How do astronauts go to the bathroom? It’s a question children have wondered for years, and now NASA wants help creating a better way.

In a statement posted on their website, NASA is calling on the entire world to submit design concepts for compact toilets that can operate in both microgravity and lunar gravity.

NASA is preparing to return to the Moon by 2024 as part of project Artemis, and as they upgrade other aspects of the flight, they are seeking new ideas for toilet facilities when astronauts are in the cabin and out of their spacesuits.

Specially-designed toilets exist on the International Space Station already, however according to NASA, they were designed for microgravity only.

NASA and HeroX are offering financial and merchandise rewards for winning design concepts in this Lunar Loo contest.

Details about how to enter the contest can be found here.