The shape of 2001 Mars Odyssey is anything but uniform, but its size can most easily be visualized by mentally placing the spacecraft inside of a box. Pictured this way, the box would measure 2.2 meters (7.2 feet) long, 1.7 meters (5.6 feet) tall and 2.6 meters (8.5 feet) wide. At launch Odyssey weighed 725.0 kilograms (1598.4 pounds), including the 331.8-kilogram (731.5-pound) dry spacecraft with all of its subsystems, 348.7 kilograms (768.8 pounds) of fuel and 44.5 kilograms (98.1 pounds) of instruments.
The framework of the spacecraft is composed mostly of aluminum and some titanium. The use of titanium, a lighter and more expensive metal, is an efficient way of conserving mass while retaining strength. Odyssey's metal structure is similar to that used in the construction of high-performance and fighter aircraft.
Most systems on the spacecraft are fully redundant. This means that, in the event of a device failure, there is a backup system to compensate. The main exception is a memory card that collects imaging data from the thermal emission imaging system.
More detailed information about the spacecraft: