Upsilon Aquarii

Not to be confused with U Aquarii.
Upsilon Aquarii
Location of υ Aquarii (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 34m 41.63670s[1]
Declination –20° 42′ 29.5745″[1]
Apparent magnitude (V) +5.21[2]
Characteristics
Spectral type F7 V[3]
B−V color index +0.44[2]
Astrometry
Radial velocity (Rv)−2.28±0.51[1] km/s
Proper motion (μ) RA: +220.383[1] mas/yr
Dec.: –147.225[1] mas/yr
Parallax (π)43.5816 ± 0.1436 mas[1]
Distance74.8 ± 0.2 ly
(22.95 ± 0.08 pc)
Absolute magnitude (MV)+3.44[4]
Details
A
Mass1.4[5] M☉
Radius1.49+0.04
−0.06[1] R☉
Luminosity3.581±0.17[1] L☉
Surface gravity (log g)4.11[6] cgs
Temperature6,514±118[1] K
Metallicity [Fe/H]0.08[5] dex
Rotational velocity (v sin i)34.9[7] km/s
Age900 Ma[4]
250+750
−50[5] Myr
Other designations
υ Aqr, 59 Aquarii, BD−21 6251, FK5 849, HD 213845, HIP 111449, HR 8592, SAO 191235[8]
Database references
SIMBADdata

Upsilon Aquarii, Latinized from υ Aquarii, is the Bayer designation for a binary star[9] system in the equatorial constellation of Aquarius. It is visible to the naked eye as a faint star with an apparent visual magnitude of 5.21.[2] Parallax measurements give a distance estimate of 74.8 light-years (22.9 parsecs) from Earth.[1] This is a high proper-motion star[8] that is drifting closer to the Sun with a radial velocity of –2.3 km/s.[1] It is part of the Hercules-Lyra association.[9]

The primary component is an F-type main sequence star with a stellar classification of F7 V.[3] It is less than a billion[4][5] years old and is spinning with a projected rotational velocity of 35 km/s.[7] The star has 1.4[5] times the mass of the Sun and 1.5[1] times the Sun's radius. It is radiating 3.6[1] times the Sun's luminosity from its photosphere at an effective temperature of 6,597 K,[6] giving it the yellow-white hue of an F-type star.[10]

The star displays an excess of near infrared radiation, suggesting it has a circumstellar disk of dusty debris.[11] This disk has a mean temperature of 75±17 K and is orbiting at an estimated radius of 84±41 AU.[12] A faint stellar companion was detected in 2007 at the Gemini Observatory, with a separation of 6.09″±0.03″ from the primary.[9] This is equivalent to a physical projected separation of 139 AU, which yields an estimated orbital period of ~1,330 years.[13] The debris disk is orbiting close to the dynamically unstable region of this system.[12]

  1. ^ a b c d e f g h i j k l m Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference clpl4_99 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference aaa418_989 was invoked but never defined (see the help page).
  5. ^ a b c d e Cite error: The named reference Vigan_et_al_2017 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference aj132_1_161 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference aaa493_3_1099 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference apj670_2_1367 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference csiro was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Ertel_et_al_2014 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Yelverton_et_al_2019 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Rodriguez_et_al_2015 was invoked but never defined (see the help page).