Psi Scorpii (HIP 79375)

Psi Scorpii is a white main-sequence star in the constellation Scorpius. At 144 light years away, it shines at an apparent visual magnitude of 4.93. It is moving through the Galaxy at a speed of 10.9 km/s relative to the Sun.

Sky position: RA 16h 12.0m, Dec -10° 3.8'

Common designations: Psi Scorpii, 15 Scorpii, HR 6031, HD 145570, HIP 79375, Gaia DR3 4344947181887184000

Psi Scorpii has the spectral type A1V. A-type stars are white stars with surface temperatures of roughly 7,500 to 10,000 K. Their spectra are dominated by strong hydrogen lines, and many of them rotate rapidly. Its luminosity class V means it is a main-sequence (dwarf) star, still fusing hydrogen into helium in its core like the Sun.

How to find Psi Scorpii in the sky

Psi Scorpii lies in Scorpius. With a declination of -10° 3.8', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 80° N. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around June, which makes the weeks around that month the best time to observe it.

Tabulated data for Psi Scorpii

Astrometry and spectroscopy

Right Ascension (J2000)	242.99997135° (16h 12.0m)
Declination (J2000)	-10.06414171° (-10° 3.8')
Galactic Longitude	2.54076711°
Galactic Latitude	28.81215211°
Proper motion RA	-1.48 mas/yr
Proper motion Dec	-31.35 mas/yr
Parallax	22.64 ± 0.49 mas
Spectral Type	A1V
Radial Velocity	-8.65 km/s

Photometry

Band	Magnitude	Abs. Mag.
B	5.03	1.80
V	4.93	1.70
J	4.96	1.73
H	4.89	1.66
K	4.63	1.41

Colour index B-V: +0.10

Derivations

Heliocentric distance: 44.17 pc (144 light years) (2.2% margin of error)
Absolute visual magnitude: 1.70
Transverse velocity: 6.6 km/s
Space velocity relative to the Sun: 10.9 km/s
Galactic position (X, Y, Z): 38.7 pc, 1.7 pc, 21.3 pc
Galactic velocity (U, V, W): -5.5 km/s, -5.6 km/s, -7.6 km/s

Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.