73 Leonis (HIP 55016)

73 Leonis is an orange giant star in the constellation Leo. At 463 light years away, it shines at an apparent visual magnitude of 5.32. It is moving through the Galaxy at a speed of 17.1 km/s relative to the Sun.

Sky position: RA 11h 15.9m, Dec +13° 18.5'

Common designations: 73 Leonis, n Leonis, HR 4365, HD 97907, HIP 55016, Gaia DR3 3965092440205592064

73 Leonis has the spectral type K2III. K-type stars are orange stars with surface temperatures of about 3,900 to 5,300 K. Their spectra are rich in neutral metal lines and, in the cooler examples, molecular bands. Its luminosity class III marks it as a giant: an evolved star that has left the main sequence and swollen to many times its original size.

How to find 73 Leonis in the sky

73 Leonis lies in Leo. With a declination of +13° 18.5', it is visible from the entire Northern Hemisphere and from the Southern Hemisphere down to about latitude 77° S. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around April, which makes the weeks around that month the best time to observe it.

Tabulated data for 73 Leonis

Astrometry and spectroscopy

Right Ascension (J2000)	168.96616713° (11h 15.9m)
Declination (J2000)	13.30756527° (+13° 18.5')
Galactic Longitude	239.93447007°
Galactic Latitude	63.74384378°
Proper motion RA	7.89 mas/yr
Proper motion Dec	-10.52 mas/yr
Parallax	7.04 ± 0.20 mas
Spectral Type	K2III
Radial Velocity	14.64 km/s

Photometry

Band	Magnitude	Abs. Mag.
U	7.61	1.85
B	6.52	0.76
V	5.32	-0.44
J	3.25	-2.51
H	2.66	-3.10
K	2.48	-3.28

Colour index B-V: +1.20

Derivations

Heliocentric distance: 141.98 pc (463 light years) (2.8% margin of error)
Absolute visual magnitude: -0.44
Transverse velocity: 8.9 km/s
Space velocity relative to the Sun: 17.1 km/s
Galactic position (X, Y, Z): -31.5 pc, -54.4 pc, 127.3 pc
Galactic velocity (U, V, W): 4.5 km/s, -9.9 km/s, 13.2 km/s

Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.