Astronomy:Eta1 Pictoris

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Short description: Star in the constellation Pictor


Eta1 Pictoris
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pictor
Right ascension  05h 02m 48.68641s[1]
Declination −49° 09′ 05.0644″[1]
Apparent magnitude (V) +5.37[2]
Characteristics
Spectral type F5 V[3]
U−B color index −0.01[2]
B−V color index +0.43[2]
Astrometry
Radial velocity (Rv)21.4±2.8[4] km/s
Proper motion (μ) RA: −43.67[1] mas/yr
Dec.: +27.37[1] mas/yr
Parallax (π)38.35 ± 0.18[1] mas
Distance85.0 ± 0.4 ly
(26.1 ± 0.1 pc)
Absolute magnitude (MV)3.28[5]
Details
Mass1.37[6] M
Radius1.1[7] R
Luminosity3.69[8] L
Surface gravity (log g)4.17[6] cgs
Temperature6,631±225[6] K
Metallicity [Fe/H]−0.05[3] dex
Rotational velocity (v sin i)22.7±1.1[5] km/s
Age2.15[6] Gyr
Other designations
η1 Pic, CD−49° 1541, GJ 187, HD 32743, HIP 23482, HR 1649, SAO 217140[9]
Database references
SIMBADdata

η1 Pictoris, Latinised as Eta1 Pictoris, is a solitary[10] star in the southern constellation of Pictor. It is faintly visible to the naked eye with an apparent visual magnitude of +5.37.[2] Based upon an annual parallax shift of 38.35 mas as seen from the Earth,[1] the system is located 85 light years from the Sun. The star made its closest approach to the Sun about 1.1 million years ago with a perihelion passage of about 24 ly (7.5 pc).[11]

This is an F-type main sequence star with a stellar classification of F5 V[3] and it is chromospherically active.[3] It is an estimated 2.15[6] billion years old and is spinning with a projected rotational velocity of 22.7 km/s.[5] The star has 1.4[6] times the mass of the Sun and about 1.1[7] times the Sun's radius. It is radiating 3.7[8] times the Sun's luminosity from its photosphere at an effective temperature of roughly 6,631 K.[6]

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 2.3 Cousins, A. W. J. (1973), "UBV photometry of some southern stars", Monthly Notes of the Astronomical Society of Southern Africa 32: 11, Bibcode1973MNSSA..32...11C. 
  3. 3.0 3.1 3.2 3.3 Gray, R. O. et al. (2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal 132 (1): 161–70, doi:10.1086/504637, Bibcode2006AJ....132..161G. 
  4. De Bruijne, J. H. J.; Eilers, A.-C. (2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: A61, doi:10.1051/0004-6361/201219219, Bibcode2012A&A...546A..61D. 
  5. 5.0 5.1 5.2 Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics 542: A116, doi:10.1051/0004-6361/201118724, Bibcode2012A&A...542A.116A. 
  6. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 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. 
  7. 7.0 7.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  8. 8.0 8.1 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. 
  9. "eta01 Pic -- Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/simbad/sim-id?Ident=eta01+Pic, retrieved 2017-06-22. 
  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. 
  11. Bailer-Jones, C. A. L. (March 2015), "Close encounters of the stellar kind", Astronomy & Astrophysics 575: 13, doi:10.1051/0004-6361/201425221, A35, Bibcode2015A&A...575A..35B.