205 Martha

205 Martha

Discovery
Discovered by	Johann Palisa
Discovery date	October 13, 1879
Designations
Named after	Martha
Minor planet category	Main belt
Orbital characteristics
Epoch 30 January 2005 (JD 2453400.5)
Aphelion	2.878 AU
Perihelion	2.676 AU
Semi-major axis	2.777 AU
Eccentricity	0.036
Orbital period	1690.412 d (4.63 yr)
Average orbital speed	17.87 km/s
Mean anomaly	29.923°
Inclination	10.695°
Longitude of ascending node	212.069°
Argument of perihelion	171.423°
Physical characteristics
Dimensions	81.0 km
Rotation period	9.637 h
Albedo	0.054
Spectral type	C
Absolute magnitude (H)	9.23

205 Martha is a large main belt asteroid. It is a dark, primitive carbonaceous C-type asteroid. This object was discovered by Johann Palisa on October 13, 1879 in Pola and was named after Martha, a woman in the New Testament.

Efforts to determine the rotation period for this asteroid have produced wildly different results, in large part because the actual period is close to half of an Earth day. A study performed during 2013 showed that the light curve changed significantly during the observation period, adding to the difficulty. This study gave a synodic rotation period of 14.905 ± 0.001 h.^[1]

References

1. Hawkins, Scot; Ditteon, Richard (January 2014), "Asteroid Lightcurve Analysis at the Oakley Observatory - May 2007", Minor Planet Bulletin 41 (1): 47–49, Bibcode:2014MPBu...41...47P.

External links

• The Asteroid Orbital Elements Database
• Minor Planet Discovery Circumstances
• Asteroid Lightcurve Parameters
• Asteroid Albedo Compilation
• 205 Martha at the JPL Small-Body Database

• Discovery · Orbit diagram · Orbital elements · Physical parameters