Which American astronaut was believed to have written their daughter's initials on the moon?

Eugene Andrew Cernan (March 14, 1934 – January 16, 2017) was an American astronaut, naval aviator, electrical engineer, aeronautical engineer, and fighter pilot. He is known significantly for being the eleventh man to walk on the Moon succeeding Charles Duke during the Apollo 17 mission. As he re-entered the Apollo Lunar Module after Harrison Schmitt on their third and final lunar trip in 1973, he was the last man to walk on the Moon as of 2021.

During his career, Cernan has traveled into space three times and to the Moon twice: as pilot of Gemini 9A in June 1966, as lunar module pilot of Apollo 10 in May 1969, and as commander of Apollo 17 in December 1972, the final Apollo lunar landing. Cernan was also a backup crew member of the Gemini 12, Apollo 7 and Apollo 14 space missions.

During the Apollo 17 mission, the final Apollo lunar landing, Cernan dropped to one knee and traced his daughter's initials, “TDC,” in the lunar dust before climbing the ladder of the lunar module the final time.