154 BERTHA

'154 Bertha'

Orbital characteristics [ftp://ftp.lowell.edu/pub/elgb/astorb.html 1]
Orbit type	Main belt
Semimajor axis	3.189 AU
Perihelion distance	2.920 AU
Aphelion distance	3.459 AU
Orbital period	5.70 years
Inclination	21.03°
Eccentricity	0.084
Physical characteristics [ftp://ftp.lowell.edu/pub/elgb/astorb.html 1]
Diameter	184.93 km
Rotation period	12 hours
Spectral class	C
Abs. magnitude	7.58
Albedo 4	0.048
History 2
Discoverer	P. M. Henry, 1875

'154 Bertha' is a very dark and very large outer Main belt asteroid.
It was discovered by brothers Paul Henry and Prosper Henry on November 4, 1875, but the credit from the discovery was given to Prosper. It is probably named after Berthe Martin-Flammarion, sister of the astronomer Camille Flammarion.