HIP 57274

HIP 57274
Observation data
Epoch J2000      Equinox J2000
Constellation Ursa Major
Right ascension 11h 44m 40.9643s[1]
Declination +30° 57′ 33.4509″[1]
Apparent magnitude (V) 8.96[2]
Characteristics
Spectral type K5 V[2]
U−B color index +1.06[3]
B−V color index +1.111±0.016[4]
Astrometry
Radial velocity (Rv)+29.76±0.35[1] km/s
Proper motion (μ) RA: −27.069±0.081[1] mas/yr
Dec.: −381.708±0.079[1] mas/yr
Parallax (π)38.6381 ± 0.0499 mas[1]
Distance84.4 ± 0.1 ly
(25.88 ± 0.03 pc)
Absolute magnitude (MV)6.89[2]
Details[2]
Mass0.73±0.05 M
Radius0.68±0.03 R
Luminosity0.19±0.01 L
Surface gravity (log g)4.71±0.1 cgs
Temperature4,640±100 K
Metallicity [Fe/H]+0.09±0.05 dex
Rotation45 d
Rotational velocity (v sin i)0.5±0.5 km/s
Age7.87±5 Gyr
Other designations
BD+31° 2290, Gaia DR2 4021079911593673600, GJ 439, HIP 57274, SAO 62684, LTT 13227, 2MASS J11444095+3057339[5]
Database references
SIMBADdata
ARICNSdata

HIP 57274 is a star in the northern circumpolar constellation of Ursa Major with a system of three planets.[2] It is invisible to the naked eye, having an apparent visual magnitude of 8.96.[2] The distance to this system is 84.4 light years based on stellar parallax, and it is drifting further away with a radial velocity of +30 km/s.[1] The star has a relatively high rate of proper motion, traversing the celestial sphere at the rate of 0.382 arcsecond/year.[6]

This is an ordinary K-type main-sequence star with a stellar classification of K5V.[2] It appears to be older than the Sun with an age of roughly eight billion years and is spinning slowly with a projected rotational velocity of under 1 km/s. The star has 73% of the mass of the Sun and 68% of the Sun's radius. The abundance of elements heavier than helium is about the same or slightly higher than in the Sun. The star is radiating just 19% of the luminosity of the Sun from its photosphere at an effective temperature of 4,640 K.

  1. ^ a b c d e f g 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 Fischer2012 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference EgUBV was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Simbad was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Lepine2005 was invoked but never defined (see the help page).