The end of an era is near. The U.S. space shuttles - the complex workhorses of the U.S. space program - are being retired so NASA can focus on developing spacecraft that can travel beyond low-Earth-orbit. The space shuttle Atlantis is set to lift off on July 8 - the final launch in the 30-year-old shuttle program. We have more on the 12-day mission to carry supplies and spare parts to the International Space Station.
These four astronauts are about to make an historic journey. Mission Specialist Rex Walheim, Commander Chris Ferguson, Pilot Doug Hurley and Mission Specialist Sandra Magnus make up the last crew to fly aboard a NASA space shuttle.
Magnus remembers when she first saw a space shuttle roar into the skies back in 1981.
"I was in high school, and it was just, you know, pretty spectacular to see something launching with people in it, even on TV," said Magnus. "It was like, 'Wow, look at that! You know, that's really cool. It looks like an airplane, but it's launching like a rocket. Wow!' You know, it was really different."
All members of this Atlantis crew have flown on space shuttles before. But this time it is different, because NASA is retiring the shuttle fleet at the end of this mission.
Commander Ferguson spoke to reporters during a brief break in training.
"We're very honored to be in this position," said Commander Ferguson. "You know, there are many people who could be here. We just happened to...when the dice fell, our names were facing up. So we consider ourselves fortunate, lucky. I think - and we haven't talked about this - I think each of us feels, perhaps, a little extra burden to make sure we put on the best possible face forward for the last go-around of this. And the crew is very prepared."
The astronauts readied for this mission with ascent training in a simulator, water survival training, running through emergency scenarios - such as a fake fire on a mock-up of the space station, preparing in virtual reality labs and more simulators, reviewing the tools they might need in space and practicing post-landing exits from a mock-up of the shuttle.
The crew says it is ready for this final mission.
"We're going to go out and do a fantastic job and, like I said, when it's all over at the very end, I think that's when the enormity is going to hit us. You know, that last wheelstop call is going to be a little tough."
This last shuttle flight will help to restock the International Space Station," said Ferguson. "Although NASA is retiring its shuttle fleet, the United States has committed to funding the space station through 2020.
The orbiting lab is as capable as it is today because of the shuttle program, says Magnus.
"Now you'll see this huge monster building in space," she said. "You will see science racks and experiment facilities that are on board because the shuttle could take them there."
The space outpost where people have lived continuously for more than a decade remains a visible legacy of the 30-year-old shuttle program.