astronauts return safely – The crew module, where the astronauts live, orbits the Earth at a high velocity of about 7,800 m/s. When the module returns to Earth and re-enters the atmosphere, it faces the challenge of reducing its kinetic energy.

Atmospheric drag itself acts as the primary brake and saps away most of its energy through aerobraking. To further reduce its velocity for a soft landing, after the module reaches the desired altitude (below 12 km), a multi-stage parachute system launched by a pyro-actuated mortar is deployed.

A typical recovery system includes all the items needed to soft-land the module at sea or on land after the aero braking phase. This includes a parachute, instruments to detect where the module has fallen, and an up-right system to maintain the module’s orientation in the event of a sea landing. SpaceX-Dragon, Gaganyaan and NASA Orion Crew Module are typical examples of sea landings.