How Soyuz Powers Missions to the International Space Station

The Soyuz spacecraft, a cornerstone of human spaceflight since 1967, is a Russian-designed vehicle that ferries astronauts and cosmonauts to the International Space Station (ISS) and back. Launched atop a Soyuz rocket from Baikonur Cosmodrome in Kazakhstan, it comprises three modules: the orbital module, descent module, and service module.

The orbital module, a spherical section at the spacecraft’s front, houses equipment for docking with the ISS and provides living space during orbit, but it is discarded before reentry. The descent module, located in the middle, is where the crew of up to three resides during launch and reentry. It features a heat shield, parachutes, and braking engines to ensure a safe, albeit bumpy, landing in Kazakhstan’s steppes. The service module, at the rear, contains propulsion, life support, and power systems, including solar panels and batteries, and is also jettisoned before reentry.

The Soyuz, weighing 7 tons and measuring 7.2 meters long, reaches orbit in just nine minutes after launch, with the rocket separating post-launch. The journey to the ISS can take six hours or two days, depending on the mission profile, while return trips last about 3.5 hours.