- Who
- Mars Exploration Rovers
- Where
- Not Applicable ()
- When
The twin Mars Exploration Rovers Spirit and Opportunity could technically rotate their wheels at 5 cm per second. However, in practice they were never operated that fast. The top speed at which the Mars Exploration Rovers were ever commanded to drive in a straight line was 3.7 cm per second, or 133 meters per hour. Driving is a very energy-intensive activity and quickly drain the rovers' batteries. Driving also requires the motors to be warm. Therefore, most drives took place in the peak temperature hours of the afternoon, when the Sun would have heated up the motors to operating temperature.
