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Mu Arae





Mu Arae
A relatively nearby, Sun-like star in the constellation Ara around which three planets have been discovered. One of these, the discovery of which was announced on Aug. 25, 2004, is only about 14 times the mass of Earth, or about one-third the mass of Uranus. However, it is so close to the central star that its surface temperature is expected to be over 1,100°C.

Mu Arae is believed to be somewhat older than the Sun and moving into the subgiant phase of its evolution. Its metallicity is greater than that of the Sun.


Host star
distance 49.8 0.6 light-years (15.3 0.2 pc)
spectral type G3 IV-V
apparent magnitude 5.12
mass 1.08
luminosity 1.7
radius 1.32
position R.A. 17h 44m 08.7s, Dec. -51° 50' 03"
Other designations HR 6585, HD 160691, Gl 691,
HIP 86796, SAO 244981


Planets
  d b c
mass >0.044 MJupiter (14 MEarth) >1.67 0.1 MJupiter >3.1 0.71 MJupiter
semimajor axis 0.09 AU (13.5 million km, 8.4 million miles) 1.5 0.02 AU (224 million km, 93 million miles) 4.7 AU (702 million km, 291 million miles)
orbital period 9.55 0.03 days 654.5 days (1.8 years) 2986 30 days (8.2 years)
eccentricity 0.0 0.31 0.57 0.1
discovery 2004, Santos, Bouchy et al 2002, Marcy, Butler et al 2002, Marcy, Butler et al
method radial velocity radial velocity radial velocity


Related categories

   • NOTABLE STARS
   • EXTRASOLAR PLANETS AND SUBSTELLAR OBJECTS