64 Angelina

64 Angelina is an asteroid from the central region of the asteroid belt, approximately 50 kilometers in diameter. It is an unusually bright form of E-type asteroid.

Discovery and naming

Angelina was discovered on March 4, 1861, by a prolific comet discoverer, E. W. Tempel, observing from Marseille, France. It was the first of his five asteroid discoveries.

The naming of Angelina caused some controversy. It was chosen by Benjamin Valz, director of the Marseille Observatory, in honour of the astronomical station of that name operated by Baron Franz Xaver von Zach on the mountains above the city. At the time, asteroids were supposed to receive names from classical mythology, and several astronomers protested against the choice. Tempel noted that if the second 'n' were removed, the complaints would be satisfied (referring to Angelia, a minor Greek deity). However, Valz's choice stayed.<ref>Template:Cite book</ref>

Physical characteristics

Angelina is a rare E-type asteroid; it is the second largest E-type after 44 Nysa, and has an exceptionally high albedo of 0.483.<ref>Template:Citation</ref><ref name=jpldata/> As of 1991, it is thought to have an average radius of about Template:Convert.<ref>Lionel Wilson and Klaus Keil – Explosive Eruptions on Asteroids: The Missing Basalts on the Aubrite Parent Body – Abstracts of the Lunar and Planetary Science Conference, volume 22, page 1515, (1991)</ref> Back when asteroids were generally assumed to have low albedos, Angelina was thought to be the largest of this class, but modern research has shown that its diameter is only a quarter of what was previously assumed, an error caused by its exceptional brightness. Traditional calculations had suggested that since Angelina has an absolute magnitude of 7.7 and an albedo of 0.15,<ref name=jpldata/> its diameter would have been around 100 km. However, a 2004 occultation showed a cross-sectional profile of only 48x53 km.<ref name="IOTA2004" /> Angelina was observed by Arecibo radar in January 2010.<ref name=Shepard2011 />

External links

• 2004 Angelina occultation (cross-sectional profile of 48x53 km)
• Template:AstDys
• Template:JPL small body