, doi:10.1093/mnras/sty1972, S2CID 55395774
12. Steffen, Jason H.; et al. (2012). "Transit timing observations from Kepler - III. Confirmation of four multiple planet systems by a Fourier-domain study of anticorrelated transit timing variations". Monthly Notices of the Royal Astronomical Society. 421 (3): 2342–2354. arXiv:1201.5412. Bibcode:2012MNRAS.421.2342S. doi:10.1111/j.1365-2966.2012.20467.x.
13. Albrecht, Simon; Winn, Joshua N.; Marcy, Geoffrey W.; Howard, Andrew W.; Isaacson, Howard; Johnson, John A. (2013), "Low Stellar Obliquities in Compact Multiplanet Systems", The Astrophysical Journal, 771: 11, arXiv:1302.4443, doi:10.1088/0004-637X/771/1/11, S2CID 17247029
14. Mills, Sean M.; et al. (2019). "Long-period Giant Companions to Three Compact, Multiplanet Systems". The Astronomical Journal. 157 (4). 145. arXiv:1903.07186. Bibcode:2019AJ....157..145M. doi:10.3847/1538-3881/ab0899.