HD 231701

HD 231701 / Uruk
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Sagitta
Right ascension 19h 32m 04.1610s[1]
Declination +16° 28′ 27.4411″[1]
Apparent magnitude (V) 8.97[2]
Characteristics
Evolutionary stage main sequence
Spectral type F8 V[2]
B−V color index 0.539±0.015[2]
Astrometry
Radial velocity (Rv)−63.36±0.19[1] km/s
Proper motion (μ) RA: 63.363±0.053[1] mas/yr
Dec.: 15.650±0.052[1] mas/yr
Parallax (π)9.1560 ± 0.0393 mas[1]
Distance356 ± 2 ly
(109.2 ± 0.5 pc)
Absolute magnitude (MV)3.64[2]
Details
Mass1.23±0.10[3] M☉
Radius1.45+0.01
−0.04[1] R☉
Luminosity2.572±0.016[1] L☉
Surface gravity (log g)4.37±0.03[4] cgs
Temperature6,081+72
−24[1] K
Metallicity [Fe/H]0.04±0.02[5] dex
Rotational velocity (v sin i)4.26[4] km/s
Age3.22±1.99[3] or 4.5[6] Gyr
Other designations
BD+16° 3883, HD 231701, HIP 96078, SAO 104946[7]
Database references
SIMBADdata

HD 231701 is a yellow-white hued star in the northern constellation of Sagitta, near the southern constellation border with Aquila. With an apparent visual magnitude of 8.97,[2] it is too dim to be viewed with the naked eye, but can be seen with powerful binoculars or a small telescope. Parallax measurements provide a distance estimate of approximately 356 light years from the Sun, but it is drifting closer with a radial velocity of −63 km/s.[1] It is predicted to come as close as 189.5 light-years in 1.345 million years.[2]

HD 231701 is named Uruk. The name was selected in the NameExoWorlds campaign by Iraq, during the 100th anniversary of the IAU. Uruk was an ancient city of the Sumer and Babylonian civilizations in Mesopotamia.[8][9]

This object is an ordinary F-type main-sequence star with a stellar classification of F8 V.[2] It is around three[3] to 4.5 billion years old and may be evolving onto the subgiant branch.[6] It is spinning with a projected rotational velocity of 4 km/s[4] and has low chromospheric activity.[6] HD 231701 has 1.2[3] times the mass of the Sun and 1.45[1] times the Sun's radius. It is radiating 2.6 times the luminosity of the Sun from its photosphere at an effective temperature of 6,081 K.[1]

In 2007, the N2K Consortium used the radial velocity technique to discover a Jupiter-like planet orbiting at a distance of 0.57 AU from the star with a period of 141.6 days.[6]

The HD 231701 planetary system[10]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b / Babylonia ≥1.13±0.25 MJ 0.567±0.053 141.63±0.067 0.13±0.032 — —
  1. ^ a b c d e f g h i j k l Cite error: The named reference Gaia DR2 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 c d Cite error: The named reference Earle2017 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference DelgadoMena2015 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Santos2013 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Fischer2007 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ "Approved names". NameExoworlds. Retrieved 2020-01-02.
  9. ^ "International Astronomical Union | IAU". www.iau.org. Retrieved 2020-01-02.
  10. ^ Cite error: The named reference Ment2018 was invoked but never defined (see the help page).