Apollo 16 astronaut Charles Duke didn't just leave footprints when he visited the lunar surface, he also left a photograph of his family 40 years ago.
On 23 April 1972, Duke and John Young embarked on a mission to explore the moon's Descartes Highlands in a Lunar Roving Vehicle.
Before setting up a Solar Wind Collector, Lunar Module pilot Duke left a photograph of himself with his wife and their two sons, Thomas and Charles, sitting on a bench. It remains there till this day, the Daily Mail reported.
The reverse of the photo is signed by Duke's family and bears the message: "This is the family of Astronaut Duke from Planet Earth. Landed on the Moon, April 1972."
Duke photographed the family picture with a Hasselblad camera as it rested on the dusty surface next to one of his boot prints.
The image was unearthed in the Project Apollo Image Archive, which serves as an online reference source and repository of digital images pertaining to the historic manned lunar landing programme.
He also left a commemorative medal issued by the United States Air Force, which was celebrating its 25th anniversary in 1972.
Apollo 16 was the tenth manned mission in the United States Apollo space programme, the fifth to land on the Moon and the first to land in the lunar highlands.
At the age of 36, Duke became the tenth and youngest human to walk on the Moon.