148 Gallia

148 Gallia

Discovery[1]
Discovered by	Paul Henry and Prosper Henry
Discovery date	August 7, 1875
Designations
Named after	Gaul
Minor planet category	Main belt
Orbital characteristics[2]
Epoch December 31, 2006 (JD 2454100.5)
Aphelion	491.906 Gm (3.288 AU)
Perihelion	336.871 Gm (2.252 AU)
Semi-major axis	414.388 Gm (2.770 AU)
Eccentricity	0.187
Orbital period	1683.920 d (4.61 a)
Average orbital speed	17.74 km/s
Mean anomaly	123.742°
Inclination	25.299°
Longitude of ascending node	145.192°
Argument of perihelion	252.131°
Physical characteristics
Dimensions	83.45 ± 5.07 km
Mass	(4.89 ± 1.67) × 1018 kg
Mean density	16.06 ± 6.22 g/cm3
Equatorial surface gravity	0.0273 m/s²
Equatorial escape velocity	0.0517 km/s
Rotation period	20.664 h
Geometric albedo	0.10
Temperature	~167 K
Spectral type	GU (Tholen)
Absolute magnitude (H)	7.72

148 Gallia (as Greek Γαλλία) is a large main-belt asteroid that is named after the Latin name for France: Gaul. Gallia was discovered by the French brothers Paul Henry and Prosper Henry on August 7, 1875, but the credit for this discovery was given to Prosper. Based upon its spectrum, this is a GU-type asteroid in the Tholen classification taxonomy, while Bus and Binzel (2002) categorize it as an S-type asteroid.

Photometric observations of this asteroid at the European Southern Observatory in 1977–78 gave a light curve with a period of 0.86098 ± 0.00030 days (20.6635 ± 0.0072 h) and a brightness variation of 0.32 in magnitude. A 2007 study at the Palmer Divide Observatory in Colorado Springs, Colorado yielded a period of 20.666 ± 0.002 h with a magnitude variation of 0.21.

This object is the namesake of a family of 22–113 asteroids that share similar spectral properties and orbital elements. Hence they may have arisen from the same collisional event. All members have a relatively high orbital inclination.