2 Camelopardalis is a triple star[6] system in the northern circumpolar constellation of Camelopardalis, next to the southern constellation border with Perseus. It is dimly visible to the naked eye with a combined apparent visual magnitude of 5.36.[2] The system is located at a distance of about 213 light-years (65 parsecs) from the Sun, based on its parallax.[1] It is drifting further away with a radial velocity of +20 km/s.[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 04h 39m 58.06187s[1] |
| Declination | +53° 28′ 22.4654″[1] |
| Apparent magnitude (V) | 5.36[2] |
| Characteristics | |
| A | |
| Spectral type | A8V[3] |
| U−B color index | +0.05[2] |
| B−V color index | +0.34[2] |
| Astrometry | |
| Radial velocity (Rv) | +20.1±3.2[4] km/s |
| Proper motion (μ) | RA: +44.269[1] mas/yr Dec.: −77.004[1] mas/yr |
| Parallax (π) | 15.3220 ± 0.3790 mas[1] |
| Distance | 213 ± 5 ly (65 ± 2 pc) |
| Orbit[5] | |
| Primary | 2 Cam A |
| Companion | 2 Cam B |
| Period (P) | 26.34 ± 0.05 yr |
| Semi-major axis (a) | 0.1727 ± 0.0023″ |
| Eccentricity (e) | 0.846 ± 0.005 |
| Inclination (i) | 113.3 ± 3.4° |
| Longitude of the node (Ω) | 12.6 ± 2.5° |
| Periastron epoch (T) | B 1988.98 ± 0.03 |
| Argument of periastron (ω) (secondary) | 42.9 ± 2.6° |
| Orbit[5] | |
| Primary | 2 Cam AB |
| Companion | 2 Cam C |
| Period (P) | 660 yr |
| Semi-major axis (a) | 1.666 ± 0.019″ |
| Eccentricity (e) | 0.405 ± 0.015 |
| Inclination (i) | 132.5 ± 1.9° |
| Longitude of the node (Ω) | 286.2 ± 1.8° |
| Periastron epoch (T) | B 2011.7 ± 2.7 |
| Argument of periastron (ω) (secondary) | 105.1 ± 5.4° |
| Details[5] | |
| A | |
| Mass | 1.94 M☉ |
| B | |
| Mass | 1.45 M☉ |
| C | |
| Mass | 1.5 M☉ |
| Other designations | |
| Database references | |
| SIMBAD | 2 Cam |
| 2 Cam AB | |
| 2 Cam C | |
The primary member of 2 Camelopardalis, designated component A, is an A-type main-sequence star with a spectral type of A8V. It has an apparent magnitude of 5.86, and has a secondary with an apparent magnitude of 7.35, designated component B.[7] The two orbit each other on a very eccentric orbit with a period of 26.34 years.[5] Further out, there is an eight-magnitude companion (designated component C), orbiting once every few hundred years.[5] As the third star was previously thought to be relatively massive for its luminosity, it was suspected of being a binary star itself,[8] but the current estimate of component C's magnitude as a single star matches its absolute magnitude.[5]
References
edit- ^ a b c d e f 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 Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- ^ Appenzeller, Immo (1967). "MK Spectral Types for 185 Bright Stars". Publications of the Astronomical Society of the Pacific. 79 (467): 102. Bibcode:1967PASP...79..102A. doi:10.1086/128449.
- ^ a b Holmberg, J.; Nordström, B.; Andersen, J. (2007). "The Geneva-Copenhagen survey of the Solar neighbourhood II". Astronomy and Astrophysics. 475 (2): 519. arXiv:0707.1891. Bibcode:2007A&A...475..519H. doi:10.1051/0004-6361:20077221. S2CID 119054949.
- ^ a b c d e f Tokovinin, A. (2021). "Inner and Outer Orbits in 13 Resolved Hierarchical Stellar Systems". The Astronomical Journal. 161 (3): 144. arXiv:2101.02976. Bibcode:2021AJ....161..144T. doi:10.3847/1538-3881/abda42. S2CID 231419112.
- ^ 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.
- ^ "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 30 April 2017. Retrieved 4 April 2017.
- ^ Heintz, W. D. (1996). "A Study of Multiple-Star Systems". The Astronomical Journal. 111: 408. Bibcode:1996AJ....111..408H. doi:10.1086/117792.