2 Camelopardalis

2 Camelopardalis is a triple star[7] 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]

2 Camelopardalis

Observation data Epoch J2000      Equinox J2000
Constellation	Camelopardalis
Right ascension	04^h 39^m 58.06187^s[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[1] mas
Distance	213 ± 5 ly (65 ± 2 pc)
Orbit[5]
Primary	A
Companion	B
Period (P)	26.65 yr
Semi-major axis (a)	0.174
Eccentricity (e)	0.86
Inclination (i)	141.0°
Longitude of the node (Ω)	20.8°
Periastron epoch (T)	B 1988.90
Argument of periastron (ω) (secondary)	51.5°
Orbit[5]
Primary	AB
Companion	C
Period (P)	480.75 ± 3.81 yr
Semi-major axis (a)	1.514 ± 0.038
Eccentricity (e)	0.229 ± 0.012
Inclination (i)	128.4 ± 0.7°
Longitude of the node (Ω)	110.8 ± 0.8°
Periastron epoch (T)	B 2027.79 ± 3.26
Argument of periastron (ω) (secondary)	307.1 ± 5.0°
Details[6]
A
Mass	2.4 M☉
B
Mass	1.4 M☉
C
Mass	3.2 M☉
Other designations
2 Cam, BD+53° 794, HD 29316, HIP 21730, HR 1466, SAO 24744, ADS 3358 ABC, CCDM J04400+5328ABC, WDS 04400+5328
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.[5] The two orbit each other on a very eccentric orbit with a period of 26.65 years.[5] Further out, there is an eight-magnitude companion (designated component C), orbiting once every few hundred years.[5] Because the third star is relatively massive for its luminosity, it is possible that it may be a binary star itself.[6]

References

1. 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.
2. Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
3. 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.
4. 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.
5. "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Retrieved 4 April 2017.
6. Heintz, W. D. (1996). "A Study of Multiple-Star Systems". The Astronomical Journal. 111: 408. Bibcode:1996AJ....111..408H. doi:10.1086/117792.
7. 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.