Updated

Space shuttle Discovery is preparing to move into its new home at the Smithsonian's National Air and Space Museum annex in northern Virginia.

Thursday morning, the world's most traveled spaceship will be lifted off its Boeing 747 carrier and towed to the museum near Dulles International Airport. Astronauts including former Sen. John Glenn will help deliver Discovery to its retirement as an artifact representing the 30-year shuttle program.

A welcome ceremony is expected to draw thousands of visitors who want an up-close look at the shuttle after it flew over the Washington area Tuesday. The museum is hosting a four-day festival to showcase Discovery.

Curator Valerie Neal says Discovery will be displayed as if it just landed. There will be an interactive display giving visitors a look inside the shuttle.

Space shuttle Discovery buzzed metropolitan Washington, D.C., Tuesday morning, soaring over the Washington Monument, the White House and the Capitol before landing to begin its new life as a museum relic -- following three decades of space service for NASA's oldest and most traveled shuttle.

Thousands had packed the National Mall in front of the Capitol to watch the pair swoop by, as Discovery took a leisurely spin at an easy-to-spot 1,500 feet overhead.

Discovery departed Florida's Kennedy Space Center at daybreak Tuesday aboard a modified jumbo jet bound for Washington, where it will become a Smithsonian exhibit. The shuttle-jet combo is set to land at Dulles International Airport.

Nearly 2,000 people -- former shuttle workers, VIPs, tourists and journalists -- gathered along the old shuttle landing strip earlier in the morning to see Discovery off. A cheer went up as the plane taxied down the runway and soared into a clear sky.

The plane and shuttle headed south and made one last flight over the beaches of Cape Canaveral -- thousands jammed the shore for a glimpse of Discovery -- then returned to the space center in a final salute. Cheers erupted once more as the pair came in low over the runway it had left 20 minutes earlier and finally turned toward the north.

A similar flyover was planned over the monuments in the nation's capital, later in the morning.

Discovery -- the fleet leader with 39 orbital missions -- is the first of the three retired space shuttles to head to a museum. It will go on display at Dulles International Airport in Virginia, taking the place of the shuttle prototype Enterprise. The Enterprise will go to New York City.

Endeavour will head to Los Angeles this fall. Atlantis will remain at Kennedy.

NASA ended the shuttle program last summer after a 30-year run to focus on destinations beyond low-Earth orbit. Private U.S. companies hope to pick up the slack, beginning with space station cargo and then, hopefully, astronauts. The first commercial cargo run, by Space Exploration Technologies Corp., is set to take place in just another few weeks.

For at least the next three to five years -- until commercial passenger craft are available in the United States -- NASA astronauts will have to hitch multimillion-dollar rides on Russian Soyuz capsules to get to the International Space Station.