Astronomy:Eta Pyxidis

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Short description: White-hued main sequence star in the constellation Pyxis
Eta Pyxidis
Pyxis IAU.svg
Red circle.svg
Location of η Pyxidis (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pyxis
Right ascension  08h 37m 52.15248s[1]
Declination −26° 15′ 18.0063″[1]
Apparent magnitude (V) +5.27[2]
Characteristics
Spectral type A0 V[3]
B−V color index −0.04[2]
Astrometry
Radial velocity (Rv)31.0±4.2[4] km/s
Proper motion (μ) RA: −24.49[1] mas/yr
Dec.: −13.02[1] mas/yr
Parallax (π)14.07 ± 0.21[1] mas
Distance232 ± 3 ly
(71 ± 1 pc)
Absolute magnitude (MV)+0.90[5]
Details
Mass2.51±0.01[6] M
Luminosity42[7] L
Surface gravity (log g)4.33[8] cgs
Temperature11,614±395[8] K
Rotational velocity (v sin i)238[6] km/s
Age67[8] Myr
Other designations
η Pyx, CPD−25° 3792, FK5 2676, HD 73495, HIP 42334, HR 3420, SAO 176189, WDS J08379-2615A[9]
Database references
SIMBADdata

Eta Pyxidis (η Pyxidis) is a solitary,[10] white-hued star in the southern constellation of Pyxis. It is faintly visible to the naked eye with an apparent visual magnitude of +5.27.[2] Based upon an annual parallax shift of 14.07 mas as seen from Earth,[1] this star is located around 232 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.07 due to interstellar dust.[5]

This is an A-type main-sequence star with a stellar classification of A0 V.[3] It is young with an age of around 67[8] million years and is spinning rapidly with a projected rotational velocity of 238 km/s.[6] The star has 2.51[6] times the mass of the Sun and is radiating 42[7] times the Sun's luminosity from its photosphere at an effective temperature of around 11,614 K.[8]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode1988mcts.book.....H. 
  4. de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode2012A&A...546A..61D. 
  5. 5.0 5.1 Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters 38 (11): 694–706, doi:10.1134/S1063773712110035, Bibcode2012AstL...38..694G. 
  6. 6.0 6.1 6.2 6.3 Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  7. 7.0 7.1 McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode2012MNRAS.427..343M. 
  8. 8.0 8.1 8.2 8.3 8.4 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  9. "eta Pyx". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=eta+Pyx. 
  10. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E.