Tractus Catena pit-chains

Tractus Catena from the nadir and colour channels, combined to form a natural colour view of the region. The pit-chains have analogues on both Earth and the Moon, with the Mexican Cenotes being one of the most famous and dramatic examples on Earth. On the Moon, Hadley Rille, visited by Apollo 15 in 1971, is believed to have formed from the collapse of a lava tube billions of years ago.