101 Piscium

101 Piscium is a star in the zodiac constellation of Pisces,^[9] located around 1,400 light years away from the Sun. This appears as a dim, blue-white hued star near the lower limit of visibility to the naked eye at an apparent visual magnitude of 6.23.^[2] It is a suspected variable star with the designation NSV 559;^[10] 101 Piscium is the Flamsteed designation. The star is moving closer to the Earth with a heliocentric radial velocity of −10 km/s.^[5]

101 Piscium

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Pisces
Right ascension	01h 35m 46.44226s[1]
Declination	+14° 39′ 41.1144″[1]
Apparent magnitude (V)	6.23[2]
Characteristics
Spectral type	B9.5 III[3]
U−B color index	−0.151[4]
B−V color index	−0.036±0.005[2]
Astrometry
Radial velocity (Rv)	−10.10[5] km/s
Proper motion (μ)	RA: +3.287[1] mas/yr Dec.: −8.052[1] mas/yr
Parallax (π)	2.3343 ± 0.0663 mas[1]
Distance	1,400 ± 40 ly (430 ± 10 pc)
Absolute magnitude (MV)	−2.07[2]
Details
Mass	4.53±0.51[6] M☉
Radius	3.6[7] R☉
Luminosity	1,037+523 −347[6] L☉
Surface gravity (log g)	2.907±0.028[8] cgs
Temperature	10,471+49 −48[6] K
Rotational velocity (v sin i)	246[6] km/s
Other designations
101 Psc, NSV 559, BD+13° 240, GC 1929, HD 9766, HIP 7436, HR 455, SAO 92530[9]
Database references
SIMBAD	data

This object has a stellar classification of B9.5 III,^[3] matching a giant star that has consumed the hydrogen at its core and is evolving away from the main sequence.^[6] It is spinning rapidly with a projected rotational velocity of 246^[6] km/s, compared to a critical velocity of 270 km/s.^[8] The star has 4.5^[6] times the mass of the Sun and about 3.6^[7] times the Sun's radius. It is radiating around 1,000^[6] times the luminosity of the Sun from its photosphere at an effective temperature of 10,471 K.^[6]

References

1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. 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.
3. Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal. 74: 375–406. Bibcode:1969AJ.....74..375C. doi:10.1086/110819.
4. Gutierrez-Moreno, Adelina; et al. (1966). "A System of photometric standards". Publications of the Department of Astronomy University of Chile. 1. Publicaciones Universidad de Chile, Department de Astronomy: 1–17. Bibcode:1966PDAUC...1....1G.
5. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
6. Zorec, J.; et al. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy and Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. S2CID 55586789.
7. Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)". Astronomy and Astrophysics. 367 (Third ed.): 521–524. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
8. Huang, W.; et al. (2010). "A Stellar Rotation Census of B Stars: From ZAMS to TAMS". The Astrophysical Journal. 722 (1): 605–619. arXiv:1008.1761. Bibcode:2010ApJ...722..605H. doi:10.1088/0004-637X/722/1/605. S2CID 118532653.
9. "35 Psc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-24.
10. Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.

External links

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