In context: Space toilets already exist, mind you, at the International Space Station, but they are designed solely for use in microgravity. NASA needs something that works both in microgravity and lunar gravity and is turning to the global community at large to help identify a suitable solution for both environments.
NASA's Artemis program intends to put "the first woman and the next man" on the Moon by 2024. That may seem far off but in actuality, it's just around the corner and there is still a wealth of preparation that needs to be carried out before it can happen.
One such issue that needs to be solved is using the toilet.
A generally straightforward task here on Earth, using the restroom becomes an incredibly complex matter in space when in microgravity. And it's an entirely different experience on the Moon where the gravity is about 1/6 that of what we experience on Earth.
Those interested in submitting an idea need to do so before August 17. Winners will be selected over the following month and announced on September 30, 2020. Full design specifications and guidelines can be found over on the challenge website.