GJ 2030
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 03h 23m 17.70116s |
| Declination | −07° 47′ 38.7554″ |
| Apparent magnitude (V) | 6.206±0.003 |
| Characteristics | |
| Evolutionary stage | subgiant |
| Spectral type | G5/6V |
| Astrometry | |
| Radial velocity (Rv) | +41.67±0.16 km/s |
| Proper motion (μ) | RA: +1.295 mas/yr Dec.: −219.292 mas/yr |
| Parallax (π) | 26.7913±0.0912 mas |
| Distance | 121.7 ± 0.4 ly (37.3 ± 0.1 pc) |
| Absolute magnitude (MV) | +3.35 |
| Details | |
| Mass | 1.022±0.024 M☉ |
| Radius | 2.429±0.061 R☉ |
| Luminosity | 4.064±0.043 L☉ |
| Surface gravity (log g) | 3.73±0.12 cgs |
| Temperature | 5,259±66 K |
| Metallicity [Fe/H] | −0.45±0.02 dex |
| Age | 6.39 Gyr |
| Other designations | |
| BD−08°643, GJ 2030, HD 21019, HIP 15776, HR 1024, TYC 5295-1155-1 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
GJ 2030 is a star in the constellation Eridanus. At an apparent magnitude of +6.206, it is close to the average threshold for naked eye visibility, and can only be viewed from sufficiently dark skies, far from light pollution. Parallax measurements by the Gaia spacecraft measured a distance of 121.7 light-years, give or take 0.4 light-years.
The spectrum of this star matches a spectral class of G5/6V, with the luminosity class V suggesting it is a main sequence star, but its physical properties suggest it is actually a subgiant. It has 1.02 times the Sun's mass and 2.43 times the Sun's radius. It radiates 4.06 times the Sun's luminosity from its photosphere at an effective temperature of 5,259 K. At this temperature, the star shines with a yellowish color typical of G-type stars.
GJ 2030 is likely a member of the thick disk population, with a substantially lower metallicity than the Sun. Its age is estimated at 6.39 billion years, older than the Solar System.
Planetary system
Two extrasolar planets were discovered around the star in 2022, detected via Doppler spectroscopy (radial velocity method) and astrometry.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b | ≥0.015±0.002 MJ | 0.034+0.001 −0.002 |
0.0065196±0.0000004 | 0.239+0.075 −0.058 |
— | — |
| c | 12.803+2.335 −2.136 MJ |
16.761+1.294 −1.337 |
69.91+6.36 −7.00 |
0.041+0.003 −0.008 |
16.999+2.935 −2.535 |
— |
References
- 1 2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
- 1 2 3 4 5 6 7 8 9 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.
- 1 2 Paunzen, E. (August 2015). "A new catalogue of Strömgren-Crawford uvbyβ photometry". Astronomy and Astrophysics. 580: A23. arXiv:1506.04568. Bibcode:2015A&A...580A..23P. doi:10.1051/0004-6361/201526413. ISSN 0004-6361.
- 1 2 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5". Michigan Spectral Survey. 5: 0. Bibcode:1999MSS...C05....0H.
- 1 2 3 Soubiran, C.; et al. (2024-02-01). "Gaia FGK benchmark stars: Fundamental Teff and log g of the third version". Astronomy and Astrophysics. 682: A145. arXiv:2310.11302. Bibcode:2024A&A...682A.145S. doi:10.1051/0004-6361/202347136. ISSN 0004-6361.
- 1 2 Casagrande, L.; Schönrich, R.; Asplund, M.; Cassisi, S.; Ramírez, I.; Meléndez, J.; Bensby, T.; Feltzing, S. (June 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey". Astronomy and Astrophysics. 530: A138. arXiv:1103.4651. Bibcode:2011A&A...530A.138C. doi:10.1051/0004-6361/201016276. ISSN 0004-6361.
- ↑ "GJ 2030". SIMBAD. Centre de données astronomiques de Strasbourg.
- ↑ "Limiting Magnitude | COSMOS". astronomy.swin.edu.au. Retrieved 2025-06-01.
- ↑ "The Colour of Stars". Australia Telescope, Outreach and Education. Commonwealth Scientific and Industrial Research Organisation. December 21, 2004. Archived from the original on 2013-12-03. Retrieved 2012-01-16.
- ↑ Horch, Elliott P.; van Belle, Gerard T.; Davidson, James W.; Ciastko, Lindsay A.; Everett, Mark E.; Bjorkman, Karen S. (November 2015). "Observations of Binary Stars with the Differential Speckle Survey Instrument. VI. Measures during 2014 at the Discovery Channel Telescope". The Astronomical Journal. 150 (5): 151. arXiv:1509.03498. Bibcode:2015AJ....150..151H. doi:10.1088/0004-6256/150/5/151. ISSN 0004-6256.
- 1 2 Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.
