Although both on the Moon and on Mars and Venus there are artificial objects made by man, which were left there by probes, vehicles or, in the lunar case, directly by astronauts, none of them was conceived as a work of art whose purpose was stay in them.
Except one, the fallen astronaut which can thus be considered as the only work of art designed to be installed outside our planet.
It is a small aluminum sculpture 8.5 centimeters high that wants to represent an astronaut in his space suit. It was made by the Belgian artist Paul Van Hoeydonck, who was commissioned by astronaut David Scott in 1970. The specifications included that the sculpture had to be light but robust and capable of withstanding the extreme temperatures of the Moon. He could not have any recognizable sex or race/ethnicity traits.
The objective was to create a commemorative monument for the deceased astronauts and cosmonauts of the space race, as well as a tribute to humanity’s desire to expand into space. On this point it seems that Scott and Van Hoeydonck disagree. The artist later stated that he did not know that the statue would be used as a memorial, but that he believed that it would represent all of Humanity.

Scott took the statuette with him on Apollo 15 without informing NASA, and on August 1, 1971, he placed the work in its current location on the Moon, along with an aluminum plate bearing the names of eight astronauts and six cosmonauts: Theodore Freeman, Charles Bassett, Elliott See, Gus Grissom, Roger Chaffee, Edward White, Vladimir Komarov, Edward Givens, Clifton Williams, Yuri Gagarin, Pavel Belyayev, Gueorgui Dobrovolski, Viktor Patsayev and Vladislav Volkov. All of them died between 1964 and 1971, some on space missions and others in plane or other accidents.
The chosen location was the Rima Hadley, a crack in the lunar surface to the west of Mons Hadley (4,600 meters high), and at the foot of the Apenninus Mountains in the northern hemisphere of the Moon. The crack has a length of 120 kilometers and a width of 2 kilometers, with a depth of 300 meters. Apollo 15 landed in its vicinity, moving the astronauts to the edge of the crack with the lunar rover.
Scott made the memorial public after the mission, in a press conference in which he also warned about the omission of the names of two other cosmonauts, Valentin Bondarenko and Grigori Nelyubov, of whom he was unaware due to the secrecy of the Soviet space program. Also missing is the name of Robert Henry Lawrence Jr., the first black astronaut, who died in an accident in 1967.
Van Hoeydonck later created a replica that is now kept at the National Air and Space Museum in the United States, and tried to market up to 950 copies, before NASA forbade it. Only 50 copies exist today, all of them in the possession of Van Hoeydonck.
Sources
The Sculpture on the Moon / Fallen Astronaut / Smithsonian National Air and Space Museum / Wikipedia