20 Aquarii

20 Aquarii
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 21h 24m 51.67515s[1]
Declination −03° 23′ 54.0858″[1]
Apparent magnitude (V) 6.38[2]
Characteristics
Spectral type F0 V[3] or F0 III[4]
B−V color index 0.334±0.002[2]
Astrometry
Radial velocity (Rv)−23.2±2.9[5] km/s
Proper motion (μ) RA: −6.125[1] mas/yr
Dec.: −49.515[1] mas/yr
Parallax (π)15.3426 ± 0.0730 mas[1]
Distance213 ± 1 ly
(65.2 ± 0.3 pc)
Absolute magnitude (MV)2.37[2]
Details
Mass1.52[6] M☉
Luminosity9.38[2] L☉
Surface gravity (log g)4.17[6] cgs
Temperature7,314±249[6] K
Rotational velocity (v sin i)92[7] km/s
Age761[6] Myr
Other designations
BD−05° 5444, GC 29976, HD 203843, HIP 105729, HR 8192, SAO 145376[8]
Database references
SIMBADdata

20 Aquarii, abbreviated 20 Aqr, is a star in the constellation Aquarius. 20 Aquarii is the Flamsteed designation. It is a dim star with an apparent visual magnitude of 6.38.[2] Based upon an annual parallax shift of 15.34 mas,[1] it is located 213 light years away but is moving closer to the Earth with a heliocentric radial velocity of −23 km/s.[5] The star is predicted to come to within 110 light-years in around 1.9 million years.[2]

This is an F-type main-sequence star with a stellar classification of F0 V.[3] (Cowley and Fraquelli [1974] had given it a class of F0 III.)[4] It is a suspected[9] chemically peculiar Am star showing metallic lines.[10] It is 761[6] million years old with a high projected rotational velocity of 92 km/s.[7] The star has 1.52[6] times the mass of the Sun and is radiating 9[2] times the Sun's luminosity from its photosphere at an effective temperature of about 7,314 K.[6]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Houk1999 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Cowley1974 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. ^ a b c d e f g Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Royer2002 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD 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 Paunzen2013 was invoked but never defined (see the help page).