C-type asteroid
A C-type asteroid is a dark, carbon-rich asteroid, linked to carbonaceous chondrite meteorites.
C-type asteroids are dark, reflecting only about 3 to 10 per cent of the sunlight that falls on them, and have fairly flat spectra. The C stands for carbonaceous. They are the commonest type in the outer part of the main asteroid belt and include large bodies such as Hygiea.
Their spectra are similar to those of carbonaceous chondrites, and many show signs of water-bearing minerals. Two closely related dark types, B-type and Cb-type, describe Bennu and Ryugu, whose returned samples proved to be rich in clays, carbonates and organic compounds, much like CI chondrites.
C-type asteroids are important because they hold some of the most primitive material in the Solar System, including water and carbon compounds. Many scientists think asteroids like them helped deliver water and the ingredients for life to the early Earth. Their weak, crumbly material also explains why carbonaceous meteorites are rarer than you might expect: much of it breaks up in the atmosphere.
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Level: Explorer Ages 10 and up