HD 189080

HD 189080, also known as HR 7621 or rarely 74 G. Telescopii, is a solitary orange-hued star located in the southern constellation Telescopium. It has an apparent magnitude of 6.18,^[2] placing it near the limit for naked eye visibility. Gaia DR3 parallax measurements place it at a distance of 357 light years ^[1] and it is currently receding rapidly with a heliocentric radial velocity of 66.9 km/s.^[6] At its current distance, HD 189080's brightness is diminished by 0.17 magnitudes due to extinction from interstellar dust.^[14] It has an absolute magnitude of +1.1.^[7]

HD 189080

Location of HD 189080 (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Telescopium
Right ascension	20h 00m 25.32793s[1]
Declination	−49° 21′ 03.4019″[1]
Apparent magnitude (V)	6.18±0.01[2]
Characteristics
Evolutionary stage	red giant branch[3]
Spectral type	K0 III[4]
U−B color index	+0.92[5]
B−V color index	+1.06[5]
Astrometry
Radial velocity (Rv)	66.9±0.4[6] km/s
Proper motion (μ)	RA: −77.932 mas/yr[1] Dec.: −2.298 mas/yr[1]
Parallax (π)	9.1277±0.0321 mas[1]
Distance	357 ± 1 ly (109.6 ± 0.4 pc)
Absolute magnitude (MV)	+1.10[7]
Details
Mass	1.19+0.16 −0.29[8] M☉
Radius	9.9±0.5[9] R☉
Luminosity	43.6±1.0[10] L☉
Surface gravity (log g)	2.46+0.09 −0.10[8] cgs
Temperature	4,742±49[10] K
Metallicity [Fe/H]	−0.11±0.03[10] dex
Rotational velocity (v sin i)	<1[11] km/s
Age	4.83+2.53 −3.22[8] Gyr
Other designations
74 G. Telescopii[12], CD−49°12949, CPD−49°11118, FK5 3595, GC 27678, HD 189080, HIP 98482, HR 7621, SAO 229973[13]
Database references
SIMBAD	data

This is an evolved red giant with a stellar classification of K0 III.^[4] It is currently on the red giant branch,^[3] fusing a hydrogen shell around an inert helium core. It has 119% the mass of the Sun, but at the age of 4.83 billion years^[8] it has expanded to 9.9 times the radius of the Sun.^[9] It radiates 43.6 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,742 K.^[10] HD 189080 is slightly metal deficient with [Fe/H] = −0.11^[10] and spins too slowly to be measured accurately.^[11]