Astronomy:GJ 3512
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 08h 41m 20.12866s[1] |
| Declination | +59° 29′ 50.4441″[1] |
| Apparent magnitude (V) | +15.05[2] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | dM5.5[3] |
| Astrometry | |
| Radial velocity (Rv) | +7.13±2.45[1] km/s |
| Proper motion (μ) | RA: −260.276[1] mas/yr Dec.: −1,279.562[1] mas/yr |
| Parallax (π) | 105.2935 ± 0.0313[1] mas |
| Distance | 30.976 ± 0.009 ly (9.497 ± 0.003 pc) |
| Details[3] | |
| Mass | 0.1254±0.0031 M☉ |
| Radius | 0.1636±0.0023 R☉ |
| Luminosity | 0.001574±0.000018 L☉ |
| Surface gravity (log g) | 5.240±0.044 cgs |
| Temperature | 3,081±51 K |
| Metallicity [Fe/H] | −0.07±0.16 dex |
| Rotation | 87±5 d[4] |
| Rotational velocity (v sin i) | 2.0[5] km/s |
| Age | 3–8[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
GJ 3512 is a nearby star in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye but can be observed using a telescope, having an apparent visual magnitude of +15.05.[2] The star is located at a distance of 31 light-years from the Sun based on parallax.[1] It has a high proper motion,[6] traversing the celestial sphere at the rate of 1.311″ yr−1.[8] The measurement of the star's radial velocity is poorly constrained, but it appears to be drifting further away at a rate of ~8 km/s.[9]
The stellar classification of GJ 3512 is dM5.5,[3] which determines this to be a small red dwarf star that is generating energy through core hydrogen fusion. It displays a moderate amount of magnetic activity with a Sun-like cycle lasting 14 years. A low-level variability lasting ~87 d matches the approximate rotation period.[4] The star has 12.5% of the mass of the Sun and 16% of the Sun's radius. It is radiating 1.6% of the luminosity of the Sun from its photosphere at an effective temperature of 3,081 K.[3]
Planetary system
A gas giant planet in an eccentric orbit around GJ 3512 was discovered in 2019 utilizing the radial velocity method. The star's mass is only 250 times that of the gas giant, calling into question traditional models of planetary formation.[6][10] If the star was born in an open cluster, this planet may instead have formed around a higher-mass star then been swapped into this system during an interaction.[11] The eccentric orbit of this object may have been caused by the ejection of another exoplanet from the system.[6] A second gas giant planet on a wider, circular orbit is suspected;[6] a 2020 study provided stronger evidence for this planet,[4] and it is now considered confirmed by most sources.[12][13][14]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥0.46+0.02 −0.01 MJ |
0.337±0.001 | 203.69+0.09 −0.02 |
0.44±0.01 | — | — |
| c | ≥0.20±0.01 MJ | 1.292±0.003 | 1,599.6+1.1 −0.8 |
0.0183±0.0001 | — | — |
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 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.
- ↑ 2.0 2.1 Weis, Edward W. (1996). "Photometry of Stars with Large Proper Motion". The Astronomical Journal 112: 2300. doi:10.1086/118183. Bibcode: 1996AJ....112.2300W.
- ↑ 3.0 3.1 3.2 3.3 Schweitzer, A. et al. (May 2019). "The CARMENES search for exoplanets around M dwarfs. Different roads to radii and masses of the target stars". Astronomy & Astrophysics 625: 16. doi:10.1051/0004-6361/201834965. A68. Bibcode: 2019A&A...625A..68S.
- ↑ 4.0 4.1 4.2 4.3 Lopez-Santiago, J. et al. (2020). "A likely magnetic activity cycle for the exoplanet host M dwarf GJ 3512". The Astronomical Journal 160 (6): 273. doi:10.3847/1538-3881/abc171. Bibcode: 2020AJ....160..273L.
- ↑ Reiners, Ansgar et al. (2018). "The CARMENES search for exoplanets around M dwarfs. High-resolution optical and near-infrared spectroscopy of 324 survey stars". Astronomy and Astrophysics 612: A49. doi:10.1051/0004-6361/201732054. Bibcode: 2018A&A...612A..49R.
- ↑ 6.0 6.1 6.2 6.3 6.4 Morales, J. C. et al. (2019). "A giant exoplanet orbiting a very-low-mass star challenges planet formation models". Science 365 (6460): 1441–1445. doi:10.1126/science.aax3198. ISSN 0036-8075. PMID 31604272. Bibcode: 2019Sci...365.1441M.
- ↑ "G 234-45". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=G+234-45.
- ↑ Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal 129 (3): 1483–1522. doi:10.1086/427854. Bibcode: 2005AJ....129.1483L.
- ↑ Newton, Elisabeth R. et al. (2014). "Near-infrared Metallicities, Radial Velocities, and Spectral Types for 447 Nearby M Dwarfs". The Astronomical Journal 147 (1): 20. doi:10.1088/0004-6256/147/1/20. Bibcode: 2014AJ....147...20N.
- ↑ Choi, Charles Q. (26 September 2019). "Surprise! Giant Planet Found Circling Tiny Red Dwarf Star". https://www.space.com/gas-giant-alien-planet-red-dwarf.html.
- ↑ Wang, Yi-Han et al. (March 2020). "Giant Planet Swaps during Close Stellar Encounters". The Astrophysical Journal Letters 891 (1): 6. doi:10.3847/2041-8213/ab77d0. L14. Bibcode: 2020ApJ...891L..14W.
- ↑ "Planet GJ 3512 c". Extrasolar Planets Encyclopaedia. 1995. https://exoplanet.eu/catalog/gj_3512_c--7193/.
- ↑ "GJ 3512". https://exoplanetarchive.ipac.caltech.edu/overview/GJ%203512. Retrieved 28 August 2022.
- ↑ Reylé, Céline; Jardine, Kevin; Fouqué, Pascal; Caballero, Jose A.; Smart, Richard L.; Sozzetti, Alessandro (30 April 2021). "The 10 parsec sample in the Gaia era". Astronomy & Astrophysics 650: A201. doi:10.1051/0004-6361/202140985. Bibcode: 2021A&A...650A.201R. Data available at https://gruze.org/10pc/
External links
- "Planet GJ 3512 b". Extrasolar Planets Encyclopaedia. 1995. https://exoplanet.eu/catalog/gj_3512_b--7192/.
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