Geological Chronicle
South Ray crater sits in the Descartes Highlands of the Moon, an area photographed from the lunar surface by Apollo 16 astronauts John Young and Charles Duke. The Lunar Module Orion landed between North Ray and South Ray craters on April 21, 1972, placing the crew within reach of both features yet separated from South Ray by nearly four kilometers.
On their second excursion, Young and Duke drove south toward South Ray, stopping at Station 4 near Cinco crater, about 3.9 km south of the landing site. From there, Duke photographed the crater using a 500-mm lens. The ejecta of South Ray was so heavily covered with large boulders that the crew judged it would have been difficult or impossible to drive the Lunar Roving Vehicle across it.
South Ray measures approximately 700 m in diameter and 120 m deep, with a bright system of rays of ejecta extending outward across the highlands. It cuts into the Cayley Formation, a deposit of Imbrian age, though the crater itself is considerably younger, dating to the Copernican period. The IAU formally adopted the name South Ray in 1973.