Shuttle Discovery takes a piggyback ride into posterity

Image: Space Shuttle Discovery flies over the U.S. Capitol
Space Shuttle Discovery, mounted atop a 747 shuttle carrier aircraft, flies over the U.S. Capitol during a flyover of the nation's capital on its final trip to its retirement place in Washington, DC. Win Mcnamee / Getty Images

Sitting on top of a modified Boeing 747 jet, the shuttle Discovery made a sentimental journey on Tuesday, visiting its old haunts in Florida as well as its new environs around the nation's capital. And thousands thronged to see it pass.

Tuesday's flight began just after dawn at NASA's Kennedy Space Center in Florida and ended at midday at Washington Dulles International Airport, adjacent to the Smithsonian National Air and Space Museum's Steven F. Udvar-Hazy Center in Virginia.

Over the next two days, the world's most traveled space plane will be lifted off its perch on NASA's Shuttle Carrier Aircraft and readied for Thursday's official handover to the Smithsonian.

Although Discovery hasn't flown in space since its final mission to the International Space Station, more than a year ago, the ferry flight was even more definitive as a signal that a 30-year era in spaceflight was finally going into the history books.

"It's kind of bittersweet," said Henry Taylor, one of the flight engineers on the Shuttle Carrier Aircraft. "This is the last flight, but it's great to have it here at the museum for people to see."

NASA's deputy administrator, Lori Garver, put a positive spin on the proceedings: "We're very proud," she told me. "I like to equate it to your child going off to college."

In a flood of social-media updates, witnesses to the final flight wondered whether Discovery's retirement also signaled that America's space aspirations were fading. Garver would have none of that.

"To those who say our best days of space exploration are behind us, I simply must disagree," she told dignitaries, journalists and other guests assembled on the runway alongside the shuttle-jet combo. She pointed to NASA's future plans to go beyond Earth orbit, and eventually to a near-Earth asteroid and beyond.

Nevertheless, Tuesday's events were clearly more of a time to look back than to look ahead. Among those in the crowd was Ron Bledsoe, a 38-year-old resident of Manassas, Va., who was one of 50 people invited to the landing as part of a promotion for the Dulles airport's 50th anniversary.

"I feel like a 10-year-old kid again," Bledsoe told me.

He wasn't alone. Thousands turned out to cheer the shuttle's flight — first at Kennedy Space Center, where about 2,000 shuttle program veterans paid their last tribute to Discovery. Still more watched the skies from Florida's Space Coast, where Discovery lingered before heading up the East Coast.

In Washington, the National Mall filled with onlookers who watched the shuttle-jet combo fly over the U.S. Capitol, the White House and other historic monuments at an altitude of 1,500 feet. "Oh my God, look at that," Terri Jacobsen of Bethesda, Md., told The Associated Press when she first spotted the double-decker craft. "That thing is mammoth."

"It was pretty amazing," her 12-year-old son, Riley, said later. "Pretty freaking crazy. It looked like it was inflated."

bThe Smithsonian's curator for shuttle artifacts, Valerie Neal, was all smiles when Discovery and its carrier airplane touched down at Dulles, a little more than four hours after its Florida takeoff. Discovery will take the place that had been held by the shuttle Enterprise, a prototype shuttle that was handed over to the Smithsonian in 1985.

On Thursday, Discovery and Enterprise will be displayed together outside the Udvar-Hazy Center. In an interview, Neal mused over the place that the shuttles will hold in history for future generations.

"I'd love to be here 100 years from now," she said. "People might say, 'Well, isn't that quaint?'"

There's nothing quaint about Discovery's 28-year history as a spaceship: The orbiter has flown 39 missions, more than any other single spacecraft. It has logged more than 148 million miles of travel, over more than a year's worth of days in space.

Discovery's list of achievements includes delivering the Hubble Space Telescope to orbit, carrying the first Russian cosmonaut to launch on a U.S. spaceship, performing the first rendezvous with Russia's Mir space station (with the first female shuttle pilot in the cockpit), returning Mercury astronaut John Glenn to orbit, and bringing shuttle flights back to life after the Challenger explosion in 1986 and the Columbia tragedy in 2003.

Three more shuttle shifts remain: Enterprise will be ferried to New York City as early as next week and will eventually go on display at the Intrepid Sea, Air and Space Museum. The shuttle Endeavour will be flown to the California Science Center in Los Angeles this fall. Atlantis will have the shortest journey of all: It will be towed from NASA's Kennedy Space Center to the nearby visitor center in Florida.

With the shuttles in retirement, 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 California-based SpaceX, is set to launch from Florida on April 30.

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.

Follow , on Twitter (). This report includes information from The Associated Press.