2 Equulei

2 Equulei
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Equuleus
Right ascension 21h 02m 12.50262s[1]
Declination +07° 10′ 47.1545″[1]
Apparent magnitude (V) 6.698[2] (7.41 + 7.64)[3]
Characteristics
Spectral type F6V[4]
Astrometry
Radial velocity (Rv)−4.8±1.6[5] km/s
Absolute magnitude (MV)2.16±0.18[2]
A
Proper motion (μ) RA: −9.184[6] mas/yr
Dec.: −12.915[6] mas/yr
Parallax (π)8.8125 ± 0.2481 mas[6]
Distance370 ± 10 ly
(113 ± 3 pc)
B
Proper motion (μ) RA: −4.238[7] mas/yr
Dec.: −17.934[7] mas/yr
Parallax (π)8.5577 ± 0.0298 mas[7]
Distance381 ± 1 ly
(116.9 ± 0.4 pc)
Details
2 Equ A
Mass1.73[5] M☉
Radius3.37[8] R☉
Luminosity13.087[8] L☉
Surface gravity (log g)4.05[5] cgs
Temperature6,561±80[5] K
Metallicity [Fe/H]0.17[5] dex
Age1.6[5] Gyr
2 Equ B
Radius2.74[9] R☉
Luminosity10.828 L☉
Temperature6,330[9] K
Other designations
λ Equ, 2 Equulei, BD+06°4731, HD 200256, HIP 103813, LTT 16227, SAO 126482[10]
Database references
SIMBADdata

2 Equulei is a double star system in the constellation of Equuleus.

The primary component of the 2 Equulei pair is an F-type main sequence star. As of 2015, the secondary had an angular separation of 2.90 arc seconds along a position angle of 213° from the primary.[3] They form a common proper motion pair, two stars at approximately the same distance and moving in the same direction.[4] Gaia EDR3 gives them parallaxes of 8.8125±0.2471 mas and 8.5577±0.0298 mas respectively, although they are flagged as potentially unreliable.[6][7] These parallaxes correspond to a distance of around 380 ly, in contrast to the Hipparcos distance of 260±20 ly for the two stars as a pair.[1]

2 Equulei has been referred to in some sources as λ (Lambda) Equulei, although it was not given that designation by Bayer.

  1. ^ a b c Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Holmberg2009 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference abt was invoked but never defined (see the help page).
  5. ^ a b c d e f Cite error: The named reference Casagrande2011 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference edr3a was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference edr3b was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference dr2a was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference dr2b was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).