Gliese 42
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sculptor[1] |
| Right ascension | 00h 53m 01.1349s[2] |
| Declination | −30° 21′ 24.891″[2] |
| Apparent magnitude (V) | +7.17[3] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | K2.5 V (k)[4] |
| B−V color index | 0.936[5] |
| Astrometry | |
| Radial velocity (Rv) | −13.021±0.0064[6] km/s |
| Proper motion (μ) | RA: +620.243[2] mas/yr Dec.: +31.770[2] mas/yr |
| Parallax (π) | 71.7259±0.0267 mas[2] |
| Distance | 45.47 ± 0.02 ly (13.942 ± 0.005 pc) |
| Absolute magnitude (MV) | +6.39[1] |
| Details | |
| Mass | 0.81[7] M☉ |
| Radius | 0.74[7] R☉ |
| Luminosity | 0.29[7] L☉ |
| Surface gravity (log g) | 4.60[7] cgs |
| Temperature | 4,921[7] K |
| Metallicity [Fe/H] | −0.21[4] dex |
| Rotational velocity (v sin i) | 1.8[8] km/s |
| Age | 6.67±4.74[9] Gyr |
| Other designations | |
| BD−31°325, GJ 42, HD 5133, HIP 4148, SAO 192793, LTT 498, 2MASS J00530108-3021249[10] | |
| Database references | |
| SIMBAD | data |
Gliese 42 is a star in the southern constellation of Sculptor. It is too faint to be seen with the naked eye, having an apparent visual magnitude of +7.2. The annual parallax shift of 71.7 mas provides a distance estimate of 45 light years. It has a relatively high proper motion, advancing 0.62 arcseconds across the sky per annum,[11] and is moving closer to the Sun with a radial velocity of −13 km/s.[6]
The spectrum of the star matches a stellar classification of K2.5 V (k),[4] indicating it is an ordinary K-type main-sequence star that is generating energy through hydrogen fusion at its core. It is radiating 29% of the Sun's luminosity from its photosphere at an effective temperature of 4,921 K.[7] The star has 74% of the Sun's radius.[7]
Debris disk
An infrared excess has been detected around this star,[12] most likely indicating the presence of a circumstellar disk at a radius of 45.7 astronomical units (6.84×109 km; 4.25×109 mi). The temperature of this dust was initially estimated as 30 K (−243.2 °C; −405.7 °F)[13] according to measurement by Herschel Space Observatory. Later that measurement was deemed questionable,[14] and fixed temperature of 62 K (−211.2 °C; −348.1 °F) was obtained in 2020.[15]
References
- ^ a b 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.
- ^ a b c d e f 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.
- ^ 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. Bibcode:2010MNRAS.403.1949K. doi:10.1111/j.1365-2966.2009.16182.x.
- ^ a b c Gray, R. O.; et al. (July 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, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b Soubiran, C.; et al. (April 2013). "The catalogue of radial velocity standard stars for Gaia. I. Pre-launch release". Astronomy & Astrophysics. 552: 11. arXiv:1302.1905. Bibcode:2013A&A...552A..64S. doi:10.1051/0004-6361/201220927. S2CID 56094559. A64.
- ^ a b c d e f g Stassun, Keivan G.; et al. (2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467.
- ^ Andretta, Vincenzo; Giampapa, Mark S.; Covino, Elvira; Reiners, Ansgar; Beeck, Benjamin (2017). "Estimates of Active Region Area Coverage through Simultaneous Measurements of the He I λλ 5876 and 10830 Lines". The Astrophysical Journal. 839 (2): 97. arXiv:1703.10060. Bibcode:2017ApJ...839...97A. doi:10.3847/1538-4357/aa6a14.
- ^ Pace, G. (March 2013), "Chromospheric activity as age indicator. An L-shaped chromospheric-activity versus age diagram", Astronomy & Astrophysics, 551: 4, arXiv:1301.5651, Bibcode:2013A&A...551L...8P, doi:10.1051/0004-6361/201220364, S2CID 56420519, L8.
- ^ "HD 5133". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-01-01.
- ^ Bakos, Gáspár Á.; et al. (July 2002), "Revised Coordinates and Proper Motions of the Stars in the Luyten Half-Second Catalog", The Astrophysical Journal Supplement Series, 141 (1): 187–193, arXiv:astro-ph/0202164, Bibcode:2002ApJS..141..187B, doi:10.1086/340115, S2CID 36667868.
- ^ Eiroa, C.; et al. (July 2013). "DUst around NEarby Stars. The survey observational results". Astronomy & Astrophysics. 555: A11. arXiv:1305.0155. Bibcode:2013A&A...555A..11E. doi:10.1051/0004-6361/201321050. S2CID 377244.
- ^ Cotten, Tara H.; Song, Inseok (July 2016), "A Comprehensive Census of Nearby Infrared Excess Stars", The Astrophysical Journal Supplement Series, 225 (1): 24, arXiv:1606.01134, Bibcode:2016ApJS..225...15C, doi:10.3847/0067-0049/225/1/15, S2CID 118438871, 15.
- ^ Gáspár, András; Rieke, George H. (2014). "The Herschel Cold Debris Disks: Confusion with the Extragalactic Background at 160 μm". The Astrophysical Journal. 784 (1): 33. arXiv:1308.1954. Bibcode:2014ApJ...784...33G. doi:10.1088/0004-637X/784/1/33.
- ^ Su, Kate Y L.; Kennedy, Grant M.; Yelverton, Ben (2020), "No significant correlation between radial velocity planet presence and debris disc properties", Monthly Notices of the Royal Astronomical Society, 495 (2): 1943–1957, arXiv:2005.03573, doi:10.1093/mnras/staa1316, S2CID 218538179
External links
- University of Heidelberg, The. "ARICNS ARI Data Base for Nearby Stars". Archived from the original on 28 September 2012. Retrieved 8 May 2012.
- University of Strasbourg, The. "SIMBAD star database". Archived from the original on 2 October 2018. Retrieved 8 May 2012.
- University of Hamburg, The. "NEXXUS 2 - The database for Nearby X-ray and extreme UV emitting Stars". Archived from the original on 4 March 2016. Retrieved 8 May 2012.
- Sol Stations, The. "K stars within 100 light-years". Archived from the original on 24 December 2017. Retrieved 8 May 2012.