HD 233731

HD 233731
Observation data
Epoch J2000      Equinox J2000
Constellation Ursa Major
Right ascension 10h 22m 43.5923s[1]
Declination +50° 07′ 42.062″[1]
Apparent magnitude (V) 9.732[2]
Characteristics
Spectral type G5V[3]
B−V color index 0.86[3]
Astrometry
Radial velocity (Rv)12.86(15)[1] km/s
Proper motion (μ) RA: −26.110(14) mas/yr[1]
Dec.: 83.806(16) mas/yr[1]
Parallax (π)12.2731 ± 0.0155 mas[1]
Distance265.7 ± 0.3 ly
(81.5 ± 0.1 pc)
Absolute magnitude (MV)5.22±0.14[2]
Details[3]
Mass0.936+0.028
−0.033
 M
Radius1.062+0.046
−0.013
 R
Luminosity0.77±0.09[2] L
Surface gravity (log g)4.357+0.039
−0.005
 cgs
Temperature5,314±50 K
Metallicity [Fe/H]0.30±0.09 dex
Rotation28.7±0.4 d
Rotational velocity (v sin i)1.65±0.26 km/s
Age9.0+1.4
−2.2
 Gyr
[3]
12.4±2.6[2] Gyr
Other designations
HAT-P-22, Gaia DR2 846946629987527168, HD 233731, TYC 3441-925-1, GSC 03441-00925, 2MASS J10224361+5007420[4]
Database references
SIMBADdata

HD 233731, or HAT-P-22, is a suspected multiple star system in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye, having an apparent visual magnitude of 9.732.[2] This system is located at a distance of 267 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +13 km/s.[1]

The stellar classification of the primary is G5V,[3] matching an ordinary G-type main-sequence star. The star has a low level of stellar activity with an estimated age of 9 to 12 billion years old. Its metallicity is twice that of the Sun, unusual for its advanced age.[3] HD 233731 has a similar mass and radius as the Sun, and is spinning with a rotation period of 28.7 days.[3] It is radiating 77%[2] of the luminosity of the Sun from its photosphere at an effective temperature of 5314 K.[3]

A faint stellar companion (2MASS J10224397+5007504) with a red hue is located at an angular separation of 9 arcseconds from the primary.[2] In 2015, a spectroscopic stellar companion was reported with a semimajor axis of less than 33 AU. This star has an effective temperature of 4,000+250
−400
 K
with a mass of 0.63+0.07
−0.17
 M
.[5]

  1. ^ a b c d e f Cite error: The named reference Gaia DR3 was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference Bakos_et_al_2010 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h Cite error: The named reference Mancini_et_al_2018 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Piskorz_et_al_2015 was invoked but never defined (see the help page).