Sigma Persei


σ Persei
Perseus constellation map.svg
Red circle.svg
Location of σ Persei (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Perseus
Right ascension 03h 30m 34.48545s[1]
Declination 47° 59′ 42.7808″[1]
Apparent magnitude (V) 4.36[2]
Spectral type K3III[3]
U−B color index +1.54[2]
B−V color index +1.35[2]
Radial velocity (Rv)+14.36[4] km/s
Proper motion (μ) RA: +3.56[1] mas/yr
Dec.: +18.48[1] mas/yr
Parallax (π)9.07 ± 0.26[1] mas
Distance360 ± 10 ly
(110 ± 3 pc)
Absolute magnitude (MV)-0.85[5]
Mass1.32[6] M
Radius36.89[6] R
Luminosity368[6] L
Surface gravity (log g)1.46[6] cgs
Temperature4,165[6] K
Metallicity [Fe/H]-0.20[6] dex
Rotational velocity (v sin i)< 1.0[7] km/s
Other designations
σ Persei, σ Per, Sigma Per, 35 Persei, BD+47°843, FK5 124, GC 4158, HD 21552, HIP 16335, HR 1052, NSV 1167, PPM 46257, SAO 38890
Database references
σ Persei in optical light

Sigma Persei (Sigma Per, σ Persei, σ Per) is an orange K-type giant[3] with an apparent magnitude of +4.36.[2] It is approximately 360 light years from Earth.[1]

Sigma Persei is moving through the Galaxy at a speed of 17.4 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,400 and 43,600 light years from the center of the Galaxy. It came closest to the Sun 5.1 million years ago when it had brightened to magnitude 3.11 from a distance of 202 light years.[8]

It has one reported planet, b, with a period of 580 days and a mass approximately 6.5 times that of Jupiter.[9]

Name and etymology

This star, together with δ Per, ψ Per, α Per, γ Per and η Per, has been called the Segment of Perseus.[10]


  1. ^ a b c d e f 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. Vizier catalog entry
  2. ^ a b c d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ a b Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H. 5050. Bibcode:1995yCat.5050....0H.
  4. ^ Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data". Astronomy & Astrophysics. 430: 165–186. arXiv:astro-ph/0409579. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. S2CID 17804304.
  5. ^ 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. Vizier catalog entry
  6. ^ a b c d e f Reffert, Sabine; Bergmann, Christoph; Quirrenbach, Andreas; Trifonov, Trifon; Künstler, Andreas (2015). "Precise radial velocities of giant stars". Astronomy & Astrophysics. 574: A116. arXiv:1412.4634. Bibcode:2015A&A...574A.116R. doi:10.1051/0004-6361/201322360. hdl:10722/215277. S2CID 59334290. Vizier catalog entry
  7. ^ De Medeiros, J. R.; Mayor, M. (1999). "A catalog of rotational and radial velocities for evolved stars". Astronomy and Astrophysics Supplement Series. 139 (3): 433. arXiv:astro-ph/0608248. Bibcode:1999A&AS..139..433D. doi:10.1051/aas:1999401. Vizier catalog entry
  8. ^ Sigma Persei (HIP 16335)
  9. ^ Lee, Byeong-Cheol; Han, Inwoo; Park, Myeong-Gu; Mkrtichian, David E.; Jeong, Gwanghui; Kim, Kang-Min; Valyavin, Gennady (2014). "PLANETARY COMPANION IN K GIANT σ PERSEI". Journal of the Korean Astronomical Society. 47 (2): 69. arXiv:1405.2130. Bibcode:2014JKAS...47...69L. doi:10.5303/JKAS.2014.47.2.69.
  10. ^ Allen, R. H. (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York: Dover Publications Inc. p. 331. ISBN 0-486-21079-0. Retrieved 2012-09-04.