The Soyuz spacecraft has three compartments. Each of them has different architecture and a specific purpose: -Orbital Module: also called the living compartment, it is equipped with sleeping bags, food, water, and a toilet. It has a volume of 230 cubic feet (6.5 m3). -Instrument Compartment: it is not accessible to the astronauts. It houses the oxygen and propellant tanks, thrusters, the onboard computer, and a number of sensors. -Descent Module: it is where the cosmonauts and astronauts sit for launch, re-entry, and landing. All the necessary controls and displays of the Soyuz are located here. The module also contains life support supplies and batteries used during descent, as well as the primary and backup parachutes and landing rockets. While returning back to Earth, the crew occupies this central element. The other two modules are jettisoned prior to re-entry. They burn up in the atmosphere, so only the Descent Module returns to Earth. It has a periscope mounted on the outside, which allows the crew to view the docking target on the station or the Earth below. It also has a guidance, navigation and control system to maneuver the vehicle during the descent phase of the mission. This module weighs 6,393 pounds (2900 kg), with a habitable volume of 141 cubic feet (4 m3). The descent module experiences extremely high temperatures during re-entry. So to protect the crew inside and the module itself, it is fitted with a special protective coating and has a heat shield on its base. Even though it doesn’t have wings, the Soyuz descent capsule is able to change the way it flies through the air after re-entry. The capsule’s lift increases when it rotates in one direction and decreases if it rotates in the opposite direction. In this way, it is able to keep to its planned trajectory.