Alfred M. Worden, who orbited the moon in the summer of 1971, taking sophisticated photographs of the lunar terrain while his fellow astronauts of the Apollo 15 mission roamed its surface in a newly developed four-wheel rover, died overnight at an assisted living center in Sugar Land, Texas, his family said on Wednesday. He was 88.

His son-in-law Bill Penczak said that Mr. Worden, who had lived in League City, Texas, apparently had a stroke.

Apollo 15 was NASA’s first moon mission devoted mainly to science. The flight of Apollo 11 in July 1969 had fulfilled President John F. Kennedy’s call for America to reach the moon by the end of the 1960s. But the three lunar landings that preceded Apollo 15 had yielded relatively modest insight into the moon’s origin and composition.

Major Worden, of the Air Force, spent three days in orbit operating a pair of cameras in his space capsule Endeavour.