η Arietis
Location of η Arietis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aries
Right ascension 02h 12m 48.08568s[1]
Declination +21° 12′ 39.5776″[1]
Apparent magnitude (V) 5.231[2]
Characteristics
Spectral type F5 V[3]
U−B color index –0.04[4]
B−V color index +0.44[4]
Astrometry
Radial velocity (Rv)+4.5[2] km/s
Proper motion (μ) RA: +163.917[1] mas/yr
Dec.: +5.000[1] mas/yr
Parallax (π)33.3383 ± 0.1196 mas[1]
Distance97.8 ± 0.4 ly
(30.0 ± 0.1 pc)
Absolute magnitude (MV)+2.93[2]
Details
Mass1.21[5] M☉
Radius0.98[6] R☉
Surface gravity (log g)4.01[3] cgs
Temperature6,380[3] K
Metallicity [Fe/H]–0.35[3] dex
Rotational velocity (v sin i)9[7] km/s
Age2.6 Gyr[2]
3.98[5] Gyr
Other designations
η Ari, 17 Arietis, BD+20 348, GJ 1043, HD 13555, HIP 10306, HR 646, SAO 75204[4]
Database references
SIMBADdata

Eta Arietis, Latinized from η Arietis, is the Bayer designation for a star in the northern constellation of Aries. It is dimly visible to the naked eye with an apparent visual magnitude of 5.231.[2] With an annual parallax shift of 33.34 mas,[1] the distance to this star is approximately 97.8 light-years (30.0 parsecs). It is drifting further away with a radial velocity of +4.5 km/s.[2]

This is an F-type main sequence star with a stellar classification of F5 V.[3] It is younger than the Sun at an age of about 2.6 billion years.[2] The effective temperature of the outer atmosphere is 6,380 K,[3] giving it the yellow-white-hued glow of an F-type star. Eta Arietis was examined using the HARPS instrument for radial velocity variations that may be caused by an orbiting companion, but no signal was detected.[8] Nor has an infrared excess been detected using the Spitzer Space Telescope, which might otherwise indicate the presence of circumstellar gas or dust.[9]

References

  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e f g Holmberg, J.; Nordström, B.; Andersen, J. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191, S2CID 118577511.
  3. ^ a b c d e f Cenarro, A. J.; et al. (January 2007), "Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters", Monthly Notices of the Royal Astronomical Society, 374 (2): 664–690, arXiv:astro-ph/0611618, Bibcode:2007MNRAS.374..664C, doi:10.1111/j.1365-2966.2006.11196.x, S2CID 119428437.
  4. ^ a b c "eta Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-08-04.
  5. ^ a b Luck, R. Earle (January 2017), "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants", The Astronomical Journal, 153 (1): 19, arXiv:1611.02897, Bibcode:2017AJ....153...21L, doi:10.3847/1538-3881/153/1/21, S2CID 119511744, 21.
  6. ^ Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics, 367 (2): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
  7. ^ Takeda, Yoichi; et al. (February 2005), "High-Dispersion Spectra Collection of Nearby F--K Stars at Okayama Astrophysical Observatory: A Basis for Spectroscopic Abundance Standards", Publications of the Astronomical Society of Japan, 57 (1): 13–25, Bibcode:2005PASJ...57...13T, doi:10.1093/pasj/57.1.13.
  8. ^ Lagrange, A.-M.; et al. (February 2009), "Extrasolar planets and brown dwarfs around A-F type stars. VI. High precision RV survey of early type dwarfs with HARPS", Astronomy and Astrophysics, 495 (1): 335–352, arXiv:0809.4636, Bibcode:2009A&A...495..335L, doi:10.1051/0004-6361:200810105, S2CID 62894956.
  9. ^ Trilling, D. E.; et al. (February 2008), "Debris Disks around Sun-like Stars", The Astrophysical Journal, 674 (2): 1086–1105, arXiv:0710.5498, Bibcode:2008ApJ...674.1086T, doi:10.1086/525514, S2CID 54940779.

External links

Constellation of Aries
Categories