Binary star system in the constellation Andromeda
2 Andromedae Location of 2 Andromedae (circled)
Observation dataEpoch J2000 Equinox J2000 Constellation Andromeda Right ascension 23h 02m 36.38176s [ 1] Declination +42° 45′ 28.0628″[ 1] Apparent magnitude (V)5.09[ 2] [ 3] Characteristics 2 And A Spectral type A1V[ 4] U−Bcolor index +0.10[ 5] B−Vcolor index +0.08[ 5] 2 And B Spectral type F1V/F4V[ 3] Variable type δ Sct ?[ 3] Astrometry 2 And A Radial velocity (Rv )± 2.4[ 6] km/s Proper motion (μ)RA: 56.38[ 1] mas /yr Dec.: −4.47[ 1] mas /yr Parallax (π)7.74± 0.51 mas [ 1] Distance 420 ± 30 ly pc ) Absolute magnitude (MV )± 0.16[ 7] 2 And B Absolute magnitude (MV )± 0.16[ 7] Orbit [ 3] Period (P)± 0.509yr Semi-major axis (a)± 0.011Eccentricity (e)± 0.056Inclination (i)± 46.0Longitude of the node (Ω)± 2.0Periastron epoch (T)870 .280± 0.595Argument of periastron (ω)± 3.0Details 2 And A Mass ± 0.1[ 7] M ☉ Luminosity 130.50[ 2] L ☉ Surface gravity (log g )± 0.12[ 7] cgs Temperature ± 250[ 7] K Rotational velocity (v sin i )212[ 8] Age +309 [ 9] Myr 2 And B Mass ± 0.06[ 7] M ☉ Surface gravity (log g )± 0.16[ 7] cgs Temperature ± 250[ 7] K Other designations 2 And ,BD +41°4665GJ 886.1HD 217782HIP 113788HR 8766SAO 52623PPM 63742WDS 23026+4245[ 10] Database references SIMBAD 2 And 2 And A 2 And B
Alight curve for 2 Andromedae, plotted fromTESS [ 11] 2 Andromedae , abbreviated2 And , is abinary star [ 3] constellation ofAndromeda .2 Andromedae is theFlamsteed designation . It is a faint star system but visible to the naked eye with a combinedapparent visual magnitude of 5.09.[ 2] parallax shift ofmas [ 1] light years away. The binary nature of the star was discovered by American astronomerSherburne Wesley Burnham atLick Observatory in 1889.[ 12] period of 74 years with a higheccentricity of 0.8.[ 3]
The magnitude 5.26[ 3] A-type main-sequence star based on astellar classification of A1V[ 4] [ 3] main sequence .[ 7] Lambda Boötis star , but this was ruled out by Paunzen et al. (2003) as it doesn't match the typical characteristics of these objects.[ 13] infrared excess , it is ashell star that displays varyingabsorption features due to circumstellar dust grains. This may indicate it has an orbitingdebris disk containing gas that is being viewed edge-on.[ 14] projected rotational velocity of 212 km/s.[ 8]
The magnitude 7.43[ 3] variable star and may be aDelta Scuti variable .[ 3] ellipsoidal variable with abrown dwarf companion.[ 7] F-type main-sequence star with a class of F1V/F4.[ 3]
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