fully deployed in space, with its two solar panel "wings" extended, Mariner R was 12 ft in height and 16.5 ft across. The main body of the craft was hexagonal with six separate cases of electronic and electromechanical equipment:

*Two of the cases comprised the power system: switchgear that regulated and transmitted power from the 9800 solar cells to the 33.3 lb rechargeable 1000 watt silver-zinc storage battery.
*Two more included the radio receiver,