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]
| 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] |
| Distance | 401 ± 2 ly (122.9 ± 0.7 pc) |
| Details[5] | |
| Mass | 0.334+0.080 −0.059 M☉ |
| Radius | 0.347+0.068 −0.049 R☉ |
| Luminosity (bolometric) | 0.0115 L☉ |
| Temperature | 3219+89 −63 K |
| Metallicity [Fe/H] | +0.27 dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Planetary system
editKepler-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🜨.
| 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- ^ "Finding the constellation which contains given sky coordinates". djm.cc. 2 August 2008.
- ^ 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.
- ^ a b "Kepler-445". NASA Exoplanet Archive. Retrieved 24 May 2023.
- ^ a b c d e "Kepler-445". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 24 May 2023.
- ^ 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
- ^ 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.
- ^ "[...] all of the planets are likely too hot to be located within their host stars’ habitable zones [...]"[6]: 8
- ^ "Kepler Objects of Interest".