Epsilon Pyxidis

Epsilon Pyxidis
Location of ε Pyxidis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Pyxis
Right ascension 09h 09m 56.41024s[1]
Declination −30° 21′ 55.4460″[1]
Apparent magnitude (V) +5.60[2]
Characteristics
Spectral type A4 IV[3]
U−B color index +0.16[2]
B−V color index +0.16[2]
Astrometry
Radial velocity (Rv)−9.7±0.3[4] km/s
Proper motion (μ) RA: −1.93[1] mas/yr
Dec.: −48.99[1] mas/yr
Parallax (π)15.39 ± 0.30 mas[1]
Distance212 ± 4 ly
(65 ± 1 pc)
Absolute magnitude (MV)+2.00[5]
Details
ε Pyx A
Mass2.07[6] M☉
Luminosity19[7] L☉
Surface gravity (log g)3.26[8] cgs
Temperature6368±1806[8] K
Metallicity [Fe/H]+0.04[8] dex
Rotational velocity (v sin i)108.3±0.3[9] km/s
Age560[6] Myr
Other designations
ε Pyx, CPD−29° 2933, FK5 1241, HD 78922, HIP 45001, HR 3644, SAO 200047, WDS J09099-3022A[10]
Database references
SIMBADdata

Epsilon Pyxidis (ε Pyxidis) is quadruple[11] star system in the southern constellation of Pyxis. It is faintly visible to the naked eye, having a combined apparent visual magnitude of +5.60.[2] Based upon an annual parallax shift of 15.39 mas as seen from Earth,[1] it is located around 212 light years from the Sun. The system is deemed to be a member of the Sirius supercluster of stars that share a common motion through space.[5]

The primary, component A, is a white-hued A-type subgiant star with a stellar classification of A4 IV.[3] It is a microvariable, showing a 0.0056 change in magnitude with a frequency of 0.16245 times per day.[12] Epsilon Pyxidis has been catalogued as an Am star,[2] although this remains uncertain.[13] It has double[6] the mass of the Sun and radiates 19[7] times the Sun's luminosity from its photosphere at an effective temperature of 6,368 K.[8]

In addition to a close companion of unknown type at an angular separation of 0.17 arc seconds, the primary shares an orbit with a binary star system, components B and C, that lie at an angular separation of 17.8 arc seconds. At the estimated distance of this system, this corresponds to a projected separation of around 1,150 AU.[6] The B/C pair consist of visual magnitude 10.5 and 10.8 stars with a mean separation of 0.3 arc seconds.[11] They have estimated mass of 90% and 95% that of the Sun, respectively.[6]

  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 e Cite error: The named reference Mendoza1978 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1979 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Eggen1998 was invoked but never defined (see the help page).
  6. ^ a b c d e Cite error: The named reference DeRosa2014 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference Casagrande2011 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Diaz2011 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference koen2002 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Renson2009 was invoked but never defined (see the help page).