Mars 2020 to attempt to make oxygen for future manned missions
Nasa's next Martian rover will attempt to make oxygen on the surface of the red planet when it lands there in 2021 and will carry seven other scientific projects among which seeking life and storing samples.
Among them is a device for turning the CO2 that dominates the thin Martian air into oxygen.
This could support human life or make rocket fuel for return missions.
"This is a really exciting day for us," said astronaut and Nasa administrator John Grunsfeld, announcing the Mars 2020 scientific payload in Washington DC.
The one-tonne, $1.9bn vehicle is modelled on Curiosity, the rover that touched down on the red planet in August 2012 with a few downsized adjustments. Some of that space will be used to package up cylindrical rock samples drilled from the planet's surface.
An oxygen supply would also be essential if people were to land on the planet.