An eddy of fresh air told him without looking that the door had cycled open.

The door cycled open, revealing the great spherical chamber beyond.

The door cycled open and he stepped back into prison.

The air pressure went to zero, the outer hatch cycled open, and George looked out across the rocks.

When the hatch cycled open, something moved in the dark interior.

Took cautiously peered out the airlock door as it cycled open.

The door appeared in the blank far wall and cycled open.

After a brief wait the door cycled open and Joe entered.

He hit the airlock controls, and the outer door cycled open.

The lock cycled open and a small, lonely figure emerged.