Upsilon2 Cancri (υ2 Cancri) is a faint, yellow-hued star in the zodiac constellation of Cancer. It is near the lower brightness limit of stars that can be viewed with the naked eye, having an apparent visual magnitude of +6.35.[2] Based upon an annual parallax shift of 5.1325 mas as seen from our orbit,[1] this system is roughly 635 light-years away.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 33m 00.10385s[1] |
| Declination | +24° 05′ 05.2560″[1] |
| Apparent magnitude (V) | +6.35[2] |
| Characteristics | |
| Spectral type | G9 III[3] |
| U−B color index | +0.88[2] |
| B−V color index | +1.02[2] |
| Astrometry | |
| Radial velocity (Rv) | +73.7±0.5[4] km/s |
| Proper motion (μ) | RA: −63.80[1] mas/yr Dec.: −46.40[1] mas/yr |
| Parallax (π) | 5.1325 ± 0.0407 mas[5] |
| Distance | 635 ± 5 ly (195 ± 2 pc) |
| Absolute magnitude (MV) | +1.13[3] |
| Details | |
| Radius | 15.43[5] R☉ |
| Luminosity | 120[5] L☉ |
| Surface gravity (log g) | 2.43±0.11[6] cgs |
| Temperature | 4881±44[6] K |
| Metallicity [Fe/H] | 0.00±0.05[6] dex |
| Rotational velocity (v sin i) | 2.7[7] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved G-type giant star with a stellar classification of G9 III.[3] It is radiating 98[9] times the Sun's luminosity from its photosphere at an effective temperature of 4,881 K.[6] Upsilon2 Cancri is a member of the Epsilon Indi Moving Group of stars that share a common motion through space.[3]
References
edit- ^ a b c d e van Leeuwen, F. (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 c d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
- ^ a b c d Eggen, O. J. (1958), "Stellar groups. II. The ζ Herculis, ε Indi and 61 Cygni groups of high-velocity stars", Monthly Notices of the Royal Astronomical Society, 118 (2): 154, Bibcode:1958MNRAS.118..154E, doi:10.1093/mnras/118.2.154.
- ^ 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 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 d Prugniel, Ph.; et al. (2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769, S2CID 54940439.
- ^ De Medeiros, J. R.; et al. (November 2000), "Rotation and lithium in single giant stars", Astronomy and Astrophysics, 363: 239–243, arXiv:astro-ph/0010273, Bibcode:2000A&A...363..239D.
- ^ "ups02 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-10.
- ^ McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.