858 El Djezaïr is a stony

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 ...

from the

asteroid 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 ...

, about 24 kilometers in diameter. It was discovered on 26 May 1916, by French astronomer

Frédéric Sy Frédéric Sy (1861-1917) was a French astronomer and a discoverer of minor planets. He worked at the Paris Observatory from 1879 to 1887, and as the assistant astronomer at the Algiers Observatory, North Africa, from 1887 to 1918. While workin ...

at the

Algiers Observatory The Algiers Observatory was built in the late 19th century in the Algiers suburb of Bouzaréah, Algeria, North Africa. It participated in the Astrographic Catalogue project, taking the zone between -2 and +4 degrees to expose 1,260 plates betwe ...

in Algeria, North Africa, and given the provisional designation 1916 a. The asteroid orbits the Sun at a distance of 2.5–3.1 AU once every 4.71 years (1,722 days). The bright

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 ...

has a very high geometric albedo of 0.32. Its rotation period has been measured to take 22 hours and 20 minutes. Along with the asteroids

68 Leto 68 Leto is a large main belt asteroid that is orbiting the Sun. The asteroid was discovered by German astronomer Robert Luther on April 29, 1861, and is named after Leto, the mother of Apollo and Artemis in Greek mythology. It orbits at a dist ...

and 236 Honoria, it is a member of the Leto family, a small, well-defined group of asteroids, all with a semi-major axis of close to 2.8 AU. El Djezaïr is the French spelling of the Arabic name for Algiers, the capital of Algeria. It means "the islands". The asteroid was the first minor planet to receive a name that consists of more than one word. Its designation, 1916 a, is a superseded version of the modern two-letter code system of provisional designation, implemented just a few years later in 1925.

References

External links

Lightcurve plot of 858 El Djezair
Palmer Divide Observatory, B. D. Warner (2005)
Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * 000858 Discoveries by Frédéric Sy Named minor planets 000858 19160526 {{beltasteroid-stub