Urda (

minor planet designation A formal minor-planet designation is, in its final form, a number–name combination given to a minor planet (asteroid, centaur, trans-Neptunian object and dwarf planet but not comet). Such designation always features a leading number (catalog or ...

: 167 Urda) is a

main-belt The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...

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 university teacher and astronomer at the Litchfield Observatory of Hamilton College, New York, and a pioneer in the study and visual discovery of ...

on August 28, 1876, in Clinton, New York, and named after Urd, one of the

Norns The Norns ( non, norn , plural: ) are deities in Norse mythology responsible for shaping the course of human destinies.'' Nordisk familjebok'' (1907) In the ''Völuspá'', the three primary Norns Urðr (Wyrd), Verðandi, and Skuld draw wate ...

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, and into the Nordic folklore of the modern period ...

. 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 Gel ...

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

Colorado Springs, Colorado Colorado Springs is a home rule municipality in, and the county seat of, El Paso County, Colorado, United States. It is the largest city in El Paso County, with a population of 478,961 at the 2020 United States Census, a 15.02% increase since ...

, during 2007–8 gave a

light curve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

with a period of 13.06133 ± 0.00002 hours. This

S-type asteroid S-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 of this type, making it the second ...

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 le ...

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 ...

. 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 ...

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