S71-36874 (10 June 1971) --- University of Texas geologist/professor William R. Muelhberger (left) talks with astronaut John W. Young, Apollo 16 commander, during an Apollo 16 geology field trip to Mono Crater, Calif. Astronaut Charles Duke, lunar module pilot, is seen at frame center, talking to geologist David Wones (second left). Astronaut Anthony England, Apollo 16 spacecraft communicator (CAPCOM), is at right. Photo credit: NASA