Xi Piscium

Xi Piscium
Location of ξ Piscium (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Pisces
Right ascension 01h 45m 23.63185s[1]
Declination +09° 09′ 27.8530″[1]
Apparent magnitude (V) 4.60[2]
Characteristics
Spectral type K0 III[3]
U−B color index +0.74[2]
B−V color index +0.95[2]
Astrometry
Radial velocity (Rv)+26.13[3] km/s
Proper motion (μ) RA: +72.98[1] mas/yr
Dec.: +39.30[1] mas/yr
Parallax (π)11.67 ± 0.67 mas[1]
Distance280 ± 20 ly
(86 ± 5 pc)
Absolute magnitude (MV)+0.78[4]
Orbit[5]
Period (P)1672.4±1.4 d
Eccentricity (e)0.18±0.03
Periastron epoch (T)2437651 ± 40 JD
Argument of periastron (ω)
(secondary)		71±9°
Semi-amplitude (K1)
(primary)		4.64±0.14 km/s
Details
ξ Psc A
Mass2.00[3] M☉
Radius9[6] R☉
Luminosity45.7[3] L☉
Surface gravity (log g)2.8[6] cgs
Temperature4,947±25[3] K
Metallicity [Fe/H]−0.11[6] dex
Rotational velocity (v sin i)0.0[6] km/s
Age1.22[3] Gyr
Other designations
ξ Psc, ξ Psc, 111 Piscium, BD+02° 290, FK5 65, HD 11559, HIP 8833, HR 549, SAO 110206, WDS J02020+246AB[7]
Database references
SIMBADdata

Xi Piscium (ξ Piscium) is an orange-hued binary star[8] system in the zodiac constellation of Pisces. In 1690, the astronomer Johannes Hevelius in his Firmamentum Sobiescianum regarded the constellation Pisces as being composed of four subdivisions. Xi Piscium was considered to be part of the Linum Austrinum, the South Cord.[9] The star is visible to the naked eye, having an apparent visual magnitude of 4.60.[2] Based upon an annual parallax shift of 11.67 mas as seen from Earth,[1] it is located about 280 light years from the Sun. It is moving away from the Sun, having a radial velocity of +26 km/s.[3]

This is a single-lined spectroscopic binary system with an orbital period of 4.6 years and an eccentricity of around 0.18.[5] The spectroscopic binary nature of this star was discovered in 1901 by William Wallace Campbell using the Mills spectrograph at the Lick Observatory.[10] The visible component is an evolved K-type giant star with a stellar classification of K0 III.[3] It is a red clump star, which indicates it is generating energy through helium fusion at its core.[11]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Argue1966 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h Cite error: The named reference Luck2015 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Pourbaix2004 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Massarotti2008 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Griffin1981 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Hevelius was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Campbell1901 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Tautvaisiene2010 was invoked but never defined (see the help page).