A-type asteroid

A-type asteroids are fairly uncommon closer asteroids that have a strong, broad 1 µm olivine feature and a very reddish spectrum shortwards of 0.7 µm. They are thought to come from the completely differentiated mantle of an asteroid.

A-type asteroids are so rare that as of 2005 only 17 had been found.

 Other websites 
 A technical report on A-Type Asteroids

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