Why would a spacewalking astronaut float off if not tethered to the craft?

Asked by: C Soutar, Kirriemuir

We have Newton’s first law of physics to thank for this. It says that a body stays in its present state of motion until acted on by an external force. So, in the vacuum of space, an astronaut without a line tying him to his ship will drift in the same direction forever unless something pulls or pushes them to safety.

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