Cape Canaveral, Fla. ? NASA hauled Discovery to the launch pad Friday in preparation for only the second liftoff of a space shuttle since the Columbia disaster three years ago.

Discovery’s trek of a little more than four miles from the Vehicle Assembly Building took almost eight hours. The shuttle, attached to an orange fuel tank and two solid rocket boosters, moved toward the pad atop a gigantic transport vehicle that resembled four supersized bulldozers.

The move was a major step toward a liftoff between July 1 and July 19.

Shuttle program manager Wayne Hale said he was confident that Discovery would fly in July and that NASA would be able to launch two more shuttle flights by the end of the year.