NASA Tests Rover Concepts in Arizona A collection of engineers, astronauts and geologists have spent the past week testing out the Small Pressurized Rover in the 11th annual Desert RATS – or Research and Technology Studies — field tests. Two teams of one astronaut and one geologist each have been driving the rover through the Arizona desert, trying it out in two different configurations. One configuration leaves the crew members free to get on and off the rover whenever they like, but they must wear spacesuits at all times to protect them from the lunar environment. The second configuration — called the Small Pressurized Rover, or SPR — adds a module on top of the rover’s chassis that the crew can sit inside as they drive the vehicle, donning spacesuits whenever they want to get out. For the first week of tests, the rover has been driven on day-long trips to determine how each configuration performed. These have been some of the longest drives the prototype has ever made, but next week the group will step it up another notch or two, by going on a three-day drive through the desert in the SPR to determine how it performs and whether it's comfortable enough for long-duration trips.