23 Ursae Majoris

23 Ursae Majoris
Location of 23 Ursae Majoris (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Ursa Major
Right ascension 09h 31m 31.70873s[1]
Declination +63° 03′ 42.7013″[1]
Apparent magnitude (V) +3.65[2] / +9.0
Characteristics
Spectral type F0IV[3]
B−V color index 0.360±0.015[2]
Astrometry
Radial velocity (Rv)−10.4±0.7[2] km/s
Proper motion (μ) RA: +107.99[1] mas/yr
Dec.: + 27.15[1] mas/yr
Parallax (π)41.99 ± 0.16 mas[1]
Distance77.7 ± 0.3 ly
(23.82 ± 0.09 pc)
Details
23 UMa A
Mass1.862[3] M☉
Radius2.90±0.03[3] R☉
Luminosity14.8±0.1[3] L☉
Temperature6,651±27[3] K
Metallicity [Fe/H]0.17[3] dex
Age1.3[3] Gyr
Other designations
h UMa, 23 UMa, BD+63°845, FK5 355, GJ 3534, HD 81937, HIP 46733, HR 3757, SAO 14908, CCDM J09315+6303A/B[4]
Database references
SIMBADdata

23 Ursae Majoris, or 23 UMa, is a binary star system in the constellation Ursa Major,[4] located is approximately 77.7 light years from the Sun.[1] It has the Bayer designation h Ursae Majoris; 23 Ursae Majoris is the Flamsteed designation. The system is visible to the naked eye as a yellow-white hued star with an apparent visual magnitude of +3.65.[2] It is moving closer to the Earth with a heliocentric radial velocity of −10 km/s.[2]

The primary component is a yellow-white F-type subgiant with an apparent magnitude of +3.65. It has 1.9 times the Sun's mass, 2.9 times the Sun's radius and is emitting 15 times the luminosity of the Sun[5] at an effective temperature of 6,651 K.[3] Orbiting at an angular separation of 22.7 arcseconds is the 9th magnitude secondary companion. There is a magnitude +10.5 optical companion at an angular separation of 99.6 arcseconds.

  1. ^ a b c d e f Cite error: The named reference hipparcos2007 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h Cite error: The named reference apj771_1_40 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Simbad was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference apj746_1_101 was invoked but never defined (see the help page).