Florida ? Shuttle Discovery’s astronauts surveyed the wings of their ship Monday to ensure a safe descent over the American heartland after leaving the international space station.

On the ride home Wednesday, the space shuttle will make the first coast-to-coast re-entry since Columbia shattered in the sky over Texas in 2003 and sent tens of thousands of pounds of wreckage raining down on at least two states.

Discovery was not supposed to re-enter over the entire United States – just Florida after zooming up from the southwest over Central America and the Caribbean. But that original plan would have entailed a pre-dawn landing, and shuttle commander Pamela Melroy preferred a safer, easier touchdown in daylight, shuttle program manager Wayne Hale said at Cape Canaveral.

This 15-day mission is longer than most – and more stressful, too, with the astronauts’ impromptu repair to the torn solar wing at the space station. As a result, crew fatigue must be considered, Hale said.

Discovery’s new path will have it descending early Wednesday afternoon over the Canadian coast and the Pacific Northwest, down across the Midwest and the South, and on into Florida.