NASA begins moving shuttle

CAPE CANAVERAL, Fla. -- NASA began moving Discovery to the launch pad Friday in preparation for its liftoff sometime between July 1 and July 19.

It will be the second liftoff of a space shuttle since the Columbia disaster three years ago.

Discovery's trek of a little more than 4 miles was expected to take about seven hours aboard a crawler-transporter. The shuttle weighs about 4.5 million pounds.

After Discovery's mission last summer, the shuttle fleet was grounded because foam insulation was still snapping off the external fuel tank, as it did on Columbia. A chunk of foam knocked a hole in the wing of Columbia, causing the spacecraft to shatter as it returned to Earth.

killing all seven astronauts.