Gamma Persei

γ Persei
	Location of γ Persei (circled)
Observation data; Epoch J2000.0 Equinox J2000.0
Constellation	Perseus
Right ascension	03h 04m 47.82011s
Declination	+53° 30′ 23.2626″
Apparent magnitude (V)	2.93
Characteristics
Spectral type	G8III + A2V
U−B color index	+0.45
B−V color index	+0.70
Variable type	EA
Astrometry
Radial velocity (Rv)	+2.5 km/s
Proper motion (μ)	RA: −14.194 mas/yr ; Dec.: −8.684 mas/yr
Parallax (π)	14.1252 ± 0.7684 mas
Distance	229+15; −13 ly ; (70.3+4.5; −4 pc)
Absolute magnitude (MV)	–1.50 (–1.23/0.01)
Orbit
Period (P)	14.6 yr
Semi-major axis (a)	0.144″
Eccentricity (e)	0.785
Inclination (i)	90.9°
Longitude of the node (Ω)	244.1°
Periastron epoch (T)	1991.08 Besselian
Argument of periastron (ω); (secondary)	170.0°
Details
γ Per A
Mass	2.7 M☉
Radius	29.4 R☉
Surface gravity (log g)	2.83 cgs
Temperature	5,170 K
Metallicity [Fe/H]	–0.19 dex
Rotation	5,350 days
Rotational velocity (v sin i)	50.0 km/s
γ Per B
Mass	1.65 M☉
Temperature	7,895 K
Other designations
	γ Persei, γ Per, Gamma Per, 23 Persei, BD+52 654, CCDM J03048+5331AP, FK5 108, GC 3664, HD 18925, HIP 14328, HR 915, IDS 02576+5307 AP, PPM 28201, SAO 23789, WDS J03048+5330Aa,Ab.
Database references
SIMBAD	data

Gamma Persei (Gamma Per, γ Persei, γ Per) is a binary star system in the constellation Perseus. The combined apparent visual magnitude of the pair is +2.9,^[2] making it the fourth-brightest member of the constellation. The distance to this system is of roughly 229 light-years (70 parsecs) with a 6% margin of error.^[6] About 4° to the north of Gamma Persei is the radiance point for the annual Perseid meteor shower.^[11]

This is a wide eclipsing binary system with an orbital period of 5,329.8 days (14.6 years).^[12] This eclipse was first observed in 1990 and lasted for two weeks.^[13] During an eclipse, the primary passes in front of the secondary, causing the magnitude of the system to decrease by 0.55.^[14] The primary component of this system is a giant star with a stellar classification of G9 III.^[15] It has a projected rotational velocity of 50.0 km s⁻¹ and a lengthy estimated rotation period of 14.6 years.^[7] The classification of the secondary remains tentative, with assignments of A3 V^[8] and A2(III).^[15] The primary has an angular diameter of 3.894±0.018 mas,^[16] translating to 29.4 at the estimated distance.^[9]

Mass estimates for the two stars remain disparate. Using speckle interferometry, McAlister (1982) obtained mass estimates of 4.73 M_☉ for the primary and 2.75 M_☉ for the secondary, where M_☉ is the mass of the Sun. He noted that the mass estimate was too high for the given classification of the primary.^[17] Martin and Mignard (1998) determined masses for both components based on data from the Hipparcos mission: 5.036 ± 0.951 M_☉ for the primary and 2.295 ± 0.453 M_☉ for the secondary. They admit that the high inclination of the orbit resulted in a large margin of error.^[18] Prieto and Lambert (1999) came up with a mass estimate of 3.81 M_☉ for the primary,^[19] while Pizzolato and Maggio (2000) obtained 4.34 M_☉.^[7] Ling et al. (2001) obtained estimates of 2.7 M_☉ for the primary and 1.65 M_☉ for the secondary,^[8] while Kaler (2001) obtained 2.5 and 1.9, respectively.^[13]

Name and etymology[edit]

