Astronomy:Kepler-45

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Short description: M-type star in the constellation Cygnus
Kepler-45
Observation data
Equinox J2000.0]] (ICRS)
Constellation Cygnus[1]
Right ascension  19h 31m 29.4967s[2]
Declination +41° 03′ 51.356″[2]
Apparent magnitude (V) 16.88[3]
Characteristics
Spectral type M1 V[4]
Astrometry
Proper motion (μ) RA: 4.635±0.071[2] mas/yr
Dec.: −21.579±0.083[2] mas/yr
Parallax (π)2.5904 ± 0.0434[2] mas
Distance1,260 ± 20 ly
(386 ± 6 pc)
Details
Mass0.59 ± 0.06[5] M
Radius0.55 ± 0.11[5] R
Temperature3820 ± 90[5] K
Metallicity [Fe/H]0.13 ± 0.13[5] dex
Other designations
Database references
SIMBADdata
KICdata

Kepler-45, formerly known as KOI-254, is a star in the northern constellation of Cygnus. It is located at the celestial coordinates: right ascension  19h 31m 29.495s, declination +41° 03′ 51.37″.[6] With an apparent visual magnitude of 16.88,[4] this star is too faint to be seen with the naked eye.

The star is exhibiting strong starspot activity, with 4.1±2.5% of its surface covered by starspots.[7]

Planetary system

The Kepler-45 planetary system[8]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 0.5505 MJ 0.030 2.455239 11 R

The "Hot Jupiter" class planet Kepler-45b,[9] discovered in February 2011,[10] is unusually massive for the M-class parent star.[11] Its orbit is aligned within 11 degrees of rotational axis of the star.[12]

The planet is strongly suspected to have optically thick rings, because planetary shadow appears to be elongated.[13]

See also

References

  1. "Cygnus – constellation boundary", The Constellations, International Astronomical Union, http://www.iau.org/public/constellations/#cyg, retrieved 2011-12-15 
  2. 2.0 2.1 2.2 2.3 2.4 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  3. "Kepler-45". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=Kepler-45. 
  4. 4.0 4.1 Muirhead, Philip S. et al. (May 2012). "Characterizing the Cool Kepler Objects of Interests. New Effective Temperatures, Metallicities, Masses, and Radii of Low-mass Kepler Planet-candidate Host Stars". The Astrophysical Journal Letters 750 (2): L37. doi:10.1088/2041-8205/750/2/L37. Bibcode2012ApJ...750L..37M. 
  5. 5.0 5.1 5.2 5.3 Kepler-45b, NASA Ames Research Center, http://kepler.nasa.gov/Mission/discoveries/kepler45b/, retrieved 2011-12-06 
  6. "Kepler Discoveries". 2011-12-05. http://kepler.nasa.gov/Mission/discoveries/. 
  7. Activity and differential rotation of the early M dwarf Kepler-45 from transit mapping
  8. Schneider, Jean, Star: Kepler-45, http://exoplanet.eu/star.php?st=Kepler-45, retrieved 2011-12-06 
  9. Kepler-45 b at exoplanet.eu
  10. Ford, Eric B.; Rowe, Jason F.; Fabrycky, Daniel C.; Carter, Joshua A.; Holman, Matthew J.; Lissauer, Jack J.; Ragozzine, Darin; Steffen, Jason H. et al. (2011), "Transit Timing Observations from Kepler : I. Statistical Analysis of the First Four Months", The Astrophysical Journal Supplement Series 197 (1): 2, doi:10.1088/0067-0049/197/1/2, Bibcode2011ApJS..197....2F 
  11. Gaidos, E.; Mann, A. W.; Kraus, A. L.; Ireland, M. (2016). "They are small worlds after all: Revised properties of Kepler M dwarf stars and their planets". Monthly Notices of the Royal Astronomical Society 457 (3): 2877–2899. doi:10.1093/mnras/stw097. Bibcode2016MNRAS.457.2877G. 
  12. Dai, Fei; Winn, Joshua N.; Berta-Thompson, Zachory; Sanchis-Ojeda, Roberto; Albrecht, Simon (2018). "Stellar Obliquity and Magnetic Activity of Planet-hosting Stars and Eclipsing Binaries Based on Transit Chord Correlation". The Astronomical Journal 155 (4): 177. doi:10.3847/1538-3881/aab618. Bibcode2018AJ....155..177D. 
  13. Revealing peculiar exoplanetary shadows from transit light curves

Coordinates: Sky map 19h 31m 29.495s, +41° 03′ 51.37″