Explorers on the Moon (On a marché sur la Lune; literally: We walked on the Moon) is the seventeenth volume of The Adventures of Tintin, the comics series by Belgian cartoonist Hergé. The story was serialised weekly in Belgium's Tintin magazine from October 1952 to December 1953 before being published in a collected volume by Casterman in 1954. Completing a story arc begun in the preceding volume, Destination Moon (1953), the narrative tells of the young reporter Tintin, his dog Snowy, and friends Captain Haddock, Professor Calculus, and Thomson and Thompson who are aboard humanity's first crewed rocket mission to the Moon.
Developed in part through the suggestions of Hergé's friends Bernard Heuvelmans and Jacques Van Melkebeke, Explorers on the Moon was produced following Hergé's extensive research into the possibility of human space travel – a feat that had yet to be achieved – with the cartoonist seeking for the work to be as realistic as possible. Hergé continued The Adventures of Tintin with The Calculus Affair, while the series itself became a defining part of the Franco-Belgian comics tradition. Critics have held the illustrative detail of the book in high regard, but have expressed divided opinions of the story; some consider it to be among the most mature and emotionally resonant entries in the series, while others fault it for downplaying the humour seen in previous volumes in favour of the scientific focus of the narrative. The story was adapted for the 1957 Belvision animated series Hergé's Adventures of Tintin, the 1989 computer game Tintin on the Moon, the 1991 Ellipse/Nelvana animated series The Adventures of Tintin, and the 1992-3 BBC Radio 5 dramatisation of the Adventures.
The synopsis continues a plot begun in Destination Moon.
Professor Calculus, Tintin, Snowy, Captain Haddock, and Calculus's assistant Frank Wolff are aboard an atomic rocket-powered spacecraft leaving the Earth bound for the Moon. Soon after takeoff they discover that the detectives Thomson and Thompson have accidentally stowed away on board, putting a strain on the oxygen supply.