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55 Arietis

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55 Arietis
Observation data
Epoch J2000      Equinox J2000
Constellation Aries
Right ascension 03h 09m 36.74277s[1]
Declination +29° 04′ 37.4872″[1]
Apparent magnitude (V) 5.72[2]
Characteristics
Spectral type B8 III[3]
U−B color index –0.15[2]
B−V color index +0.115±0.005[4]
Astrometry
Radial velocity (Rv)−2.0±4.3[4] km/s
Proper motion (μ) RA: +19.192[1] mas/yr
Dec.: −12.057[1] mas/yr
Parallax (π)3.5853 ± 0.1194 mas[1]
Distance910 ± 30 ly
(279 ± 9 pc)
Absolute magnitude (MV)−1.75[4]
Details
Mass4.1[5] M
Radius9.49+0.32
−0.56
[1] R
Luminosity326±13[1] L
Surface gravity (log g)2.948±0.023[5] cgs
Temperature7,961+246
−128
[1] K
Rotational velocity (v sin i)196±10[5] km/s
Other designations
55 Ari, BD+28°499, FK5 1088, GC 3762, HD 19548, HIP 14677, HR 944, SAO 75757[6]
Database references
SIMBADdata

55 Arietis is a single[7] star in the northern zodiac constellation of Aries. 55 Arietis is the Flamsteed designation. It is faintly visible to the naked eye as a dim, blue-white hued point of light with an apparent visual magnitude of 5.72.[2] Based upon an annual parallax shift of 3.6 mas,[1] it is approximately 910 light-years (280 parsecs) distant from Earth, give or take a 30 light-year margin of error. Eggen (1995) listed it as a proper motion candidate for membership in the IC 2391 supercluster.[8] It may be a runaway star, having a peculiar velocity of 25.9+3.9
−6.1
 km/s
relative to its neighbors.[9]

The spectrum of this star matches a B-type giant with a stellar classification of B8 III.[3] It has a high rate of spin, showing a projected rotational velocity of 196 km/s.[5] The star has 4.1[5] times the mass of the Sun but 9.5[1] times the Sun's radius. It is radiating 326[1] times as much luminosity as the Sun from its photosphere at an effective temperature of 7,961 K.[1]

References

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  1. ^ a b c d e f g h i j k l 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 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series, 34: 1–49, Bibcode:1978A&AS...34....1N.
  3. ^ a b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
  4. ^ a b c Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  5. ^ a b c d e Huang, W.; et al. (2010), "A Stellar Rotation Census of B Stars: From ZAMS to TAMS", The Astrophysical Journal, 722 (1): 605–619, arXiv:1008.1761, Bibcode:2010ApJ...722..605H, doi:10.1088/0004-637X/722/1/605, S2CID 118532653.
  6. ^ "55 Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-07-31.
  7. ^ 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  8. ^ Eggen, Olin J. (December 1995), "Reality Tests of Superclusters in the Young Disk Population", Astronomical Journal, 110: 2862, Bibcode:1995AJ....110.2862E, doi:10.1086/117734.
  9. ^ Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
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