Kappa Piscium

Kappa Piscium
Location of κ Piscium (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Pisces
Right ascension 23h 26m 55.95586s[1]
Declination +01° 15′ 20.1900″[1]
Apparent magnitude (V) 4.94[2]
Characteristics
Spectral type A2 Vp SrCrSi[3]
U−B color index −0.03[2]
B−V color index +0.04[2]
Variable type α2 CVn[4]
Astrometry
Proper motion (μ) RA: +86.68[1] mas/yr
Dec.: −94.29[1] mas/yr
Parallax (π)21.25 ± 0.29 mas[1]
Distance153 ± 2 ly
(47.1 ± 0.6 pc)
Absolute magnitude (MV)+1.59[5]
Details[6]
Mass2.62 M☉
Radius1.86[7] R☉
Luminosity30[8] L☉
Surface gravity (log g)4.46 cgs
Temperature10,961±373 K
Metallicity [Fe/H]+0.74[5] dex
Rotational velocity (v sin i)34 km/s
Age157 Myr
Other designations
κ Psc, 8 Piscium, BD+00° 4998, FK5 884, HD 220825, HIP 115738, HR 8911, SAO 128186, WDS J23269+0115A[9]
Database references
SIMBADdata

Kappa Piscium (κ Piscium) is a solitary,[10] white-hued star in the zodiac constellation of Pisces. It is visible to the naked eye with an apparent visual magnitude of 4.94,[2] forming the southeastern corner of the "Circlet" asterism in Pisces. Based upon a measured annual parallax shift of 21.25 mas as seen from Earth,[1] it is located about 153 light years distant from the Sun. Appearing as a single point in the sky, it is easily split when viewed with a pair of binoculars, and displays three components. Kappa Piscium has an apparent magnitude of 4.87 at maximum brightness and 4.95 at minimum brightness,[4] while the visual companions have apparent magnitudes of 9.96 and 11.20.[11]

A light curve for Kappa Piscium, plotted from TESS data[12]

This is an A-type main-sequence star with a stellar classification of A2 Vp SrCrSi.[3] The suffix designation indicates it is a "chemically peculiar" Ap star[7] that displays abnormal abundances of silicon, strontium, and chromium. It is an Alpha2 Canum Venaticorum variable[4] with a weak[7] active magnetic field that causes it to fluctuate by 0.01 to 0.1 in magnitude as it rotates. It shows many lines of uranium, and possibly the rare element holmium in its spectrum. Its uranium and osmium content could have been provided by a nearby supernova.[13] Compared to the Sun, it is deficient in oxygen relative to the magnesium abundance.

This star is a candidate member of the AB Doradus moving group, an association of stars with similar ages that share a common heading through space.[8]

  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 Johnson1966 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference abt1995 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Glagolevskij2006 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference McCarthy2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference MAST was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Jorgensen2005 was invoked but never defined (see the help page).