There was no air to slow them.

The tin cans twinkled as they left the Platform's steel expanse. They
moved away at a speed of possibly 20 to 30 miles an hour. They floated
off in all possible directions. They would never reach Earth, of course.
They shared the Platform's orbital speed, and they would circle the
Earth with it forever. But when they were thrown away, their orbits were
displaced a little. Each can thrown downward just now, for example,
would always be between the Platform and the Earth on this side of its
orbit. But on the other side of Earth it would be above the Platform.
The Platform, in fact, became the center of a swarm, a cluster, a cloud
of infinitesimal objects which would always accompany it and always be
in motion with regard to it. Together, they should make up a screen no
proximity fuse bomb could pierce without exploding.

Joe heard clankings, transmitted to his body through his feet.

"What's that?" he demanded sharply. "It sounds like the airlock!"

Voices mingled in his ears. The other walkie-talkies allowed everybody
to speak at once. Most of them did. Then Joe heard someone laugh. It was
Sanford's voice.

Sandford's aluminized, space-suited figure came clanking around the
curve of the small metal world. The antenna of his walkie-talkie
glittered above his head. He seemed to swagger against the background of
many-colored stars.

Brent spoke quickly, before anyone else could question Sanford. His
tone was mild and matter of fact, but Joe somehow knew the tension