This star, together with δ Per, ψ Per, σ Per, α Per and η Per, has been called the Segment of Perseus.^[20]
In Chinese, 天船 (Tiān Chuán), meaning Celestial Boat, refers to an asterism consisting of γ Persei, η Persei, α Persei, ψ Persei, δ Persei, 48 Persei, μ Persei and HD 27084. Consequently, the Chinese name for γ Persei itself is 天船二 (Tiān Chuán èr, English: the Second Star of Celestial Boat.)^[21]

References[edit]

^ ^a ^b ^c ^d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
^ ^a ^b ^c ^d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J
^ Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical masses of a selected sample of orbital binaries". Astronomy & Astrophysics. 546: A69. Bibcode:2012A&A...546A..69M. doi:10.1051/0004-6361/201219774.
^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
^ Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Washington, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W
^ ^a ^b Bailer-Jones, C. A. L.; Rybizki, J.; Fouesneau, M.; Demleitner, M.; Andrae, R. (2021). "Estimating Distances from Parallaxes. V. Geometric and Photogeometric Distances to 1.47 Billion Stars in Gaia Early Data Release 3". The Astronomical Journal. 161 (3): 147. arXiv:2012.05220. Bibcode:2021AJ....161..147B. doi:10.3847/1538-3881/abd806. S2CID 228063812. Data about this star can be seen here.
^ ^a ^b ^c ^d ^e Pizzolato, N.; Maggio, A.; Sciortino, S. (September 2000), "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases", Astronomy and Astrophysics, 361: 614–628, Bibcode:2000A&A...361..614P
^ ^a ^b ^c ^d ^e ^f ^g Ling, J. F.; Magdalena, P.; Prieto, C. (October 2001), "Perturbations by Mass Loss in the Orbital Elements of γ Persei and α Centauri", Revista Mexicana de Astronomía y Astrofísica, 37: 179–186, Bibcode:2001RMxAA..37..179L
^ ^a ^b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3 ed.), Birkhäuser, ISBN 978-3-540-29692-8. The radius (R_*) is given by:
${\begin{aligned}2\cdot R_{*}&={\frac {(70.269\cdot 3.894\cdot 10^{-3})\ {\text{UA}}}{0.0046491\ {\text{UA}}/R_{\bigodot }}}\\&\approx 58.86\cdot R_{\bigodot }\end{aligned}}$
^ ^a ^b ^c McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527
^ Burnham, Robert (1978), Burnham's celestial handbook: an observer's guide to the universe beyond the solar system, Dover books explaining science, vol. 3 (2nd ed.), Courier Dover Publications, p. 420, ISBN 0486236730
^ Pourbaix, D.; Boffin, H. M. J. (February 2003), "Reprocessing the Hipparcos Intermediate Astrometric Data of spectroscopic binaries. II. Systems with a giant component", Astronomy and Astrophysics, 398 (3): 1163–1177, arXiv:astro-ph/0211483, Bibcode:2003A&A...398.1163P, doi:10.1051/0004-6361:20021736, S2CID 12361870
^ ^a ^b Kaler, James B. (January 5, 2001), "GAMMA PER (Gamma Persei)", Stars, University of Illinois, retrieved 2012-02-25
^ Malkov, O. Yu.; et al. (February 2006), "A catalogue of eclipsing variables", Astronomy and Astrophysics, 446 (2): 785–789, Bibcode:2006A&A...446..785M, doi:10.1051/0004-6361:20053137, hdl:10995/73280
^ ^a ^b Ginestet, N.; Carquillat, J. M. (December 2002), "Spectral Classification of the Hot Components of a Large Sample of Stars with Composite Spectra, and Implication for the Absolute Magnitudes of the Cool Supergiant Components", The Astrophysical Journal Supplement Series, 143 (2): 513–537, Bibcode:2002ApJS..143..513G, doi:10.1086/342942
^ Baines, Ellyn K.; Clark, James H., III; Schmitt, Henrique R.; Stone, Jordan M.; von Braun, Kaspar (2023-12-01). "33 New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble". The Astronomical Journal. 166 (6): 268. Bibcode:2023AJ....166..268B. doi:10.3847/1538-3881/ad08be. ISSN 0004-6256.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ McAlister, H. A. (March 1982), "Masses and luminosities for the giant spectroscopic/speckle interferometric binaries gamma Persei and phi Cygni", Astronomical Journal, 87: 563–569, Bibcode:1982AJ.....87..563M, doi:10.1086/113130
^ Martin, C.; Mignard, F. (February 1998), "Mass determination of astrometric binaries with Hipparcos. II. Selection of candidates and results", Astronomy and Astrophysics, 330: 585–599, Bibcode:1998A&A...330..585M
^ Allende Prieto, C.; Lambert, D. L. (1999), "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: masses, radii and effective temperatures", Astronomy and Astrophysics, 352: 555–562, arXiv:0809.0359, Bibcode:1999A&A...352..555A, doi:10.1051/0004-6361/200811242, S2CID 14531031
^ 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.
^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日 Archived 2012-02-04 at the Wayback Machine

