3 Cancri
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 00m 47.30744s[1] |
| Declination | +17° 18′ 31.3283″[1] |
| Apparent magnitude (V) | 5.60[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch(86%chance)[3] |
| Spectral type | K3 III[4] |
| B−V color index | 1.317[5] |
| Astrometry | |
| Radial velocity (Rv) | +39.55±0.16[1] km/s |
| Proper motion (μ) | RA: −10.403[1] mas/yr Dec.: −3.905[1] mas/yr |
| Parallax (π) | 4.0087 ± 0.1511 mas[1] |
| Distance | 810 ± 30 ly (249 ± 9 pc) |
| Absolute magnitude (MV) | −1.29[2] |
| Details | |
| Mass | 2.9[3] M☉ |
| Radius | 40[3] R☉ |
| Luminosity | 568.61[2] L☉ |
| Surface gravity (log g) | 2.05[5] cgs |
| Temperature | 4,300[5] K |
| Rotational velocity (v sin i) | 5.73[5] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
3 Cancri is a single[7] star in the zodiac constellation of Cancer, located around 810 light years from the Sun. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.60.[2] This object is moving further from the Earth with a heliocentric radial velocity of +39.5 km/s,[1] and may be a member of the Hyades group.[8] It is located near the ecliptic and thus is subject to lunar eclipses.[9]
This is an aging giant star with a stellar classification of K3 III[4] that is most likely (86% chance) on the horizontal branch.[3] The star has 2.9 times the mass of the Sun and has expanded to 40 times the Sun's radius.[3] It is radiating 569[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,300 K.[5]
Planetary system
[edit]One super-Jupiter exoplanet orbiting 3 Cancri was detected in 2020 on a very mildly eccentric orbit using the radial velocity method.[10]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period ([[]]s) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 20.76 MJ | 2.52 | 853.64 | 0.4 | — | — |
See also
[edit]References
[edit]- ^ 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 c d e 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 c d e Stock, S.; et al. (August 2018), "Precise radial velocities of giant stars. X. Bayesian stellar parameters and evolutionary stages for 372 giant stars from the Lick planet search", Astronomy & Astrophysics, 616: 15, arXiv:0709.1145, Bibcode:2018A&A...616A..33S, doi:10.1051/0004-6361/201833111, S2CID 119361866, A33.
- ^ a b Adams, Walter S.; et al. (1935), "The Spectroscopic Absolute Magnitudes and Parallaxes of 4179 Stars", Astrophysical Journal, 81: 187, Bibcode:1935ApJ....81..187A, doi:10.1086/143628
- ^ a b c d e Hekker, S.; Meléndez, J. (2007), "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters", Astronomy and Astrophysics, 475 (3): 1003–1009, arXiv:0709.1145, Bibcode:2007A&A...475.1003H, doi:10.1051/0004-6361:20078233, S2CID 10436552.
- ^ "3 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-22.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 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, O. J. (June 1972), "The red giants in the Hyades group", Publications of the Astronomical Society of the Pacific, 84: 406, Bibcode:1972PASP...84..406E, doi:10.1086/129303.
- ^ White, Nathaniel M.; Feierman, Barry H. (September 1987), "A Catalog of Stellar Angular Diameters Measured by Lunar Occultation", Astronomical Journal, 94: 751, Bibcode:1987AJ.....94..751W, doi:10.1086/114513.
- ^ Pinto, Marcelo Tala; Reffert, Sabine; Quirrenbach, Andreas; Stock, Stephan; Trifonov, Trifon; Mitchell, David S. (2020). "Precise radial velocities of giant stars". Astronomy & Astrophysics. 644: A1. doi:10.1051/0004-6361/202038285. hdl:10150/622444.
- ^ "The Extrasolar Planet Encyclopaedia — 3 Cnc b". Extrasolar Planets Encyclopaedia. Retrieved 2021-04-29.
