Kepler-71 is a yellow main sequence star in the constellation of Cygnus.

Kepler-71
Observation data
Epoch J2000      Equinox
Constellation Cygnus
Right ascension 19h 37m 57.7155s
Declination 46° 17′ 08.9428″
Apparent magnitude (V) 15.06
Characteristics
Evolutionary stage main sequence star
Spectral type G8V
V−R color index -0.29
R−I color index 0.46
J−H color index 0.377
J−K color index 0.457
Variable type ROT[1]
Astrometry
Radial velocity (Rv)0±7 km/s
Proper motion (μ) RA: -2.343±0.039 mas/yr
Dec.: -1.073±0.041 mas/yr
Parallax (π)1.0647 ± 0.0204 mas
Distance3,060 ± 60 ly
(940 ± 20 pc)
Details[2][3][4]
Mass0.923 M
Radius0.816 R
Surface gravity (log g)4.54±0.01 cgs
Temperature5545 K
Metallicity [Fe/H]0.22 dex
Rotationperiod 20 days
Age2.5-4 Gyr
Other designations
KOI-217, BOKS 40959, KIC 9595827, 2MASS J19392772+4617090, Gaia DR2 2080095679848047872[5]
Database references
SIMBADdata

Star characteristics edit

Kepler-71 is enriched by heavy elements at 170% of Sun metallicity, young and has a very prominent starspot activity. Starspots are covering about 40% of star surface at transit latitudes, each planetary transit passing over an average six starspots.[2] The bright facula regions are even more extensive.[6] Unlike Sun, the photosphere of Kepler-71 rotates nearly like rigid body, with differential rotation not exceeding 2%.[4]

Planetary system edit

The "Hot Jupiter" class planet Kepler-71b was discovered around Kepler-71 in 2010.[3]

The Kepler-71 planetary system[2][4]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 0.05029+0.00002
−0.00006
3.905079476+0.000008
−0.000009
0 89.8+0.2
−0.4
°
1.1987±0.0044 RJ

References edit

  1. ^ Sebastián Otero; Christopher Watson; Patrick Wils. "VARIABLE STAR TYPE DESIGNATIONS IN VSX". Variable Star Index. Retrieved 2020-05-23.]
  2. ^ a b c Gusmão, Eber A.; Selhorst, Caius L.; Oliveira, Alexandre S. (2016). "Analysis of Kepler-71 Activity Through Planetary Transit". Proceedings of the International Astronomical Union. 12: 140–142. arXiv:1703.00883. doi:10.1017/S1743921317004057. S2CID 119106951.
  3. ^ a b Howell, Steve B.; Rowe, Jason F.; Sherry, William; von Braun, Kaspar; Ciardi, David R.; Bryson, Stephen T.; Feldmeier, John J.; Horch, Elliott; Van Belle, Gerard T. (2010). "Keplerobservations of Three Pre-Launch Exoplanet Candidates: Discovery of Two Eclipsing Binaries and a New Exoplanet". The Astrophysical Journal. 725 (2): 1633–1643. arXiv:1010.4106. Bibcode:2010ApJ...725.1633H. doi:10.1088/0004-637X/725/2/1633. S2CID 37374489.
  4. ^ a b c Zaleski, S. M.; Valio, A.; Marsden, S. C.; Carter, B. D. (2019). "Differential rotation of Kepler-71 via transit photometry mapping of faculae and starspots" (PDF). Monthly Notices of the Royal Astronomical Society. 484 (1): 618–630. Bibcode:2019MNRAS.484..618Z. doi:10.1093/mnras/sty3474.
  5. ^ KOI-217 -- Rotationally variable Star
  6. ^ Schrijver, Carolus J. (2020). "Testing the Solar Activity Paradigm in the Context of Exoplanet Transits". The Astrophysical Journal. 890 (2): 121. arXiv:2001.01093. Bibcode:2020ApJ...890..121S. doi:10.3847/1538-4357/ab67c1. S2CID 209862471.