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70 Cancri 
Summary
70 Cancri is a star in the zodiac constellation of Cancer, located around 580 light years from the Sun.[1] It is a challenge to view with the naked eye even under good seeing conditions, having an apparent visual magnitude of 6.7.[2] The star is moving closer to the Earth with a heliocentric radial velocity of -21 km/s,[5] and is expected to come to within 44 light-years in around nine million years.[6] It is an A-type main-sequence star[3] with a stellar classification of A1V.[3] The object has a radius of about 2.7 R☉[7] and is radiating 76[6] times the Sun's luminosity from its photosphere at an effective temperature of 8,887 K.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 09h 04m 09.86704s[1] |
| Declination | +27° 53′ 53.9089″[1] |
| Apparent magnitude (V) | 6.665[2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | A1V[3] |
| U−B color index | +0.05[4] |
| B−V color index | +0.00[4] |
| Astrometry | |
| Radial velocity (Rv) | −21.0±4.4[5] km/s |
| Proper motion (μ) | RA: −1.287[1] mas/yr Dec.: −1.429[1] mas/yr |
| Parallax (π) | 5.6109 ± 0.1390 mas[1] |
| Distance | 580 ± 10 ly (178 ± 4 pc) |
| Absolute magnitude (MV) | 0.24[6] |
| Details | |
| Radius | 2.7[7] R☉ |
| Luminosity | 75.57[6] L☉ |
| Temperature | 8,887+352 −376[1] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
References edit
- ^ a b c d e f g h 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 Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
- ^ a b c Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal. 74: 375–406. Bibcode:1969AJ.....74..375C. doi:10.1086/110819.
- ^ a b Osawa, Kiyoteru (1959). "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of A0 V Stars". Astrophysical Journal. 130: 159. Bibcode:1959ApJ...130..159O. doi:10.1086/146706.
- ^ a b Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- ^ a b c d 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, S2CID 119257644.
- ^ a b Pasinetti Fracassini, L. E.; et al. (2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics". Astronomy & Astrophysics. 367 (2): 521–24. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
- ^ "70 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-09.