HD 90089

HD 90089
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 10h 31m 04.7079s[1]
Declination +82° 33′ 31.146″[1]
Apparent magnitude (V) 5.252±0.009[2]
Characteristics
Spectral type F4 V kF2 mF2[3]
U−B color index –0.05[4]
B−V color index 0.37[4]
Astrometry
Radial velocity (Rv)7.9±0.9[5] km/s
Proper motion (μ) RA: –86.133[1] mas/yr
Dec.: +19.832[1] mas/yr
Parallax (π)43.4367 ± 0.5983 mas[1]
Distance75 ± 1 ly
(23.0 ± 0.3 pc)
Absolute magnitude (MV)3.60[6]
Details
Mass1.29[7] M☉
Radius1.40+0.03
−0.06[8] R☉
Luminosity3.36±0.02[8] L☉
Surface gravity (log g)4.43±0.14[7] cgs
Temperature6,602+159
−69[8] K
Metallicity [Fe/H]–0.26[2] dex
Rotational velocity (v sin i)56.2[2] km/s
Age1.074[7] Gyr
Other designations
BD+83°297, FK5 911, GJ 392.1, HD 90089, HIP 51502, HR 4084, SAO 1714, WDS J10311+8234A
Database references
SIMBADdata

HD 90089 (HR 4084; Gliese 392.1) is a star located in the northern circumpolar constellation Camelopardalis. With an apparent magnitude of 5.25,[2] it is faintly visible to the naked eye under ideal conditions. This star is located relatively close at a distance of 75 light years,[8] but is drifting away at a rate of almost 8 km/s.[5]

HD 90089 is an F4 main-sequence star with the calcium K-line and metallic lines of an F2 star.[3] Although the spectral type is of a form that would indicate an Am star, it is not listed in any of the major catalogues of chemically peculiar stars.[9] At present it has 1.29 times the mass of the Sun[7] and 1.4 times its radius. It radiates at 3.36 times the luminosity of the Sun from its photosphere at an effective temperature of 6,602 K,[8] which gives it a yellowish-white hue.

HD 90089's exact age depends on the method, with X-ray giving it a young age of only 300 million years.[2] David et al. gave it an age of 1.1 billion years,[7] significantly older than the previous solution; it spins rapidly with a projected rotational velocity of 56.2 km/s,[2] and has an M0 companion separated 13" away[10] and at approximately the same distance.[11]

An infrared excess has been detected around this star, most likely indicating the presence of a circumstellar disk at a radius of 145 AU. The temperature of this dust is 30 K.[2]

  1. ^ a b c d e Cite error: The named reference dr3a was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference aa555_A11 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Grey2003 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Johnson1966 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Reiners2006 was invoked but never defined (see the help page).
  7. ^ a b c d e Cite error: The named reference David2015 was invoked but never defined (see the help page).
  8. ^ a b c d e Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference renson2009 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Mason2001 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference dr3b was invoked but never defined (see the help page).