Asteroid distribution of spectral type with distance

Asteroid distribution of spectral type with distance

Fig. 12.8 . The color, or surface composition, of the asteroids is correlated with distance from the Sun. In order of increasing distance, there are the white E asteroids, the reddish S or silicate ones, the black C or carbonaceous ones, and the unusually red D asteroids. This systematic change has been attributed to a progressive decrease in temperature with distance from the Sun at the time the asteroids formed. Simple temperature differences within the primeval solar nebula cannot, however, explain the rare metallic M asteroids found in the middle of the asteroid belt; they are probably the cores of former, larger parent bodies.

Copyright 2010, Professor Kenneth R. Lang, Tufts University