55 Arietis

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]

  1. ^ a b c d e f g h i j k l Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference aass34_1 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference aj74_375 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  5. ^ a b c d e Cite error: The named reference Huang2010 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Eggen1995 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).