205 Martha

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 13 October 1879, in Pola and was named after Martha, a woman in the New Testament.

DiscoveredbyJohann Palisa

Discoverydate13 October 1879

MPCdesignation

(205) Martha

Pronunciation/ˈmɑːrθə/^[1]

Quick facts Discovery, Discovered by ...

205 Martha

Orbital diagram
Discovery
Discovered by	Johann Palisa
Discovery date	13 October 1879
Designations
MPC designation	(205) Martha
Pronunciation	/ˈmɑːrθə/[1]
Named after	Martha of Bethany
Alternative designations	A879 TB
Minor planet category	Main belt
Orbital characteristics[2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	136.51 yr (49860 d)
Aphelion	2.8758 AU (430.21 Gm)
Perihelion	2.6783 AU (400.67 Gm)
Semi-major axis	2.7771 AU (415.45 Gm)
Eccentricity	0.035571
Orbital period (sidereal)	4.63 yr (1690.3 d)
Average orbital speed	17.87 km/s
Mean anomaly	198.37°
Mean motion	0° 12m 46.692s / day
Inclination	10.696°
Longitude of ascending node	211.792°
Argument of perihelion	177.281°
Physical characteristics
Dimensions	80.58±1.4 km
Synodic rotation period	14.911 h (0.6213 d)
Geometric albedo	0.0553±0.002
Spectral type	C
Absolute magnitude (H)	9.23

Close

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.^[3]