Astronomy:Eta Leporis

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Short description: Star in the constellation of Lepus
η Leporis
Observation data
Equinox J2000.0]] (ICRS)
Constellation Lepus
Right ascension  05h 56m 24.29300s[1]
Declination −14° 10′ 03.7189″[1]
Apparent magnitude (V) 3.72[2]
Characteristics
Spectral type F2 V[3]
U−B color index +0.01[2]
B−V color index +0.33[2]
R−I color index +0.16[4]
Astrometry
Radial velocity (Rv)−1.6±0.2[5] km/s
Proper motion (μ) RA: −42.06[1] mas/yr
Dec.: +139.26[1] mas/yr
Parallax (π)67.21 ± 0.25[1] mas
Distance48.5 ± 0.2 ly
(14.88 ± 0.06 pc)
Absolute magnitude (MV)+2.85[6]
Details
Mass1.42[5] M
Radius1.52[7] R
Luminosity6.03[6] L
Surface gravity (log g)4.13[5] cgs
Temperature6,899±80[5] K
Metallicity [Fe/H]−0.19[5] dex
Rotational velocity (v sin i)26[8] km/s
Age1.80[5] Gyr
Other designations
η Lep, 16 Leporis, BD−14° 1286, FK5 226, GC 7492, GJ 225, HD 40136, HIP 28103, HR 2085, SAO 150957, PPM 216474[9]
Database references
SIMBADdata

Eta Leporis, Latinised from η Leporis, is a single,[10] yellow-white-hued star in the southern constellation of Lepus, the hare. It is visible to the naked eye with an apparent visual magnitude of approximately 3.72.[2] The annual parallax shift of 67.21 mas yields a distance estimate of 49 light-years. It is moving closer to the Sun with a radial velocity of −1.6 km/s.[5]

This is an ordinary F-type main-sequence star with a stellar classification of F2 V.[3] It is about 1.8[5] billion years old and spinning with a projected rotational velocity of 26 km/s.[8] The star has 1.4[5] times the mass of the Sun and 1.5[7] times the Sun's radius. It shines with six[6] times the Sun's luminosity, which is being radiated from its photosphere at an effective temperature of around 6,899 K.[5] Using the IRS instrument on the Spitzer Space Telescope, excess infrared emission has been observed from the star, which can be modeled by a dust disk extending from 1 to 16 astronomical units from Eta Leporis.[11]

References

  1. 1.0 1.1 1.2 1.3 1.4 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. http://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html.  Vizier catalog entry
  2. 2.0 2.1 2.2 2.3 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 Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (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): 161–170. doi:10.1086/504637. Bibcode2006AJ....132..161G. 
  4. Hoffleit, D.; Warren, Jr., W. H.. The Bright Star Catalogue (5th Revised (Preliminary Version) ed.). HR 2085, database entry, CDS ID V/50. Accessed on line February 3, 2011.
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 Casagrande, L. et al. (June 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey". Astronomy and Astrophysics 530: A138. doi:10.1051/0004-6361/201016276. Bibcode2011A&A...530A.138C. 
  6. 6.0 6.1 6.2 Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A.  Vizier catalog entry
  7. 7.0 7.1 Rhee, Joseph H. et al. (May 2007), "Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs", The Astrophysical Journal 660 (2): 1556–1571, doi:10.1086/509912, Bibcode2007ApJ...660.1556R 
  8. 8.0 8.1 Zorec, J.; Royer, F. (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. 
  9. "eta Lep". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=eta+Lep. 
  10. Eggleton, P. P.; Tokovinin, A. A. (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. Lawler, S. M. et al. (November 2009). "Explorations Beyond the Snow Line: Spitzer/IRS Spectra of Debris Disks Around Solar-type Stars". The Astrophysical Journal 705 (1): 89–111. doi:10.1088/0004-637X/705/1/89. Bibcode2009ApJ...705...89L.  See Table 7.