Nu Hydri

Nu Hydri
Location of ν Hydri (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Hydrus
Right ascension 02h 50m 28.45915s[1]
Declination −75° 04′ 00.9969″[1]
Apparent magnitude (V) 4.76[2]
Characteristics
Spectral type K3III[3]
U−B color index +1.56[4]
B−V color index +1.33[4]
Astrometry
Radial velocity (Rv)+3.09±0.16[1] km/s
Proper motion (μ) RA: −33.392[1] mas/yr
Dec.: −27.286[1] mas/yr
Parallax (π)9.8538 ± 0.1433 mas[1]
Distance331 ± 5 ly
(101 ± 1 pc)
Absolute magnitude (MV)−0.33[2]
Details
Mass3.5[5] or 1.79[6] M☉
Radius21.23+3.23
−4.50[1] R☉
Luminosity183.8±3.2[1] L☉
Surface gravity (log g)3.30[7] cgs
Temperature4,612+584
−315[1] K
Metallicity [Fe/H]−1.52[7] dex
Rotation50 d[5]
Rotational velocity (v sin i)1.3[8] km/s
Age2.38[6] Gyr
Other designations
ν Hyi, CPD−75°204, FK5 2199, GC 3463, HD 18293, HIP 13244, HR 872, SAO 255929[9]
Database references
SIMBADdata

ν Hydri, Latinized as Nu Hydri, is a single[10] star in the southern circumpolar constellation of Hydrus. It is orange-hued and faintly visible to the naked eye with an apparent visual magnitude of 4.76.[2] This object is located approximately 331 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +3 km/s.[1] It is a member of the Ursa Major Moving Group of stars that share a common motion through space.[11]

This is an aging giant star with a stellar classification of K3III.[3] With the supply of hydrogen at its core exhausted, the star has expanded and cooled. At present it has 21[1] times the girth of the Sun. It is 2.4[6] billion years old with estimates of its mass ranging from 1.8[6] to 3.5[5] times the mass of the Sun. The star is radiating 184[1] times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,612 K.[1]

  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 XHIP 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 Cite error: The named reference Mallama2014 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Gondoin2005 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference luck2015 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Soubiran2016 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference deMedeiros2014 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Chupina2006 was invoked but never defined (see the help page).