A fire on board the International Space Station, or any spacecraft with and oxygen-rich, confined space, would be extremely dangerous, so NASA wants to learn more about how to avoid it.

This week, they'll do a first-ever experiment.

When they're done taking supplies off the unmanned Cygnus cargo vehicle, and after it detaches, they'll remotely trigger a fire on board the vehicle, so they can see what fire does in a zero-g or microgravity environment.

It's never been done on this large a scale before.