[dr3-1] Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.

[clpl4_99-2] Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J

[malkov-3] Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical masses of a selected sample of orbital binaries". Astronomy & Astrophysics. 546: A69. Bibcode:2012A&A...546A..69M. doi:10.1051/0004-6361/201219774.

[gcvs-4] Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.

[gcsrv-5] Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Washington, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W

[b-j-6] Bailer-Jones, C. A. L.; Rybizki, J.; Fouesneau, M.; Demleitner, M.; Andrae, R. (2021). "Estimating Distances from Parallaxes. V. Geometric and Photogeometric Distances to 1.47 Billion Stars in Gaia Early Data Release 3". The Astronomical Journal. 161 (3): 147. arXiv:2012.05220. Bibcode:2021AJ....161..147B. doi:10.3847/1538-3881/abd806. S2CID 228063812. Data about this star can be seen here.

[aaa361_614-7] Pizzolato, N.; Maggio, A.; Sciortino, S. (September 2000), "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases", Astronomy and Astrophysics, 361: 614–628, Bibcode:2000A&A...361..614P

[rmaa37_179-8] ^ ^a ^b ^c ^d ^e ^f ^g Ling, J. F.; Magdalena, P.; Prieto, C. (October 2001), "Perturbations by Mass Loss in the Orbital Elements of γ Persei and α Centauri", Revista Mexicana de Astronomía y Astrofísica, 37: 179–186, Bibcode:2001RMxAA..37..179L

[lang2006-9] Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3 ed.), Birkhäuser, ISBN 978-3-540-29692-8. The radius (R_*) is given by:
${\begin{aligned}2\cdot R_{*}&={\frac {(70.269\cdot 3.894\cdot 10^{-3})\ {\text{UA}}}{0.0046491\ {\text{UA}}/R_{\bigodot }}}\\&\approx 58.86\cdot R_{\bigodot }\end{aligned}}$

[ajss74_1075-10] McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527

[burnham1978-11] Burnham, Robert (1978), Burnham's celestial handbook: an observer's guide to the universe beyond the solar system, Dover books explaining science, vol. 3 (2nd ed.), Courier Dover Publications, p. 420, ISBN 0486236730

[aaa398_1163-12] Pourbaix, D.; Boffin, H. M. J. (February 2003), "Reprocessing the Hipparcos Intermediate Astrometric Data of spectroscopic binaries. II. Systems with a giant component", Astronomy and Astrophysics, 398 (3): 1163–1177, arXiv:astro-ph/0211483, Bibcode:2003A&A...398.1163P, doi:10.1051/0004-6361:20021736, S2CID 12361870

[kaler-13] Kaler, James B. (January 5, 2001), "GAMMA PER (Gamma Persei)", Stars, University of Illinois, retrieved 2012-02-25

