Pi Andromedae

Binary star system in the constellation Andromeda

Pi Andromedae
Observation data Epoch J2000 Equinox J2000
Location of π Andromedae (circled)
Constellation	Andromeda
Right ascension	00^h 36^m 52.85132^s^[1]
Declination	+33° 43′ 09.6363″^[1]
Apparent magnitude (V)	4.36^[2] (4.9/5.3)^[3]
Characteristics
Spectral type	B5 V^[4] (B5 V + B5 V^[3])
U−B color index	–0.55^[2]
B−V color index	–0.16^[2]
Astrometry

Radial velocity (R_v)	+8.7^[5] km/s
Proper motion (μ)	RA: 14.669(118)^[1] mas/yr Dec.: −3.385(93)^[1] mas/yr
Parallax (π)	5.6563 ± 0.1474 mas^[1]
Distance	580 ± 20 ly (177 ± 5 pc)

Orbit^[3]
Period (P)	143.6 days
Eccentricity (e)	0.56
Details

Luminosity	1,136^[6] `L`_☉
Surface gravity (log g)	4.10^[4] cgs
Temperature	15,276^[4] K
Metallicity [Fe/H]	–0.20^[4] dex
Rotational velocity (v sin i)	25^[7] km/s

Other designations
π Andromedae, 29 Andromedae, ADS 513, BD+32°101, FK5 18, HD 3369, HIP 2912, HR 154, SAO 54033, PPM 65480
Database references
SIMBAD	data

Pi Andromedae (Pi And, π Andromedae, π And) is the Bayer designation for a binary star^[3] system in the northern constellation of Andromeda. With an apparent visual magnitude of 4.4,^[2] it is visible to the naked eye. It is located approximately 580 light-years (180 parsecs) from Earth.^[1]

The pair is classified as a blue-white B-type main sequence dwarf, with an apparent magnitude of +4.34. It is a spectroscopic binary with an orbital period of 143.6 days and an eccentricity of 0.56. ^[3]

The spectroscopic binary forms a triple system with BD+32 102, a magnitude 8.6 star located 35.9 arcseconds away.^[3] At 55 arcseconds separation is an 11th magnitude companion that is just located on the same line of sight, but at a very different distance from us.

Naming

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism consisting of π Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, the Chinese name for π Andromedae itself is 奎宿六 (Kuí Sù liù, English: the Sixth Star of Legs.)^[8]

References

^ ^a ^b ^c ^d ^e ^f 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 ^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.
^ ^a ^b ^c ^d ^e ^f Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.
^ ^a ^b ^c ^d Cenarro, A. J.; et al. (January 2007), "Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters", Monthly Notices of the Royal Astronomical Society, 374 (2): 664–690, arXiv:astro-ph/0611618, Bibcode:2007MNRAS.374..664C, doi:10.1111/j.1365-2966.2006.11196.x, S2CID 119428437.
^ Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
^ 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.
^ Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590.
^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日

External links

Image Pi Andromedae

Constellation of Andromeda

Stars

Bayer	α (Alpheratz) β (Mirach) γ (Almach) δ ε ζ η θ ι κ λ μ ν ξ (Adhil) ο π ρ σ τ υ (Titawin) φ χ ψ ω A b c υ Per (Nembus)
Flamsteed	2 3 4 5 6 7 8 9 10 11 12 13 14 (Veritate) 15 18 22 23 26 28 32 36 39 41 44 45 47 55 56 58 59 63 64 65 66 6 Per
Variable	R T U W Z RT RV RX SU SW TU TW WZ XZ AB AC AD AE AF AR BM BX CC CG CN DS DX EG ET EU FF GP GQ GX GR GY HH HN IW KK KX KZ LL LN LP LQ OP OS OU PX PY QO QR QV QX V385 V428 V439 V455 V529 V807
HR	1 40 56 78 104 122 134 178 275 282 283 289 379 410 483 687 746 748 8884 8925 8950 8962 8973 9011 9074 9075 9105
HD	16175 (Buna) 222155
Other	3XMM J004232.1+411314 ADS 48 HAT-P-6 (Sterrennacht) HAT-P-16 HAT-P-19 HAT-P-28 M31-RV KELT-1 NGC 44 NGC 82 NGC 84 NGC 91 NGC 162 NGC 464 Qatar-3 Qatar-4 PA-99-N2 WASP-1 WISE 0146+4234 WISE J0005+3737 WISE J004945.61+215120.0

Exoplanets	14 Andromedae b κ Andromedae b υ Andromedae b c d Gliese 15 Ab c HD 13931 b HD 16175 b HAT-P-6b HAT-P-32b WASP-1b WASP-33b Qatar-4b Qatar-5b

Star
clusters

NGC	206 272 752 956 7686
Other	Mayall II RBC EXT8

Nebulae

NGC	7662

Galaxies

Messier	32 110
NGC	5 11 13 19 20 21 27 39 43 48 49 51 67 68 69 70 71 72 74 76 79 80 81 83 85 86 90 93 94 96 97 108 109 112 140 149 160 169 181 183 184 214 218 226 228 229 233 243 252 258 260 262 280 304 317 389 393 404 425 431 477 512 513 523 528 529 531 536 542 561 605 620 668 679 687 700 703 704 705 708 709 710 712 714 717 721 732 753 759 801 812 834 891 906 910 911 912 913 920 937 980 995 996 999 1000 7640 7836
Numbered	I II III IV V VIII IX X XI XVIII XIX XXI
Other	3C 66A 3C 66B Andromeda Galaxy Arp 273 Donatiello I