Omega Andromedae

Omega Andromedae
Diagram showing star positions and boundaries of the Andromeda constellation and its surroundings
Location of ω Andromedae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension 01h 27m 39.38072s[1]
Declination +45° 24′ 24.0651″[1]
Apparent magnitude (V) +4.83[2][3]
Characteristics
Spectral type F5 IVe[4] or F3 V + F5 V[5]
U−B color index +0.00[3]
B−V color index +0.42[3]
Astrometry
Radial velocity (Rv)+14.7[2] km/s
Proper motion (μ) RA: 357.564(127)[1] mas/yr
Dec.: −110.039(118)[1] mas/yr
Parallax (π)34.7332 ± 0.1341 mas[1]
Distance93.9 ± 0.4 ly
(28.8 ± 0.1 pc)
Absolute magnitude (MV)+2.57[2]
Details
ω And A
Mass0.963±0.049[5] M☉
Radius2.2[6] R☉
Luminosity7.1[7] L☉
Temperature6,628[7] K
Metallicity [Fe/H]−0.16[2] dex
Rotational velocity (v sin i)57.1[8] km/s
Age2.1[2] Gyr
ω And B
Mass0.860±0.051[5] M☉
Other designations
48 Andromedae, BD+44°307, FK5 1040, HD 8799, HIP 6813, HR 417, SAO 37228, PPM 44006[4]
Database references
SIMBADdata

Omega Andromedae (ω And, ω Andromedae) is the Bayer designation for a slowly co-rotating[failed verification] binary star system[9] in the northern constellation of Andromeda. Parallax measurements made during the Gaia mission make this system to be approximately 93.9 light-years (28.8 parsecs) from Earth. Its apparent visual magnitude is +4.83,[2] which makes it bright enough to be seen with the naked eye.

The primary component has a stellar classification of F5 IVe.[4] The IV luminosity class indicates that it is probably a subgiant star that is in the process of evolving away from the main sequence as the supply of hydrogen at its core depletes. However, Abt (1985) gives a classification of F3 V, suggesting it is an F-type main-sequence star.[5] The measured angular diameter of the primary star is 0.70 ± 0.03 mas.[10] At the system's estimated distance this yields a size of about 2.2 times that of the Sun.[6] It is emitting about seven times solar luminosity from its outer atmosphere at an effective temperature of 6,628 K.[7] This heat gives it the yellow-white-hued glow of an F-type star.[11]

In 2008, the companion star was resolved using adaptive optics at the Lick Observatory. Later observations showed the magnitude difference between the two stars is 3.65 ± 0.03 and they are separated by 0.669 arcsecond.[9] Abt (1985) lists the class as F5 V.[5]

  1. ^ a b c d e Cite error: The named reference Gaia EDR3 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference aaa418_989 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference clpl4_99 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  5. ^ a b c d e Cite error: The named reference Farrington2014 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference lang2006 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference aaa405_723 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference aaa493_3_1099 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference apj698_1_28 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference aaa431_773 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference csiro was invoked but never defined (see the help page).