[aaa446_2_785-14] Malkov, O. Yu.; et al. (February 2006), "A catalogue of eclipsing variables", Astronomy and Astrophysics, 446 (2): 785–789, Bibcode:2006A&A...446..785M, doi:10.1051/0004-6361:20053137, hdl:10995/73280

[apjss143_2_513-15] Ginestet, N.; Carquillat, J. M. (December 2002), "Spectral Classification of the Hot Components of a Large Sample of Stars with Composite Spectra, and Implication for the Absolute Magnitudes of the Cool Supergiant Components", The Astrophysical Journal Supplement Series, 143 (2): 513–537, Bibcode:2002ApJS..143..513G, doi:10.1086/342942

[npoi-16] Baines, Ellyn K.; Clark, James H., III; Schmitt, Henrique R.; Stone, Jordan M.; von Braun, Kaspar (2023-12-01). "33 New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble". The Astronomical Journal. 166 (6): 268. Bibcode:2023AJ....166..268B. doi:10.3847/1538-3881/ad08be. ISSN 0004-6256.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[aj87_563-17] McAlister, H. A. (March 1982), "Masses and luminosities for the giant spectroscopic/speckle interferometric binaries gamma Persei and phi Cygni", Astronomical Journal, 87: 563–569, Bibcode:1982AJ.....87..563M, doi:10.1086/113130

[aaa330_585-18] Martin, C.; Mignard, F. (February 1998), "Mass determination of astrometric binaries with Hipparcos. II. Selection of candidates and results", Astronomy and Astrophysics, 330: 585–599, Bibcode:1998A&A...330..585M

[aaa352_555-19] Allende Prieto, C.; Lambert, D. L. (1999), "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: masses, radii and effective temperatures", Astronomy and Astrophysics, 352: 555–562, arXiv:0809.0359, Bibcode:1999A&A...352..555A, doi:10.1051/0004-6361/200811242, S2CID 14531031

[allen1899-20] 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.

[21] (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日 Archived 2012-02-04 at the Wayback Machine

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

Observation data Epoch J2000.0 Equinox J2000.0
Location of γ Persei (circled)
Constellation	Perseus
Right ascension	03^h 04^m 47.82011^s^[1]
Declination	+53° 30′ 23.2626″^[1]
Apparent magnitude (V)	2.93^[2]
Characteristics
Spectral type	G8III + A2V^[3]
U−B color index	+0.45^[2]
B−V color index	+0.70^[2]
Variable type	EA^[4]
Astrometry

Radial velocity (R_v)	+2.5^[5] km/s
Proper motion (μ)	RA: −14.194 mas/yr^[1] Dec.: −8.684 mas/yr^[1]
Parallax (π)	14.1252 ± 0.7684 mas^[1]
Distance	229+15 −13 ly (70.3+4.5 −4 pc)^[6]
Absolute magnitude (M_V)	–1.50^[7] (–1.23/0.01)^[8]

Orbit^[8]
Period (P)	14.6 yr
Semi-major axis (a)	0.144″
Eccentricity (e)	0.785
Inclination (i)	90.9°
Longitude of the node (Ω)	244.1°
Periastron epoch (T)	1991.08 Besselian
Argument of periastron (ω) (secondary)	170.0°
Details
γ Per A
Mass	2.7^[8] `M`_☉
Radius	29.4^[9] `R`_☉
Surface gravity (log g)	2.83^[10] cgs
Temperature	5,170^[10] K
Metallicity [Fe/H]	–0.19^[10] dex
Rotation	5,350 days^[7]
Rotational velocity (v sin i)	50.0^[7] km/s
γ Per B
Mass	1.65^[8] `M`_☉
Temperature	7,895^[8] K
Other designations
γ Persei, γ Per, Gamma Per, 23 Persei, BD+52 654, CCDM J03048+5331AP, FK5 108, GC 3664, HD 18925, HIP 14328, HR 915, IDS 02576+5307 AP, PPM 28201, SAO 23789, WDS J03048+5330Aa,Ab.
Database references
SIMBAD	data