Astronomy:Sigma Persei
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Perseus |
| Right ascension | 03h 30m 34.48537s[1] |
| Declination | +47° 59′ 42.7789″[1] |
| Apparent magnitude (V) | 4.36[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[3] |
| Spectral type | K3III[4] |
| U−B color index | +1.54[2] |
| B−V color index | +1.35[2] |
| Astrometry | |
| Radial velocity (Rv) | +14.32±0.15[1] km/s |
| Proper motion (μ) | RA: +3.954[1] mas/yr Dec.: +18.968[1] mas/yr |
| Parallax (π) | 9.5060 ± 0.2003[1] mas |
| Distance | 343 ± 7 ly (105 ± 2 pc) |
| Absolute magnitude (MV) | −0.85[5] |
| Details | |
| Mass | 1.32[3] M☉ |
| Radius | 36.89[3] R☉ |
| Luminosity | 368[3] L☉ |
| Surface gravity (log g) | 1.46[3] cgs |
| Temperature | 4,165[3] K |
| Metallicity [Fe/H] | −0.20[3] dex |
| Rotational velocity (v sin i) | 2.2[6] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Sigma Persei (Sigma Per, σ Persei, σ Per) is an orange K-type giant star[4] with an apparent magnitude of +4.36.[2] It is approximately 343 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]
In 2014 a planet was reported, Sigma Persei b, with a period of 580 days and a mass approximately 6.5 times that of Jupiter.[9] However, a 2025 study found that the observed radial velocity variations are intrinsic to the star, and not caused by a planetary companion.[10]
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.[11]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 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.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Reffert, Sabine; Bergmann, Christoph; Quirrenbach, Andreas; Trifonov, Trifon; Künstler, Andreas (2015). "Precise radial velocities of giant stars". Astronomy & Astrophysics 574: A116. doi:10.1051/0004-6361/201322360. Bibcode: 2015A&A...574A.116R. Vizier catalog entry
- ↑ 4.0 4.1 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.
- ↑ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A. Vizier catalog entry
- ↑ Hekker, S.; Meléndez, J. (2007). "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters". Astronomy and Astrophysics 475 (3): 1003. doi:10.1051/0004-6361:20078233. Bibcode: 2007A&A...475.1003H.
- ↑ "* sig Per". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+sig+Per.
- ↑ Sigma Persei (HIP 16335)
- ↑ 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. doi:10.5303/JKAS.2014.47.2.69. Bibcode: 2014JKAS...47...69L.
- ↑ Spaeth, Dane; Reffert, Sabine; Trifonov, Trifon; Kaminski, Adrian; Albrecht, Simon; Grundahl, Frank; Fredslund Andersen, Mads; Quirrenbach, Andreas et al. (2025). "Precise radial velocities of giant stars. XVII. Distinguishing planets from intrinsically induced radial velocity signals in evolved stars". Astronomy & Astrophysics. doi:10.1051/0004-6361/202453500.
- ↑ Allen, R. H. (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York: Dover Publications Inc.. p. 331. ISBN 0-486-21079-0. https://archive.org/details/starnamestheirlo00alle/page/331. Retrieved 2012-09-04.
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