13 Trianguli

13 Trianguli is the Flamsteed designation for a star in the northern constellation of Triangulum. It has an apparent visual magnitude of 5.89,^[2] so according to the Bortle scale it is faintly visible from dark suburban skies. The star is located at a distance of 103 light years from the Sun based on parallax measurements,^[1] and is drifting further away with a radial velocity of +41 km/s.^[4] It made a close approach to the Sun some 665,000 years ago at an estimated separation of 34.3 light-years.^[2]

13 Trianguli

Location of 13 Trianguli (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Triangulum
Right ascension	02h 28m 48.49449s[1]
Declination	+29° 55′ 54.3286″[1]
Apparent magnitude (V)	5.89[2]
Characteristics
Spectral type	G0 V[2]
U−B color index	+0.01[3]
B−V color index	+0.591±0.014[2]
Astrometry
Radial velocity (Rv)	+40.8[4] km/s
Proper motion (μ)	RA: –66.071[1] mas/yr Dec.: +71.499[1] mas/yr
Parallax (π)	31.7031±0.1014 mas[1]
Distance	102.9 ± 0.3 ly (31.5 ± 0.1 pc)
Absolute magnitude (MV)	3.45[5]
Details
Mass	1.10±0.03[5] M☉
Radius	1.86±0.03[1] R☉
Luminosity	3.72[5] L☉
Temperature	5,846[5] K
Metallicity [Fe/H]	−0.24[6] dex
Rotational velocity (v sin i)	3[7] km/s
Age	6.45[5] Gyr
Other designations
13 Tri, BD+29 423, GJ 99.1, HD 15335, HIP 11548, HR 720, SAO 75391[3]
Database references
SIMBAD	data

A stellar classification of G0 V^[2] indicates this is a main sequence star that is generating energy by fusing hydrogen into helium at its core. It has about 110% of the Sun's mass, 186% of the Sun's radius, and shines with 3.72 times the luminosity of the Sun. The stellar atmosphere has an effective temperature of 5,846 K,^[5] giving it the yellow hue of a G-type star.^[8] It appears to be older than the Sun, with an estimated age of 6.45 billion years.^[5]

In 1994, an astrometric companion was reported at an angular separation of 0.020″. However, follow-up observations reported in 2005 not only failed to recover this object but also returned a null result on a search for planetary companions.^[9] The star has been examined for an infrared excess that could indicate the presence of an orbiting debris disk, but no such excess was found.^[6]