As a prelude to its plan to return U.S. astronauts to the moon’s surface for the first time since 1972, the National Aeronautics and Space Administration has asked several space-robotics companies to design their own pod-like lunar landers to ferry scientific instruments and gear to the surface without a crew. At least two of these commercial entities also plan to send up art, though it’s unclear which one will be ready to launch first.

The lander with Mr. Koons’s art is pledged to hitch a ride aboard a Falcon 9 rocket provided by Elon Musk’s SpaceX, while Mr. Jafri’s project will fly on a Vulcan Centaur rocket designed by United Launch Alliance, a joint venture between Lockheed Martin and Boeing Co.