Discovery shuttle on final voyage

(ROUGH CUT -- NO REPORTER NARRATION)

The space shuttle Discovery took off on its final voyage on Tuesday (April 17), on a piggyback jet ride to the Smithsonian National Air and Space Museum's Virginia annex.

The United States retired its space shuttles last year after finishing construction of the 100 billion U.S. dollar International Space Station, a project of 15 countries, to begin work on a new generation of spaceships that can carry astronauts to destinations beyond the station's 240-mile-high (384-km-high) orbit.

Discovery, the fleet leader of NASA's three surviving shuttles, completed its last spaceflight in March 2011. It was promised to the Smithsonian Institution's National Air and Space Museum in Washington, D.C., the nation's official repository for space artifacts.

For its last ride, Discovery took off not from its seaside launch pad but atop a modified Boeing 747 carrier jet that taxied down the Kennedy Space Center's runway at dawn. The shuttle's tail was capped with an aerodynamically shaped cone and its windows were covered.

Discovery, which first flew in August 1984, will then be transferred to the Smithsonian's nearby Steven F. Udvar-Hazy Center in Chantilly, Virginia.