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Kepler-445

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(Redirected from Kepler-445d)
Kepler-445
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus[1]
Right ascension 19h 54m 56.65923s[2]
Declination +46° 29′ 54.7936″[2]
Apparent magnitude (V) 18.19[3]
Characteristics
Evolutionary stage Main sequence
Spectral type M4V[4]
Apparent magnitude (G) 16.685±0.003[2]
Apparent magnitude (J) 13.542±0.029[4]
Apparent magnitude (H) 12.929±0.035[4]
Apparent magnitude (K) 12.610±0.028[4]
Astrometry
Proper motion (μ) RA: 41.465 mas/yr[2]
Dec.: 132.351 mas/yr[2]
Parallax (π)8.1366 ± 0.0457 mas[2]
Distance401 ± 2 ly
(122.9 ± 0.7 pc)
Details[5]
Mass0.334+0.080
−0.059
 M
Radius0.347+0.068
−0.049
 R
Luminosity (bolometric)0.0115 L
Temperature3219+89
−63
 K
Metallicity [Fe/H]+0.27 dex
Other designations
Kepler-445, KOI-2704, KIC 9730163, TIC 268060194, 2MASS J19545665+4629548[4]
Database references
SIMBADdata

Kepler-445 is a red dwarf star located 401 light-years (123 parsecs) away in the constellation Cygnus. It hosts three known exoplanets, discovered by the transit method using data from the Kepler space telescope and confirmed in 2015.[6] None of the planets orbit within the habitable zone.[7]

Planetary system

[edit]

Kepler-445b, c, and d orbit Kepler-445 every 3, 5, and 8 days,[3] and have equilibrium temperatures of 401 K (128 °C; 262 °F), 341 K (68 °C; 154 °F), and 305 K (32 °C; 89 °F), respectively.[8] With a radius of 2.72 times that of Earth, Kepler-445c is likely a mini-Neptune with a volatile-rich composition, and has been compared to GJ 1214 b.[6] Kepler-445d is only slightly larger than the Earth, with a radius of 1.33 R🜨.

The Kepler-445 planetary system[5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 0.023656 2.98416640+0.00000891
−0.00000936
0.02+0.16
−0.02
89.74+0.18
−0.28
[6]°
1.74+0.29
−0.28
 R🜨
c 0.033427 4.87122714+0.00000636
−0.00000638
0.01+0.16
−0.01
89.91+0.07
−0.10
[6]°
2.72+0.44
−0.43
 R🜨
d 0.047121 8.15272856+0.00006453
−0.00007041
0.01+0.16
−0.01
89.61+0.27
−0.25
[6]°
1.33+0.25
−0.23
 R🜨

References

[edit]
  1. ^ "Finding the constellation which contains given sky coordinates". djm.cc. 2 August 2008.
  2. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ^ a b "Kepler-445". NASA Exoplanet Archive. Retrieved 24 May 2023.
  4. ^ a b c d e "Kepler-445". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 24 May 2023.
  5. ^ a b Mann, Andrew W.; Dupuy, Trent; Muirhead, Philip S.; Johnson, Marshall C.; Liu, Michael C.; Ansdell, Megan; Dalba, Paul A.; Swift, Jonathan J.; Hadden, Sam (2017), "The Gold Standard: Accurate Stellar and Planetary Parameters for Eight Kepler M Dwarf Systems Enabled by Parallaxes", The Astronomical Journal, 153 (6): 267, arXiv:1705.01545, Bibcode:2017AJ....153..267M, doi:10.3847/1538-3881/aa7140, S2CID 119325474
  6. ^ a b c d e f Muirhead, Philip S.; Mann, Andrew W.; et al. (March 2015). "Kepler-445, Kepler-446 and the Occurrence of Compact Multiples Orbiting Mid-M Dwarf Stars". The Astrophysical Journal. 801 (1): 18. arXiv:1501.01305. Bibcode:2015ApJ...801...18M. doi:10.1088/0004-637X/801/1/18. S2CID 5541362.
  7. ^ "[...] all of the planets are likely too hot to be located within their host stars’ habitable zones [...]"[6]: 8 
  8. ^ "Kepler Objects of Interest".