Analysis of Q-type Near-Earth Asteroid Spectra with Modified Gaussian Models

Abstract Using the Modified Gaussian Model (MGM) developed by Sunshine et al., we extract the mineralogical information from the reflection spectra of eight Q-type near-Earth asteroids, and obtain their surface composition of orthopyroxene and clinopyroxene. We further get a compositional proportion of each asteroid: the abundance of clinopyroxene is about 70% on the surfaces of the asteroids 5143, 7341, 66146, and 162058, and it is about 60% on the surfaces of the asteroids 1862, 4688, and 5660, but only 43% on the surface of the asteroid 3753. Then we analyse the reason for the apparently low abundance of clinopyroxene on the surface of the asteroid 3753. The level of metamorphism experienced by an asteroid increases with the decreasing distance from the Sun, so the asteroid 3753 is highly metamorphosed, and the abundance of clinopyroxene is low.