167 Urda is a

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 that was discovered by German-American astronomer

Christian Heinrich Friedrich Peters Christian Heinrich Friedrich Peters (September 19, 1813 – July 18, 1890) was a German–American astronomer and professor at Hamilton College, New York, and a pioneer in the study and visual discovery of asteroids. His name is often given as ...

on August 28, 1876, in

Clinton, New York Clinton, New York may refer to: *Clinton County, New York *Clinton, Clinton County, New York *Clinton, Dutchess County, New York *Clinton, Oneida County, New York * Clinton, Manhattan, or Hell's Kitchen, a neighborhood in New York City *East Greenb ...

, and named after Urd, one of the

Norns The Norns ( , plural: ) are a group of deities in Norse mythology responsible for shaping the course of human destinies.''Nordisk familjebok'' (1907) The Norns are often represented as three goddesses known as Urd ( Urðr), Verðandi, and S ...

Norse mythology Norse, Nordic, or Scandinavian mythology, is the body of myths belonging to the North Germanic peoples, stemming from Old Norse religion and continuing after the Christianization of Scandinavia as the Nordic folklore of the modern period. The ...

. In 1905, Austrian astronomer

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 ...

showed that the asteroid varied in brightness. Photometric observations of this asteroid at the Palmer Divide Observatory in

Colorado Springs, Colorado Colorado Springs is the most populous city in El Paso County, Colorado, United States, and its county seat. The city had a population of 478,961 at the 2020 United States census, 2020 census, a 15.02% increase since 2010 United States Census, 2 ...

, during 2007–8 gave a

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 ...

with a period of 13.06133 ± 0.00002 hours. This

S-type asteroid S-type (stony-type or silicaceous-type) asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are ...

is a member of the

Koronis family ] The Koronis or Koronian family (), also known as the Lacrimosa family, is a very large asteroid family of S-type asteroid, stony asteroids, located in the Kirkwood gap, outer region of the asteroid belt. They are thought to have been formed at l ...

of asteroids that share similar

orbital elements Orbital elements are the parameters required to uniquely identify a specific orbit. In celestial mechanics these elements are considered in two-body systems using a Kepler orbit. There are many different ways to mathematically describe the same o ...

. In 2002, a diameter estimate of 37.93 ± 3.17 km was obtained from the

Midcourse Space Experiment The Midcourse Space Experiment (MSX) is a Ballistic Missile Defense Organization (BMDO) satellite experiment (unmanned space mission) to map bright infrared sources in space. MSX offered the first system demonstration of technology in space t ...

observations, with an albedo of 0.2523 ± 0.0448. A stellar

occultation An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks f ...

by Urda was observed from Japan on July 23, 2001.

References

External links

Lightcurve plot of 167 Urda
Palmer Divide Observatory, '' B. D. Warner'' (2007)
Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * Koronis asteroids Urda Urda S-type asteroids (Tholen) Sk-type asteroids (SMASS) 18760828 Objects observed by stellar occultation {{S-beltasteroid-stub