Lunar Surface (IMAGE) Geological Society of America Caption The surface of the Moon is covered in powdery gray dust that caused unforeseen problems for NASA astronauts. Apollo 17 astronaut Harrison "Jack" Schmitt took this picture of Eugene Cernan during their third and last walk on the lunar surface in December of 1972. Credit NASA Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.