NASA astronaut Buzz Aldrin photographed the indentations left by his spacesuit boot on the dusty lunar surface. That mark inspired the Mint's design, which takes a little artistic license by filling in the shadows.
The obverse artwork comes from Maine sculptor Gary Cooper, who included an inscription reading Mercury, Gemini and Apollo to mark the NASA programs that led up to the first crewed moon landing.
The reverse design comes from Mint sculptor and engraver Phebe Hemphill, who created a moon scene showing Neil Armstrong, the US flag, and the lunar lander. It's based on a photo taken by Armstrong of Aldrin with a reflection of that scene in Aldrin's helmet visor.
One unusual feature is that the coins will be curved so as to mirror the curve of Aldrin's visor. The Mint previously released a curved baseball glove coin in 2014.
The commemorative coins will be a $5 gold coin, a standard-size $1 silver coin, a half-dollar clad coin, and a 5-ounce $1 silver proof coin. The coins will be available in 2019, though the Mint has not yet announced a release date.