Discovery, the oldest surviving space shuttle of NASA’s fleet, is about to embark on her last journey- to the Smithsonian Institution.

Discovery’s maiden voyage was launched in 1984, and she has traveled to outer space 39 times since then. Her experience makes her the number one shuttle in history, completing more missions in our solar system than any other.

Discovery’s feats include delivering the Hubble Space Telescope to orbit; connecting with Mir, the Russian space station with the first female shuttle pilot; being the first U.S. spaceship to launch a Russian cosmonaut; boosting shuttle flights after the Challenger and Columbia tragedies; and returning John Glenn to orbit.

Discovery will arrive at the Smithsonian’s hangar via a modified jumbo jet, after a farewell flight over Cape Canaveral and Washington D.C. Security officers, firemen, shuttle workers and, of course, Discovery’s last astronaut crew all gathered at Kennedy Space Center to say their goodbyes.

“It’s good to see her one more time, and it’s great that Discovery is going to a good home. Hopefully, millions of people for many, many years to come will go see Discovery,” Steven Lindsey, the last astronaut to command the shuttle, said emotionally. “It’s also sad…it’s sad to see that the program is over.”

Discovery will replace Enterprise, the spaceship prototype that was used only in landing tests over four decades ago. Enterprise will go on display in New York’s Intrepid Sea, Air, and Space Museum.

Stephanie Stilson, a NASA manager, said “To see her like this is quite an amazing site. We’re finally here.” She added that it’s been almost exactly one year since Discovery’s last mission.

Still, “there’s no denying the sadness associated with it,” according to another of Discovery’s last crew.

The crew of a long-duration isolation study finally “landed” back on earth to be greeted by daylight and applause after living 520 days, or seventeen months, in a simulation of space travel to Mars.

The Mars500 experiment, which cost $15 million, aimed to test whether humans could stay physically and mentally healthy during the months of travel to Mars.

Six male volunteers from Europe, Russia and China took part in the experiment. On Friday, they emerged from their cells red eyed but smiling, and were allowed to greet friends and family briefly before being sent into a three-day quarantine.

“It’s really, really great to see you again, rather heartwarming,” said Diego Urbina, an Italian-Colombian participant. “On this mission we’ve achieved the longest isolation ever so that humankind can go to a distant but reachable planet.

Psychologists worry that the noise and activity of normal life will shock the would-be astronauts greatly.

“Time seems to have flown by since we closed the hatch last year. But how time really felt to the crew we’ll soon know. Probably we’ll have a very big difference of opinion,” said Igor Ushakov, head of the Russian Institute for Biomedical Problems, which ran the experiment.

Having fed on real astronauts rations, rarely showered and taken daily urine and blood samples, the men felt truly distant from Mission Control.

“I felt a physical distance between out crew and the people in Mission Control. My reasoning knows that they’re just 20 m away from us but my mind can’t accept it.”