205 Martha is a large

main belt The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids ...

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

. It is a dark, primitive

carbonaceous Carbonaceous refers to something relating to, containing, or composed of carbon. It is a descriptor used for the attribute of any substance rich in carbon. Particularly, ''carbonaceous hydrocarbons'' are very unsaturated, high- molecular-weight h ...

C-type asteroid C-type (carbonaceous ) asteroids are the most common variety, forming around 75% of known asteroids. They are volatile-rich and distinguished by a very low albedo because their composition includes a large amount of carbon, in addition to rocks ...

. This object was discovered by

Johann Palisa Johann Palisa (6 December 1848 – 2 May 1925) was an Austrian astronomer, born in Troppau, Austrian Silesia, now Czech Republic. He was a prolific discoverer of asteroids, discovering 122 in all, from 136 Austria in 1874 to 1073 G ...

on 13 October 1879, in Pola and was named after

Martha Martha (Aramaic language, Aramaic: מָרְתָא‎) is a Bible, biblical figure described in the Gospels of Gospel of Luke, Luke and Gospel of John, John. Together with her siblings Lazarus of Bethany, Lazarus and Mary of Bethany, she is descr ...

, a woman in the

New Testament The New Testament (NT) is the second division of the Christian biblical canon. It discusses the teachings and person of Jesus in Christianity, Jesus, as well as events relating to Christianity in the 1st century, first-century Christianit ...

. 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 In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...

changed significantly during the observation period, adding to the difficulty. This study gave a synodic

rotation period In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the '' sidereal rotation period'' (or ''sidereal day''), i.e., the time that the objec ...

of 14.905 ± 0.001 h.

References

External links

Lightcurve plot of 205 Martha
Palmer Divide Observatory, B. D. Warner (2010)
Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * 000205 Discoveries by Johann Palisa Named minor planets 000205 000205 18791013 {{C-beltasteroid-stub