Pi Andromedae

Pi Andromedae
Diagram showing star positions and boundaries of the Andromeda constellation and its surroundings
Location of π Andromedae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension 00h 36m 52.85132s[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 (Rv)+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]
Distance580 ± 20 ly
(177 ± 5 pc)
Orbit[3]
Period (P)143.6 days
Eccentricity (e)0.56
Details
Luminosity1,136[6] L☉
Surface gravity (log g)4.10[4] cgs
Temperature15,276[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
SIMBADdata
π Andromedae in optical light

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.

  1. ^ a b c d e f Cite error: The named reference Gaia EDR3 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference clpl4_99 was invoked but never defined (see the help page).
  3. ^ a b c d e f Cite error: The named reference mnras389_2_869 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference mnras374_2_664 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference gcrv was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference apj573_1_359 was invoked but never defined (see the help page).