C-type asteroid

C-type or carbonaceous asteroids are the most abundant type of asteroid in the solar system. About 75% of all asteroids are C-type.

Characteristics and composition
C-type asteroids are among the darkest objects in the solar system, having albedos that vary from 0.03 to 0.09. They have a chemical composition similar to that of the Sun but lacking molecular hydrogen, helium, and other volatile elements. Some have stated that their composition is like that of carbonaceous chondrite meteorites. C-type asteroids predominate in the outer reaches of the asteroid belt.

Examples
The largest known C-type asteroid is Hygiea. Ceres would still be a C-type asteroid, were it not now classified as a dwarf planet. The asteroid Mathilde is another example of a C-type asteroid.

Observation and Exploration
C-type asteroids are too dim to view without a telescope.

The Near Earth Asteroid Rendezvous mission made rendezvous with and photographed the asteroid Mathilde in June of 1997 en route to its rendezvous with the asteroid Eros.

Related link

 * C-type asteroid by Wikipedia

Astéroïdes C-type Asteroides tipo-C