Astronomy:Kepler-71

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Kepler-71
Observation data
Equinox J2000.0]] (ICRS)
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

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

Star characteristics

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

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

  1. "VARIABLE STAR TYPE DESIGNATIONS IN VSX". https://www.aavso.org/vsx/index.php?view=about.vartypes. Retrieved 2020-05-23. ]
  2. 2.0 2.1 2.2 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. doi:10.1017/S1743921317004057. 
  3. 3.0 3.1 Howell, Steve B.; Rowe, Jason F.; Sherry, William; von Braun, Kaspar; Ciardi, David R.; Bryson, Stephen T.; Feldmeier, John J.; Horch, Elliott et al. (2010). "Keplerobservations of Three Pre-Launch Exoplanet Candidates: Discovery of Two Eclipsing Binaries and a New Exoplanet". The Astrophysical Journal 725 (2): 1633–1643. doi:10.1088/0004-637X/725/2/1633. Bibcode2010ApJ...725.1633H. 
  4. 4.0 4.1 4.2 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". Monthly Notices of the Royal Astronomical Society 484 (1): 618–630. doi:10.1093/mnras/sty3474. Bibcode2019MNRAS.484..618Z. http://eprints.usq.edu.au/37370/2/Zaleski_pub_2019.pdf. 
  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. doi:10.3847/1538-4357/ab67c1. Bibcode2020ApJ...890..121S.