V762 Cassiopeiae
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cassiopeia |
Right ascension | 01h 16m 11.902s[1] |
Declination | +71° 44′ 37.83″[1] |
Apparent magnitude (V) | 5.86[2] |
Characteristics | |
Evolutionary stage | Red supergiant[3] |
Spectral type | K5 I[3] |
Astrometry | |
Radial velocity (Rv) | −21.37±0.91[1] km/s |
Proper motion (μ) | RA: -1.658 mas/yr[1] Dec.: 1.791 mas/yr[1] |
Parallax (π) | 1.3148 ± 0.0693 mas[1] |
Distance | 2,500 ± 100 ly (760 ± 40 pc) |
Details | |
Mass | 16.9±2.2[4] M☉ |
Radius | 192.76+26.3 −29[5] R☉ |
Luminosity | 12,470[a][3] L☉ |
Temperature | 3645[6] K |
Age | 10.0±1.6[4] Myr |
Other designations | |
Database references | |
SIMBAD | data |
V762 Cassiopeiae is a K-type red supergiant[3] located about 2,500 light-years away in the Cassiopeia constellation.[2] Its apparent magnitude is 5.86, which makes it visible to the naked eye.[2] It is a relatively cool star with an average surface temperature of 3645 K.[6]
Characteristics
This is an evolved K-type red supergiant star with a spectral type of K0 I.[3] It has around 16.9 times the Sun's mass[4] and 193 times the Sun's radius.[5] It radiates 12,470 times the solar luminosity[3] from its outer atmosphere at an effective temperature of 3645 K.[6] V762 Cassiopeiae is located 2,480 light-years away, based in a parallax from Gaia DR3, and is moving towards Earth at a velocity of 21.37 km/s.[1][b] Its age is estimated to be 10 million years.[4]
Hipparcos satellite data showed that the star is variable, and because of that it was given the variable star designation V762 Cassiopeiae, in 1999.[8] The variability amplitude in visible light is only about 0.1 magnitudes. There does not appear to be a consensus about the cause of the brightness variations; the International Variable Star Index lists it as an irregular variable,[9] but the General Catalogue of Variable Stars classifies it as a BY Draconis star.[10]
Distance and titleholding
Some websites claim V762 Cassiopeiae is the "farthest star visible to the naked eye", at a distance of 16,308 light-years.[11][12] This is inconsistent with parallax measurements from both Hipparcos, which found a parallax of 1.18±0.45 mas, corresponding to a distance of about 2,800 light-years,[13] and Gaia DR3, which lists a parallax of 1.3148±0.0693 mas, corresponding to a distance of about 2,500 light-years.[1][b] The websites claiming that V762 Cassiopeiae is the "farthest star visible to the naked eye" also do not cite any references for the distance of 16,308 light-years, making the origin of this value uncertain.
References
- ^ a b c d e f g 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 c d "HD 7389". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 9 April 2024.
- ^ a b c d e f Messineo, M.; Brown, A. G. A. (2019-07-01). "A Catalog of Known Galactic K-M Stars of Class I Candidate Red Supergiants in Gaia DR2". The Astronomical Journal. 158 (1): 20. arXiv:1905.03744. Bibcode:2019AJ....158...20M. doi:10.3847/1538-3881/ab1cbd. ISSN 0004-6256. Data can be acessed here at VizieR.
- ^ a b c d Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (2011-01-01). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. ISSN 0035-8711.
{{cite journal}}
: CS1 maint: unflagged free DOI (link) Data can be acessed here at VizieR. - ^ a b Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012-11-01). "Fundamental parameters and infrared excesses of Hipparcos stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. ISSN 0035-8711.
{{cite journal}}
: CS1 maint: unflagged free DOI (link) - ^ EAS (1997). "The HIPPARCOS and TYCHO catalogues". Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission. ESA SP Series. 1200. Noordwijk, Netherlands: ESA Publications Division. Bibcode:1997HIP...C......0E. ISBN 9290923997. Retrieved 15 October 2022.
- ^ Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. (January 1999). "The 74th Special Name-list of Variable Stars" (PDF). Information Bulletin on Variable Stars. 4659: 1. Retrieved 8 May 2024.
- ^ "V0762 Cas". The International Variable Star Index. AAVSO. Retrieved 8 May 2024.
- ^ "Query= V762 Cas". General Catalogue of Variable Stars. Lomonosov Moscow State University. Retrieved 8 May 2024.
- ^ "Farthest Star You Can See With The Unaided Eye". Cosmoknowledge. 2021-03-26. Retrieved 2024-04-11.
- ^ "How Far Back In Time Can We See With Our Naked Eye?". Big Think. 2021-05-17. Retrieved 2024-04-11.
- ^ "HIP 5926". VizieR. Centre de données astronomiques de Strasbourg. Retrieved 11 April 2024.