SpaceX, Blue Origin, and NASA have their work cut out for them. Getting to Mars is easier said than done, says retired NASA astronaut Chris Hadfield.
Buzz60, USA Today: Nation
Tue, 06/19/2018 - 9:09am
SpaceX, Blue Origin, and NASA have their work cut out for them. Getting to Mars is easier said than done, says retired NASA astronaut Chris Hadfield.