Kepler-18

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Coordinates: Sky map 19h 63m 19.06s, +46° 44′ 47.94″

Kepler-18
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus
Right ascension  19h 52m 19.0688s[1]
Declination +44° 44′ 46.808″[1]
Apparent magnitude (V) 14.0
Astrometry
Proper motion (μ) RA: −1.432±0.031[1] mas/yr
Dec.: −20.313±0.028[1] mas/yr
Parallax (π)2.2804 ± 0.0168[1] mas
Distance1,430 ± 10 ly
(439 ± 3 pc)
Details[2]
Mass0.972 ± 0.042 M
Radius1.108 ± 0.051 R
Luminosity0.93 L
Surface gravity (log g)4.32 ± 0.12 cgs
Temperature5383 ± 44 K
Metallicity [Fe/H]0.19 ± 0.06 dex
Rotational velocity (v sin i)<4 km/s
Age10.0 ± 2.3 Gyr
Other designations
KOI-137, KIC 8644288[3]
Database references
SIMBADdata
Extrasolar Planets
Encyclopaedia
data

Kepler-18 is a star with almost the same mass as the Sun in the Cygnus constellation with 3 confirmed planets, announced in 2011.

Planetary system[edit]

The Kepler-18 planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 6.9 ± 3.4 M 0.0447 ± 0.0006 3.504725 ± 0.000028 84.92 ± 0.26° 2.00 ± 0.10 R
c 17.3 ± 1.9 M 0.0752 ± 0.0011 7.64159 ± 0.00003 87.68 ± 0.22° 5.49 ± 0.26 R
d 16.4 ± 1.4 M 0.1172 ± 0.0017 14.85888 ± 0.00004 88.07 ± 0.1° 6.98 ± 0.33 R

References[edit]

  1. ^ a b c d e 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 Data Release 2 catalog entry
  2. ^ a b Cochran, William D.; et al. (2011). "Kepler 18-b, c, and d: A System Of Three Planets Confirmed by Transit Timing Variations, Lightcurve Validation, Spitzer Photometry and Radial Velocity Measurements". The Astrophysical Journal Supplement Series. 197: 7. arXiv:1110.0820. Bibcode:2011ApJS..197....7C. doi:10.1088/0067-0049/197/1/7.
  3. ^ "Kepler-18". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 25 January 2018.

External links[edit]