The rotating gantry at space shuttle launch pad 39A swung away from Endeavour on Tuesday evening, moving the countdown a critical step closer toward Wednesday's planned 6:36 p.m. EDT liftoff.

The service structure retraction began at 8:53 p.m. EDT. Ground crews had the gantry in the park position for launch by 9:45 p.m.

Credit: Ben Cooper/Spaceflight Now

Credit: Ben Cooper/Spaceflight Now

Additional coverage for subscribers:
VIDEO: TIME-LAPSE MOVIE OF GANTRY ROLLBACK PLAY
VIDEO: TUESDAY MORNING'S STATUS BRIEFING PLAY
VIDEO: STS-118 PRE-LAUNCH NEWS CONFERENCE PLAY
VIDEO: MONDAY MORNING'S STATUS BRIEFING PLAY
VIDEO: SUNDAY COUNTDOWN AND WEATHER UPDATE PLAY
VIDEO: CREW ARRIVES AT KENNEDY SPACE CENTER PLAY
VIDEO: COMMENTS FROM EACH OF THE ASTRONAUTS PLAY
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