M-class asteroidA relatively bright and reflective asteroid, made mainly of metallic iron and nickel (the "M" is for "metal"), typically found in the middle of the main asteroid belt. M-class asteroids are slightly reddish and have featureless reflectance spectra over the range 0.3 to 1.1 microns. They are distinguished from the spectrally similar E-class asteroids and P-class asteroids by their moderate albedo of 0.10 to 0.18. The largest known example is the 248-km-wide (16) Psyche. Related category ASTEROIDS AND OTHER MINOR PLANETS: TYPES AND GROUPSAlso on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History |