Psi Scorpii

ψ Scorpii

Observation data Epoch J2000      Equinox J2000
Constellation	Scorpius
Right ascension	Template:RA
Declination	Template:DEC
Apparent magnitude (V)	4.94
Characteristics
Spectral type	A1 V
U−B Template:Engvar	+0.11
B−V Template:Engvar	+0.09
Astrometry
Radial velocity (Rv)	−5.10 km/s
Proper motion (μ)	RA: −18.000 mas/yr Dec.: −36.188 mas/yr
Parallax (π)	20.1801±0.2617 mas
Distance	Template:Rnd ± Template:Rnd ly (Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)	+1.55
Details
Mass	Template:Val Template:Solar mass
Radius	Template:Val Template:Solar radius
Luminosity	18.6 Template:Solar luminosity
Surface gravity (log g)	Template:Val cgs
Temperature	Template:Val K
Rotational velocity (v sin i)	Template:Val km/s
Age	451 Myr
Metallicity [Fe/H]	{{{metal_fe2}}} dex
Other designations
Template:Odlist
Database references
SIMBAD	data

Psi Scorpii, which is Latinized from ψ Scorpii, is a star in the zodiac constellation of Scorpius. It is white in hue and has an apparent visual magnitude of 4.94, which is bright enough to be faintly visible to the naked eye. Based upon parallax measurements, it is located at a distance of around 162 light years from the Sun. Data collected during the Hipparcos mission suggests it is an astrometric binary, although nothing is known about the companion. The system is drifting closer to the Sun with a radial velocity of −5 km/s.

The visible component is an A-type main sequence star with a stellar classification of A1 V; a class of star that is still fusing hydrogen at its core. It has around 2.2 the mass and 2.08 times the radius of the Sun, and is shining with 18.6 times the Sun's luminosity. The effective temperature of the star's outer atmosphere is 8,650 K. Psi Scorpii is around 451 million years old and is spinning with a projected rotational velocity of 42.3 km/s.