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HD 20104 (HR 967) is a visual binary in the northern circumpolar constellation Camelopardalis. The system has a combined apparent magnitude of 6.41, making it near naked eye visibility. When resolved in a large telescope, HD 20104 appears to be a pair of 7th magnitude A-type main-sequence stars with a separation of about 0.5″. Located approximately 550 light years away, the system is approaching the Sun with a heliocentric radial velocity of −6 km/s.

The system's stars have masses twice that of the Sun and effective temperatures ranging from 8,100 to 8,700 K, typical of stars their type. The primary radiates at 71.3 L_☉ − over luminous for its class − and spins with a projected rotational velocity of 159 km/s. HD 20104 has an age of 313 million years.

References

1. ^ Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (March 2002). "The Tycho double star catalogue". Astronomy & Astrophysics. 384 (1): 180–189. Bibcode:2002A&A...384..180F. doi:10.1051/0004-6361:20011822. ISSN 0004-6361.
2. ^ Edwards, T. W. (April 1976). "MK classification for visual binary components". The Astronomical Journal. 81: 245. Bibcode:1976AJ.....81..245E. doi:10.1086/111879. ISSN 0004-6256.
3. ^ Haupt, H. F.; Schroll, A. (1974). "Photoelektrische Photometrie von Shell-Sternen". Astronomy and Astrophysics Supplement Series. 15: 311–319. Bibcode:1974A&AS...15..311H. ISSN 0365-0138.
4. ^ Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Carnegie Institute Washington D.C. Publication: 0. Bibcode:1953GCRV..C......0W.
5. ^ van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. ISSN 0004-6361.
6. Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 119257644.
7. Heintz, W. D. (July 1998). "Observations of Double Stars. XVIII". The Astrophysical Journal Supplement Series. 117 (2): 587–598. Bibcode:1998ApJS..117..587H. doi:10.1086/313127.
8. ^ Cvetkovic, Zorica; Ninkovic, S. (2010). "On the component masses of visual binaries". Serbian Astronomical Journal. 180 (180): 71–80. Bibcode:2010SerAJ.180...71C. doi:10.2298/SAJ1080071C.
9. ^ Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; de Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. ISSN 0004-6361.
10. Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256.
11. ^ Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy and Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. ISSN 0004-6361. S2CID 55586789.
12. Royer, F.; Zorec, J.; Gómez, A. E. (February 2007). "Rotational velocities of A-type stars: III. Velocity distributions". Astronomy & Astrophysics. 463 (2): 671–682. arXiv:astro-ph/0610785. Bibcode:2007A&A...463..671R. doi:10.1051/0004-6361:20065224. ISSN 0004-6361.

v t e Constellation of Camelopardalis
Camelopardalis in Chinese astronomy List of stars in Camelopardalis
Stars	Bayer α β γ Flamsteed 1 2 3 4 5 7 8 11 12 14 15 16 17 18 19 20 21 22 23 24 26 28 29 30 31 33 34 35 36 37 38 39 40 41 42 43 49 51 53 Variable U Z RU ST TX VZ BD BE BK BN CE CO CQ CS DD MY HR 967 1046 1073 1112 1124 1129 1138 1158 1192 1204 1205 1241 1242 1305 1313 1314 1327 1335 1342 1401 1440 1491 1527 1561 1624 1636 (Mago) 1675 1683 1686 1720 1844 1916 2209 2363 2396 2401 2527 2581 2830 3075 3082 3216 4062 4084 4609 (Tonatiuh) 4892 4893 5009 5091 5203 HD 35759 Other 2MASS J05325346+8246465 Gliese 445 NGC 2363-V1 PSR B0329+54 Stein 2051 Struve 1694 XO-3 XO-6
Exoplanets HD 32518 b HD 33564 b HD 104985 b XO-3b XO-6b
Star clusters NGC 1502
Nebulae IC 3568 (Lemon Slice Nebula) M4-18 NGC 1501 NGC 2404
Galaxies	NGC 1530 1560 1569 1573 1573A 1961 2146 2336 2363 2366 2403 2441 2460 2523 2655 2715 2748 5640 Other DDO 44 IC 342 IRAS 07598+6508 MACS0647-JD UGC 3478 UGC 3730 UGCA 86
Galaxy clusters MACS J0647.7+7015 MS 0735.6+7421
Astronomical events SN 1996ah GRB 970508 SN 2004dj SN 2010lt
Category

• Camelopardalis
• A-type main-sequence stars
• Binary stars
• Henry Draper Catalogue objects
• Bright Star Catalogue objects
• Durchmusterung objects
• Hipparcos objects