Star in the constellation Perseus
1 Persei
Location of 1 Persei (circled)
Observation dataEpoch J2000.0 Equinox J2000.0
Constellation
Perseus
Right ascension
01h 51m 59.32008s [ 1]
Declination
+55° 08′ 50.5837″[ 1]
Apparent magnitude (V)
5.49 - 5.74 - 5.85[ 2]
Characteristics
Spectral type
B1.5V[ 2]
Variable type
eclipsing binary [ 3]
Astrometry Proper motion (μ) RA: 12.716(74)[ 1] mas /yr Dec.: −8.410(79)[ 1] mas /yr Parallax (π)2.6944± 0.0888 mas [ 1] Distance 1,210 ± 40 ly (370 ± 10 pc ) Absolute magnitude (MV )−1.37/−1.77[ 4]
Orbit [ 4] Primary 1 Persei A Companion 1 Persei B Period (P) 25.935951 ± 0.000003 dEccentricity (e) 0.3768± 0.0014Inclination (i) 88.048± 0.002 °Periastron epoch (T) 2443 563 .466± 0.005 HJD Argument of periastron (ω) (secondary) 109.83± 0.10 °Semi-amplitude (K1 ) (primary) 97.4± 0.1 km/sSemi-amplitude (K2 ) (secondary) 91.2± 0.1 km/s
Details[ 4] Primary Mass 6.95 M ☉ Radius 3.29 R ☉ Luminosity 2,188 L ☉ Surface gravity (log g )4.25 cgs Temperature 21,500 K Rotation 1.45 days Rotational velocity (v sin i )115 km/s Secondary Mass 7.42 M ☉ Radius 3.86 R ☉ Luminosity 3,311 L ☉ Surface gravity (log g )4.14 cgs Temperature 22,000 K Rotation 1.40 days Rotational velocity (v sin i )140 km/s
Other designations V436 Persei , BD +54 396 , HD 11241 , HIP 8704 , HR 533 , SAO 22690
Database references SIMBAD data
1 Persei (1 Per ) is an eclipsing binary [ 3] star in the constellation Perseus . Its uneclipsed apparent magnitude is 5.49. The binary star consists of two B2 type main-sequence stars in a 25.9 day eccentric orbit.[ 5] The stars are surrounded by a faint cloud of gas visible in mid-infrared, although whether they are the origin of the gas or simply passing through it is unclear.
Observational history
A visual band light curve for V436 Persei, adapted from Janik et al. (2003)[ 4]
The possible eclipsing binary nature of 1 Persei was first noticed by Donald Kurtz in 1977 when it was used as a comparison star to test for photometric variability of HD 11408 .[ 6] In 1979 French amateur observers succeeded in determining an orbital period of 25.9 days.[ 7] During the primary eclipse, the brightness drops to magnitude 5.85. In the secondary eclipses, the brightness drops to magnitude 5.74. The eclipses each last for approximately 25 hours.[ 2]
References
^ a b c d e Brown, A. G. A. ; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties" . Astronomy & Astrophysics . 649 : A1. arXiv :2012.01533 . Bibcode :2021A&A...649A...1G . doi :10.1051/0004-6361/202039657 . S2CID 227254300 . (Erratum: doi :10.1051/0004-6361/202039657e ) . Gaia EDR3 record for this source at VizieR .
^ a b c 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 .
^ a b North, P.; et al. (1981). "1 Per: a new eclipsing binary with a long period and an elliptical orbit" (PDF) . Information Bulletin on Variable Stars . 2036 : 1. Bibcode :1981IBVS.2036....1N .
^ a b c d Janík, J.; et al. (2003). "Search for forced oscillations in binaries. IV. The eclipsing binary V436 Per revisited" . Astronomy and Astrophysics . 408 (2): 611– 619. Bibcode :2003A&A...408..611J . doi :10.1051/0004-6361:20030960 .
^ Harmanec, P.; et al. (1997). "Search for forced oscillations in binaries. I. The eclipsing and spectroscopic binary V436 Persei = 1 Persei". Astronomy and Astrophysics . 319 (2): 867– 880. Bibcode :1997A&A...319..867H .
^ Kurtz, D. W. (1977). "The photometric variability of 1 Per" . Publications of the Astronomical Society of the Pacific . 89 : 939– 940. Bibcode :1977PASP...89..939K . doi :10.1086/130251 .
^ Figer, Alain; Maurin, Luc (1979). "1 Persei, a low amplitude eclipsing binary, has a period of 25.939 days and an elliptical orbit" . GEOS Circular on Eclipsing Binaries . 2 (EB 2). Bibcode :1979GEOCE...2.....F .