1. Recommend defining 'ATV'.
The first mention of 'ATV' is on page 121, under 'AUXILIARY VEHICLES': "The Cronus has no rovers aboard, only two ATVs in her garage..."
(ATV = All-Terrain Vehicle)
2. Recommend defining 'RTV'.
The first and only mention of 'RTV' is on page 134, under 'GARAGE': "Most of the vehicle compliment of the Cronus is missing—there are only two ATVs aboard and no RTVs."
(RTV = Rough Terrain Vehicle)