Thursday’s the big day. NASA’s multibillion-dollar Mars rover will arrive at the red planet and almost immediately begin the process of trying to set down safely on the surface.

This is easier said then done. On approach to Mars, the Perseverance rover will shed its cruise stage, retaining only an aeroshell to protect itself and a descent stage. This slimmed-down spacecraft will hit the atmosphere traveling at about 20,000km/hour and have just 410 seconds—or nearly seven minutes—to shed this velocity and make a feathery touchdown.

How to land on Mars

Though the Martian atmosphere is thin, it will nonetheless provide a majority of the resistance to slow Perseverance down. Within about 80 seconds of entering the Martian atmosphere, temperatures outside the aeroshell are expected to reach 1,300° Celsius.