Misplaced Pages

HR 7955 is a binary star system in the northern circumpolar constellation of Cepheus, near the constellation border with Cygnus. It has a yellow-white hue and is faintly visible to the naked eye with a combined apparent visual magnitude of 4.51. The system is located at a distance of 89 light-years (27.3 parsecs) from the Sun, based on parallax. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.243 arc seconds per annum, and is drifting closer to the Sun with a radial velocity of -33 km/s.

The double-lined nature of this spectroscopic binary system was not announced until 1972. It has an orbital period of 1.35 years and an eccentricity of 0.551. Both components appear to be slightly evolved stars that are leaving the main sequence and becoming subgiant stars, with stellar classifications of F8IV-V and F9IV-V. They each have slightly greater mass than the Sun: 107% and 105%, respectively. The system is about 2.25 billion years old.

References

1. ^ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
2. ^ Farrington, C. D.; et al. (2010). "Separated Fringe Packet Observations with the CHARA Array. I. Methods and New Orbits for χ Draconis, HD 184467, and HD 198084". The Astronomical Journal. 139 (6): 2308. Bibcode:2010AJ....139.2308F. doi:10.1088/0004-6256/139/6/2308. S2CID 122357261.
3. ^ Pourbaix, D.; et al. (2004). "S_B: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics. 424 (2): 727–732. arXiv:astro-ph/0406573. Bibcode:2004A&A...424..727P. doi:10.1051/0004-6361:20041213. S2CID 119387088.
4. Griffin, R. F.; Suchkov, A. A. (July 2003). "The Nature of Overluminous F Stars Observed in a Radial-Velocity Survey". The Astrophysical Journal Supplement Series. 147 (1): 103–144. Bibcode:2003ApJS..147..103G. doi:10.1086/367855.
5. ^ Griffin, R. F. (October 1999), "Spectroscopic binary orbits from photoelectric radial velocities. Paper 148: HR 7955", The Observatory, 119: 272–283, Bibcode:1999Obs...119..272G
6. ^ Luck, R. Earle (January 2017), "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants", The Astronomical Journal, 153 (1): 19, arXiv:1611.02897, Bibcode:2017AJ....153...21L, doi:10.3847/1538-3881/153/1/21, S2CID 119511744, 21.
7. "HD 198084". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 6 September 2012.
8. Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal. 129 (3): 1483–1522. arXiv:astro-ph/0412070. Bibcode:2005AJ....129.1483L. doi:10.1086/427854. S2CID 2603568.

v t e Constellation of Cepheus
List of stars in Cepheus Cepheus in Chinese astronomy
Stars	Bayer α (Alderamin) β (Alfirk) γ (Errai) δ ε ζ η θ ι κ λ μ (Garnet Star) ν ξ (Kurhah) ο π ρ ρ Flamsteed 7 9 11 14 16 19 24 2 UMi Variable AR T V W RW VV VW WZ DH DO MY PV S SS ST U V354 V381 V419 HR 597 881 7955 8281 8442 8702 8748 8938 9038 HD 1 197911 204521 Other Gliese 809 WISE 0313+7807 WR 156 IRAS 23077+6707
Exoplanets γ Cephei Ab (Tadmor) TOI-1431 b
Star clusters	NGC 188 6939 7023 7129 7142 7160 7380 7419 7429 7510 Other Palomar 1
Nebulae	NGC NGC 40 NGC 7129 NGC 7139 NGC 7354 NGC 7538 NGC 7822 Other Seahorse Nebula Elephant's Trunk Nebula Ghost Nebula Gyulbudaghian's Nebula IC 1396 Iris Nebula L1157 S 155 SSTGFLS J222557+601148
Galaxies	NGC 2276 2300 6952 Other 3C 61.1 S5 0014+81 NVSS 2146+82 UGC 11861
Category

• F-type main-sequence stars
• F-type subgiants
• Spectroscopic binaries
• Cepheus (constellation)
• Durchmusterung objects
• Gliese and GJ objects
• Henry Draper Catalogue objects
• Hipparcos objects
• Bright Star Catalogue objects