HD 33519

HD 33519
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Mensa
Right ascension 05h 00m 13.23704s
Declination −78° 18 00.0987
Apparent magnitude (V) 6.28±0.01
Characteristics
Evolutionary stage red giant branch
Spectral type K5/M0 III
U−B color index +1.87
B−V color index +1.51
Astrometry
Radial velocity (Rv)−2.5±2.3 km/s
Proper motion (μ) RA: −17.781 mas/yr
Dec.: +1.497 mas/yr
Parallax (π)3.4534±0.0872 mas
Distance940 ± 20 ly
(290 ± 7 pc)
Absolute magnitude (MV)−0.88
Details
Mass4.34 M
Radius45.4 R
Luminosity465 L
Surface gravity (log g)1.45+0.02
0.03
 cgs
Temperature4,118±122 K
Metallicity [Fe/H]−0.01 dex
Rotational velocity (v sin i)<1 km/s
Other designations
19 G. Mensae, CD−78°190, CPD−78°165, HD 33519, HIP 23251, HR 1682, SAO 256153, WDS J05002-7818A
Database references
SIMBADdata

HD 33519, also known as HR 1682, is a probable spectroscopic binary located in the southern circumpolar constellation Mensa. It is one of the stars near the limit of naked eye visibility, having an apparent magnitude of 6.28. The system is relatively far at a distance of 940 light years but is approaching with a heliocentric radial velocity of −2.5 km/s. However, this value is poorly constrained.

The visible component has a stellar classification of K5/M0 III, indicating an evolved red giant with the characteristics of a K5 and M0 giant star. At present it has 4.34 times the mass of the Sun but has expanded to 45.4 times its girth. It shines with a luminosity of 465 L from its enlarged photosphere at an effective temperature of 4,118 K, giving it an orange-red hue when viewed in the night sky. HD 33519's metallicity, what astronomers dub as elements heavier than helium, is around solar level. Like most giants, it spins slowly, with its projected rotational velocity being lower than 1 km/s.

There is an 11th magnitude optical companion located 50.2 away along a position angle of 110°. It has no relation to the system, having a drastically different proper motion.