When floating in their spacesuits, astronauts wear an absorbent diaper that can keep them going through a full day.

Within a spacecraft like the International Space Station (ISS), zero gravity toilets are also available to collect liquid and solid waste despite the weightless environment. In weightlessness, fluids blob up and stick to surfaces, while solids float in the air.

This space toilet on the ISS malfunctioned in 2008

If ever the pressure system of these toilets were to malfunction, the ISS could always re-enter gravity within a few hours, as it is in orbit near the Earth.

But now that NASA is planning missions deeper into space, the American space agency needs to find another system to collect human waste. Diapers would be useless in case of emergency there, as waste that's in contact with the body for too long can cause life-threatening infections.

The space agency has launched a competition called the Space Poop Challenge to finally ditch the diaper. "What's needed is a system inside a spacesuit that collects human waste for up to 144 hours and routes it away from the body, without the use of hands," said a NASA spokesperson.

Aspiring inventors can submit their ideas until December 20, and NASA will reward the three best solutions with a prize of $30,000 (over 28,000 euros).

In the forum of the Challenge page, poop innovators are sharing ideas and questions, asking for an example of which type of poop is most frequent, if a unisex model is possible and if astronauts wear underwear under their spacesuits.





eg/cmk (AFP, dpa)