Astronomy:17 Eridani

From HandWiki

|- ! style="text-align: center; background-color: #FFFFC0;" colspan="2" | Observation data
Equinox J2000.0]] (ICRS) |- style="vertical-align:top" ! style="text-align:left" | Constellation | Eridanus |- style="vertical-align:top"

|- style="vertical-align:top" ! style="text-align:left" | Right ascension |  03h 30m 37.05823s[1] |- style="vertical-align:top" ! style="text-align:left" | Declination | −05° 04′ 30.5239″[1] |- style="vertical-align:top" ! style="text-align:left" | Apparent magnitude (V) | 4.74[2]

|- ! style="background-color: #FFFFC0; text-align: center;" colspan="2"| Characteristics |-

|-

|- style="vertical-align:top" ! style="text-align:left" | Evolutionary stage | main sequence[3] |- style="vertical-align:top" ! style="text-align:left" | Spectral type | B9 III[4] or B9Vs[5] |- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top" ! style="text-align:left" | B−V color index | −0.092±0.008[2] |- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

|- style="vertical-align:top"

AstrometryRadial velocity (Rv)+15.0±4.2[2] km/sProper motion (μ) RA: 14.23[1] mas/yr
Dec.: 7.27[1] mas/yr Parallax (π)8.07 ± 0.20[1] masDistance400 ± 10 ly
(124 ± 3 pc)Absolute magnitude (MV)−0.72[2] DetailsMass3.55±0.04[3] MRadius3.2[6] RLuminosity267.9+15.2
−14.4
[3] LSurface gravity (log g)3.603±0.017[7] cgsTemperature11,143±51[3] KRotational velocity (v sin i)86[3] km/sAge178+10
−9
[8] Myr Other designations

v Eri, 17 Eri, BD−05°674, HD 21790, HIP 16341, HR 1070, SAO 130528[9]

Database referencesSIMBADdata

|}

17 Eridani is a single[10] star in the equatorial constellation of Eridanus. It has the Bayer designation v Eridani, while 17 Eridani is the Flamsteed designation. This object is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.74.[2] It is moving further from the Earth with a heliocentric radial velocity of around +15 km/s.[2]

Houk and Swift (1999) found a stellar classification of B9 III[4] for this star, while Cowley et al. (1969) show B9 Vs.[5] Stellar models suggest this is a main-sequence star,[3] which indicates it is generating energy through hydrogen fusion at its core. It is about 178[8] million years old with 3.55[3] times the mass of the Sun and around 3.2[6] times the size of the Sun. The star is radiating 268[3] times the Sun's luminosity from its photosphere at an effective temperature of 11,143 K.[3] These coordinates are a source for X-ray emission, which may be coming from an unresolved companion.[7]

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. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Zorec, J. et al. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  4. 4.0 4.1 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey 5, Bibcode1999MSS...C05....0H. 
  5. 5.0 5.1 Cowley, A. et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal 74: 375–406, doi:10.1086/110819, Bibcode1969AJ.....74..375C. 
  6. 6.0 6.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367 (2): 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  7. 7.0 7.1 Huang, Wenjin et al. (October 2010), "A Stellar Rotation Census of B Stars: From ZAMS to TAMS", The Astrophysical Journal 722 (1): 605–619, doi:10.1088/0004-637X/722/1/605, Bibcode2010ApJ...722..605H. 
  8. 8.0 8.1 Hubrig, S. et al. (June 2001), "Search for low-mass PMS companions around X-ray selected late B stars", Astronomy and Astrophysics 372: 152–164, doi:10.1051/0004-6361:20010452, Bibcode2001A&A...372..152H. 
  9. "17 Eri". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=17+Eri. 
  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.