Mu Arietis

μ Arietis
Location of μ Arietis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aries
Right ascension 02h 42m 21.93980s[1]
Declination +20° 00′ 41.2612″[1]
Apparent magnitude (V) 5.74[2] (6.38/8.38/6.72/12.2)[3]
Characteristics
Spectral type A0 Vp + F2 V + A1 V[3]
U−B color index –0.03[4]
B−V color index –0.02[4]
Astrometry
Radial velocity (Rv)–6.0[5] km/s
Proper motion (μ) RA: +27.68[1] mas/yr
Dec.: –47.64[1] mas/yr
Parallax (π)9.64 ± 0.88 mas[1]
Distance340 ± 30 ly
(104 ± 9 pc)
Absolute magnitude (MV)+0.41[6]
Orbit[7]
Period (P)8.845 ± 0.046 yr
Semi-major axis (a)0.0563 ± 0.0008″
Eccentricity (e)0.337 ± 0.023
Inclination (i)71.2 ± 1.1°
Longitude of the node (Ω)101.0 ± 1.0°
Periastron epoch (T)B 1981.099 ± 0.063
Argument of periastron (ω)
(secondary)		92.3 ± 1.7°
Details
Mass3.4 ± 1.7 (Aa) / 2.1 ± 1.7 (Ab)[7] M☉
Luminosity71.7[6] L☉
Rotational velocity (v sin i)175[8] km/s
Other designations
μ Ari, 34 Arietis, BD+19 403, HD 16811, HIP 12640, HR 793, SAO 93062.[9]
Database references
SIMBADdata

Mu Arietis, Latinized from μ Arietis, is the Bayer designation for a star system in the northern constellation of Aries. It is approximately 340 light-years (100 parsecs) distant from Earth, give or take a 30 light-year margin of error, and has a combined apparent visual magnitude of 5.74.[2] According to the Bortle Dark-Sky Scale, this means it is faintly visible to the naked eye from dark suburban skies.

At the heart of this system is a close orbiting pair consisting of a magnitude 6.38 A-type main sequence star with a stellar classification of A0 Vp and a magnitude 8.38 F-type main sequence companion with a classification of F2 V. These two components have an angular separation of 0.04 arcseconds. A third component, consisting of a magnitude 6.72 star with a classification of A1 V, is orbiting the inner pair with a period of 8.845 years and an eccentricity of 0.34. A smaller fourth component, at an angular separation of 19.1 arcseconds, has a magnitude of 12.2.[3]

  1. ^ a b c d e Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference aaass89_2_415 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference mnras389_2_869 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference atao6_148 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference rob135_385 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b Mason, Brian D. (1997). "Binary Star Orbits from Speckle Interferometry. XI. Orbits of Twelve Lunar Occultation Systems". The Astronomical Journal. 114: 808. Bibcode:1997AJ....114..808M. doi:10.1086/118514.
  8. ^ Cite error: The named reference aaa463_2_671 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).