the plaque on the Apollo 11 lunar module

https://grandoldpartisan.typepad.com/blog/2023/07/apollo-11-plaque.html

Grand Old Partisan highlights a pious moment during the Apollo 11 moon landing. On the lunar module was a plaque with images of Earth and an inscription and the President’s signature.

July 21st 1969, astronaut Neil Armstrong uncovered it and radioed:

"For those who haven't read the plaque, we'll read the plaque that's on the front landing gear of this LM. First there's two hemispheres, one showing each of the two hemispheres of the Earth. Underneath it says 'Here Men from the planet Earth first set foot upon the Moon, July 1969 A.D. We came in peace for all mankind.' It has the crew members' signatures and the signature of the President of the United States."

Richard Nixon had insisted on mentioning God, so NASA added A.D. to the date. A.D. is short for Anno Domini, or In The Year Of The Lord.