Geological Chronicle
Located in the Descartes Highlands at coordinates -8.8151, 15.4843, North Ray is the largest crater sampled directly by astronauts during the Apollo program. The crater measures 0.95 km in diameter and approximately 240 meters deep. Its inner slopes drop gently for the first 50 meters before steepening sharply toward a floor that remained out of view from the crater rim.
On April 21, 1972, Apollo 16 astronauts John Young and Charles Duke landed the Lunar Module Orion between North Ray and South Ray craters. Driving the Lunar Roving Vehicle approximately 4.4 kilometers north from their lander during EVA 3, they reached Station 11 on the southeastern rim of North Ray. There they examined House Rock, a boulder measuring 10 meters high by 20 meters long, and sampled a smaller adjacent fragment known as South Boulder or Outhouse Rock.
North Ray cuts into the Cayley Formation of Imbrian age, but the crater itself is much younger, of Copernican age, based on the presence of rays. Cosmic ray exposure analysis of noritic anorthosite sample 67955 established that the impact creating the crater occurred 50 million years ago. Radiometric dating of the rock itself yielded an age of 4.20 ± 0.07 billion years, preserving ancient crustal material exposed by the Copernican impact.