Why do astronauts float if gravity still exists?
Space looks gravity-free. The truth is stranger: orbit is a kind of falling.
Why do astronauts float if gravity is still there?
An orbiting spacecraft looks weightless. But Earth's gravity hasn't switched off. What's really happening?
Imagine you're inside a spacecraft orbiting Earth.
You release a pencil. Instead of falling to the floor, it floats beside you. Does that mean there's no gravity?
Astronauts aboard the International Space Station are still pulled strongly by Earth’s gravity.
What's really going on?
At the station’s altitude, Earth’s gravitational pull is still substantial. The astronauts are not floating because gravity has vanished.
The station is moving sideways so quickly that, while it falls toward Earth, the planet curves away beneath it. The spacecraft and everything inside it fall together, creating apparent weightlessness.
This is called continuous free fall. Orbit needs gravity: without it, the station would continue along a straight path rather than curving around Earth.
If gravity vanished instantly, would the station keep orbiting?
Reveal the explanation
No. Without gravity to bend its path, it would move approximately in a straight line.
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