27 Cancri
View on Wikipedia| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Cancer[2] |
| Right ascension | 08h 26m 43.94035s[3] |
| Declination | +12° 39′ 16.6066″[3] |
| Apparent magnitude (V) | +5.41 to 5.75[4] |
| Characteristics | |
| Evolutionary stage | Asymptotic giant branch[5] |
| Spectral type | M3 IIIa[6] |
| B−V color index | 1.608±0.002[2] |
| Variable type | SRb[5] |
| Astrometry | |
| Radial velocity (Rv) | −8.30±0.31[7] km/s |
| Proper motion (μ) | RA: −19.760[3] mas/yr Dec.: −104.664[3] mas/yr |
| Parallax (π) | 3.3094±0.3176 mas[3] |
| Distance | 990 ± 90 ly (300 ± 30 pc) |
| Absolute magnitude (MV) | −1.62[2] |
| Details | |
| Radius | 119[3] R☉ |
| Luminosity | 2,455+707 −550[8] L☉ |
| Surface gravity (log g) | 1.00[8] cgs |
| Temperature | 3,574[8] K |
| Metallicity [Fe/H] | 0.00[8] dex |
| Other designations | |
| 27 Cnc, BP Cancri, AAVSO 0821+13, BD+13°1912, FK5 2658, GC 11525, HD 71250, HIP 41400, HR 3319, SAO 97819[9] | |
| Database references | |
| SIMBAD | data |
27 Cancri is a single[10] star in the zodiac constellation of Cancer, located around 990 light-years away from the Sun.[3] It is visible to the naked eye as a faint, red-hued star with a typical apparent visual magnitude of around +5.5. The star is moving closer to the Earth with a heliocentric radial velocity of −8.3 km/s.[7] It is a member of the Arcturus stream, a group of stars with high proper motion and metal-poor properties thought to be the remnants of a small galaxy consumed by the Milky Way.[11]
The variability of the brightness of 27 Cancri was announced by Joel Stebbins and Charles Morse Huffer in 1928, based on observations made at Washburn Observatory.[12] It was given its variable star designation, BP Cancri, in 1977.[13]
This is an aging red giant with a stellar classification of M3 IIIa,[6] currently on the asymptotic giant branch.[5] It is classified as a semiregular variable star of type SRb and its brightness varies from magnitude +5.41 to +5.75 with a period of 40 days.[4] The star is radiating around 2,455[8] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,574 K.[8]
References
[edit]- ^ 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:1997ESASP1200.....E. ISBN 9290923997. Retrieved 7 December 2024.
{{cite journal}}: CS1 maint: periodical has ISBN (link) - ^ a b c 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 g 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 Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
- ^ a b c Lebzelter, T.; Hron, J. (December 2003), "Technetium and the third dredge up in AGB stars. I. Field stars", Astronomy and Astrophysics, 411 (3): 533–542, arXiv:astro-ph/0310018, Bibcode:2003A&A...411..533L, doi:10.1051/0004-6361:20031458, S2CID 18879265.
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373, S2CID 123149047.
- ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ a b c d e f Maas, Z. G.; et al. (December 2016), "Chlorine Abundances in Cool Stars", The Astronomical Journal, 152 (6): 14, arXiv:1609.01626, Bibcode:2016AJ....152..196M, doi:10.3847/0004-6256/152/6/196, S2CID 118722950, 196.
- ^ "27 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-26.
- ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Eggen, Olin (1971), "The Arcturus Group", Publications of the Astronomical Society of the Pacific, 83 (493): 271–85, Bibcode:1971PASP...83..271E, doi:10.1086/129120.
- ^ Stebbins, Joel; Huffer, C. M. (1928). "The Constancy of the Light of Red Stars". Publications of the Washburn Observatory. 15: 137–174. Bibcode:1928PWasO..15..137S.
- ^ Kukarkin, B. V.; Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (October 1973). "59th Name-List of Variable Stars" (PDF). Information Bulletin on Variable Stars. 834: 1–22. Bibcode:1973IBVS..834....1K. Retrieved 8 December 2024.
