Astronomy:Gliese 357
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Short description: Red dwarf with low starspot activity in the Hydra constellation
 Artist concept of the Gliese 357 (GJ357) system. Credit: Jack Madden | |
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Hydra |
| Right ascension | 09h 36m 01.63722s[1] |
| Declination | −21° 39′ 38.8776″[1] |
| Apparent magnitude (V) | 10.906[2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | M2.5V[3] |
| Astrometry | |
| Radial velocity (Rv) | −35.03±0.17[1] km/s |
| Proper motion (μ) | RA: 138.722±0.023[1] mas/yr Dec.: −990.342±0.020[1] mas/yr |
| Parallax (π) | 105.9789 ± 0.0227[1] mas |
| Distance | 30.776 ± 0.007 ly (9.436 ± 0.002 pc) |
| Absolute magnitude (MV) | +11.13[4] |
| Details | |
| Mass | 0.362[5] M☉ |
| Radius | 0.333[4] R☉ |
| Luminosity | 0.014[6] L☉ |
| Surface gravity (log g) | 4.96[5] cgs |
| Temperature | 3,488[5] K |
| Metallicity [Fe/H] | −0.14[5] dex |
| Rotation | 74.3±1.7 d[7] |
| Rotational velocity (v sin i) | 2.5[5] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
GJ 357 (also designated Gliese 357) is an M-type main sequence star with an unusually low starspot activity.[8] It is located 31 light-years from the Solar System.[9] The system is part of the Hydra constellation.[9]
Planetary system
The star has three confirmed exoplanets in its orbit,[10] one of which, Gliese 357 d, is considered to be a "super-Earth" within the circumstellar habitable zone.[11][9][12][13]
Planets b and c are close to 3:7 mean-motion resonance. Presuming resonance chain crosses gap to outermost and cold super-terrestrial d and the resonances are simple, GJ 357 may have much more suitable planet for life at approx. 27.5 day period and almost Earth's flux, and (less likely) Mars-sized planet in 2:1 period ratio with GJ 357 c and 2:3 ratio with hypothetical HZ rocky one.[citation needed]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 1.84±0.31 M⊕ | 0.035±0.002 | 3.93072+0.00008 −0.00006 |
0.047+0.059−0.047 | 89.12+0.37 −0.31° |
1.217+0.084 −0.083 R⊕ |
| c | ≥3.40±0.46 M⊕ | 0.061±0.004 | 9.1247+0.0011 −0.0010 |
0.072±0.053 | — | — |
| d | ≥6.1±1.0 M⊕ | 0.204±0.015 | 55.661±0.055 | 0.033+0.057−0.033 | — | — |
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ Koen, C.; Kilkenny, D.; Van Wyk, F.; Marang, F. (2010). "UBV(RI)C JHK observations of Hipparcos-selected nearby stars". Monthly Notices of the Royal Astronomical Society 403 (4): 1949. doi:10.1111/j.1365-2966.2009.16182.x. Bibcode: 2010MNRAS.403.1949K.
- ↑ Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample". The Astronomical Journal 132 (1): 161–170. doi:10.1086/504637. Bibcode: 2006AJ....132..161G.
- ↑ 4.0 4.1 Houdebine, E. R.; Mullan, D. J.; Paletou, F.; Gebran, M.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2016). "Rotation-Activity Correlations in K and M Dwarfs. I. Stellar Parameters and Compilations of v sin I and P/Sin I for a Large Sample of Late-K and M Dwarfs". The Astrophysical Journal 822 (2): 97. doi:10.3847/0004-637X/822/2/97. Bibcode: 2016ApJ...822...97H.
- ↑ 5.0 5.1 5.2 5.3 5.4 Passegger, V. M.; Reiners, Ansgar; Jeffers, S. V.; Wende-von Berg, S.; Schöfer, P.; Caballero, J. A.; Schweitzer, A.; Amado, P. J. et al. (2018). "The CARMENES search for exoplanets around M dwarfs. Photospheric parameters of target stars from high-resolution spectroscopy". Astronomy and Astrophysics 615: A6. doi:10.1051/0004-6361/201732312. Bibcode: 2018A&A...615A...6P.
- ↑ Morales, J. C.; Ribas, I.; Jordi, C.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2008). "The effect of activity on stellar temperatures and radii". Astronomy and Astrophysics 478 (2): 507. doi:10.1051/0004-6361:20078324. Bibcode: 2008A&A...478..507M.
- ↑ Suárez Mascareño, A.; Rebolo, R.; González Hernández, J. I.; Esposito, M. (2015), "Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators", Monthly Notices of the Royal Astronomical Society 452 (3): 2745–2756, doi:10.1093/mnras/stv1441, Bibcode: 2015MNRAS.452.2745S
- ↑ Modirrousta-Galian, D.; Stelzer, B.; Magaudda, E.; Maldonado, J.; Güdel, M.; Sanz-Forcada, J.; Edwards, B.; Micela, G. (2020), "A Super-Earth Orbiting an Extremely Inactive Host Star", Astronomy & Astrophysics A113: 641, doi:10.1051/0004-6361/202038280
- ↑ 9.0 9.1 9.2 Reddy, Francis; Center, NASA’s Goddard Space Flight (2019-07-31). "TESS Discovers Habitable Zone Planet in GJ 357 System" (in en-US). https://scitechdaily.com/tess-discovers-habitable-zone-planet-in-gj-357-system/.
- ↑ "The Extrasolar Planet Encyclopaedia — Gj 357 b". Extrasolar Planets Encyclopaedia. 1995. https://exoplanet.eu/catalog/gj_357_b--7109/.
- ↑ Falconer, Rebecca, Newly uncovered super-Earth 31 light-years away may be habitable, Axios, August 1, 2019
- ↑ "Potentially habitable 'super-Earth' discovered just 31 light-years away" (in en). 31 July 2019. https://www.nbcnews.com/mach/science/potentially-habitable-super-earth-discovered-just-31-light-years-away-ncna1037491.
- ↑ Garner, Rob (2019-07-30). "NASA's TESS Helps Find Intriguing New World". http://www.nasa.gov/feature/goddard/2019/confirmation-of-toasty-tess-planet-leads-to-surprising-find-of-promising-world.
- ↑ Luque, R. et al. (August 2019). "Planetary system around the nearby M dwarf GJ 357 including a transiting, hot, Earth-sized planet optimal for atmospheric characterization". Astronomy & Astrophysics 628: A39. doi:10.1051/0004-6361/201935801. Bibcode: 2019A&A...628A..39L.
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