As the ground fills with smoke and steam, Space Shuttle Discovery creates its own fireworks display, fitting for the first ever launch to be made on Independence Day. It was the third launch attempt in four days; the others were scrubbed due to weather concerns. Liftoff on mission STS-121 was on-time at 2:38 p.m. EDT. During the 12-day mission, the STS-121 crew of seven will test new equipment and procedures to improve shuttle safety, as well as deliver supplies and make repairs to the International Space Station. Landing is scheduled for July 17 at Kennedy's Shuttle Landing Facility.