In order to determine the location of the leak, the crew had been sealing off small peripheral modules of the space station while Mission Control looked for accelerated pressure drops inside the sealed-off sections.

MSN: Crew finds ��culprit�� in space station leak

The station's crew, as well as engineers at SpaceX's mission-control center at its Hawthorne, Calif.

WSJ: SpaceX Craft Rehearses Moves

The system is there to give Houston a direct communication link to the station in the early stages of construction (otherwise, everything must funnel through Mission Control outside Moscow).

CNN: liftoff