49 Orionis (HIP 26563)

49 Orionis is a white main-sequence star in the constellation Orion. At 142 light years away, it shines at an apparent visual magnitude of 4.80. It is moving through the Galaxy at a speed of 15.4 km/s relative to the Sun.

Sky position: RA 5h 38.9m, Dec -7° 12.8'

Common designations: 49 Orionis, d Orionis, HR 1937, HD 37507, GJ 9187, HIP 26563, Gaia DR3 3016083407149428096

49 Orionis has the spectral type A4Vn. 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 49 Orionis in the sky

49 Orionis lies in Orion. With a declination of -7° 12.8', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 83° N. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around January, which makes the weeks around that month the best time to observe it.

Tabulated data for 49 Orionis

Astrometry and spectroscopy

Right Ascension (J2000)	84.72117994° (5h 38.9m)
Declination (J2000)	-7.21282977° (-7° 12.8')
Galactic Longitude	211.16479104°
Galactic Latitude	-19.39764835°
Proper motion RA	-15.40 mas/yr
Proper motion Dec	-49.30 mas/yr
Parallax	22.96 ± 0.11 mas
Spectral Type	A4Vn
Radial Velocity	-11.07 km/s

Photometry

Band	Magnitude	Abs. Mag.
U	5.04	1.84
B	4.93	1.73
V	4.80	1.60
R	4.65	1.45
I	4.59	1.39
J	4.53	1.33
H	4.54	1.35
K	4.42	1.22

Colour index B-V: +0.13

Derivations

Heliocentric distance: 43.56 pc (142 light years) (0.5% margin of error)
Absolute visual magnitude: 1.60
Transverse velocity: 10.7 km/s
Space velocity relative to the Sun: 15.4 km/s
Galactic position (X, Y, Z): -35.2 pc, -21.3 pc, -14.5 pc
Galactic velocity (U, V, W): 15.0 km/s, 0.1 km/s, -3.3 km/s

Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.