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How fast do astronauts return to earth?

Short answer

Astronauts come home at orbital speed: a capsule leaving the International Space Station meets the atmosphere at roughly 28 000 km/h, and air friction rather than engines removes almost all of that within minutes. Parachutes handle the last kilometres, so the touchdown itself is a thump, not an impact.

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Braking with air, not engines

A capsule leaving the International Space Station is moving at about 28 000 km/h, and every bit of that speed has to go somewhere before the crew can stand on the ground. Rockets cannot do it: the propellant needed to cancel orbital speed would rival the propellant needed to reach it. So spacecraft use the atmosphere as a brake. A short engine burn lowers one side of the orbit into the upper air, and from then on friction does the work.

Entry proper begins high in the upper atmosphere. The compressed gas ahead of the heat shield glows, the capsule sheds most of its velocity in a handful of minutes, and the crew feels a steady push of several times their own weight. It is a firm ride rather than a violent one, because the vehicle is shaped to spread the deceleration along a long, shallow path.

The last ten kilometres

Once the speed is down to the range of a fast jet, parachutes take over. Small drogues stabilise the capsule first, then the mains open and the descent slows to something closer to a lift ride. A Crew Dragon comes down under four main parachutes onto water; a Soyuz descends over land and fires soft-landing rockets in the final metre, which is why returning crews describe the arrival as a short, hard thump.

From hatch close to home

The sequence matters more than the clock. On a Soyuz the whole trip, from undocking to sitting in a scorched capsule on the Kazakh steppe, takes a few hours, most of it spent waiting for the right moment to burn; Dragon flights are similar, with the added wait for acceptable sea conditions. Returns from the Moon were faster and hotter, because a spacecraft falling back from lunar distance reaches the atmosphere well above orbital speed, and its heat shield has to absorb the difference.

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