Want to stay on top of all the space news? Follow @universetoday on TwitterThe asteroid 511 Davida, also known as 1903 LU, was discovered in 1903 by R.S. Dugan. It is a C type asteroid with a mass of 6.64 x 1019kg and is 270–310 km in diameter. It is thought to rotate every 5.131 hours. This asteroid accounts for approximately 1.5% of the total mass of the main asteroid belt. Scientists consider it to be one of the ten most massive asteroids with most mass estimates placing it as the fifth or sixth most massive.
A C type asteroid is a carbonaeous(carbon rich) asteroid. C type asteroids are the most common variety of asteroid and account for about 75% of all known asteroids. This type of asteroid is most dominate at the outer edges of the main belt, particularly beyond 2.7 AU. C-type asteroids are very dark (albedos typically in the 0.03 to 0.10 range)and can be hard to detect, so the percentage may be even higher. D type asteroids are the only class that is darker. C type asteroids display a very similar spectra to carbonaeous chondrite meteorites. That means that their chemical composition is approximately the same as the Sun and the primitive solar nebula including hydrated minerals, but missing the volatiles.
511 Davida is one of the few main belt asteroids whose shape has been determined by ground-based visual observation. From 2002 to 2007, astronomers at the Keck Observatory used the Keck II telescope, which is fitted with adaptive optics, to photograph the asteroid. The observational data included images of two promontories and one flattened area that may be 15 km deeper than the surrounding surface features. The flattened area appears to be a 150 km crater that would be considered a global event. Research has shown that an impact of this size on the surface of an asteroid as relatively large as Davida would not have caused a major disruption(breaking apart or change in orbit) of the asteroid.
Asteroid Davida interests scientists on several levels. It offers them the opportunity to visually observe debris from the early solar nebula as well as to study the implications of an impact on a celestial body smaller than a planet.
Answers.com has a little information on the asteroid Davida. Here on Universe Today we have a great article on the adaptive equipment that the Keck Observatory used to see 511 Davida. Just for fun here is a link to an episode on Astronomy Cast about the search for E.T.