Astronauts who flew on the space shuttle program's final mission 15 years ago this month say its legacy lives on, especially in the International Space Station and Hubble Telescope.
"The last 30% of the shuttle flights were dedicated to building the space station," said STS-135 Cmdr. Chris Ferguson. "So I'd have to say that the shuttle's legacy really was what it left behind in the space station that's been in use for 20-plus years."
STS-135 marked the end of the three-decade program. The crew of four reunited Saturday at the Kennedy Space Center Visitor Complex beneath the Space Shuttle Atlantis, the orbiter that took them on a 12-day mission to them ISS and back.
"We went through such an incredible experience together, and to be back here together, it just brings back so many memories," said mission specialist Rex Walheim. "And then you just look at that beautiful vehicle that we got to fly. It's just an amazing experience to be back together and to be here."
Hundreds of people gathered beneath the shuttle exhibit to hear from Walheim and the rest of his NASA crew: Ferguson, pilot Doug Hurley and mission specialist Sandy Magnus. The conversation was moderated by Mike Leinbach, NASA's shuttle launch director.
The STS-135 mission launched from Kennedy Space Center on July 8, 2011. The bulk of the mission was spent restocking the space station with around 9,600 pounds of supplies, spare parts and hardware. It returned to KSC on July 24, 2011, marking the end of the program.
For Ferguson, the shuttle's legacy lives on in orbit.
Over the course of its 135 missions, the space shuttle program helped build the space station and launched important satellites into orbit, including the Hubble Telescope.
"All the discoveries that Hubble's been making wouldn't have been possible without this vehicle to take her up," Walheim said. "So it lives on in that respect."
The shuttle also carried five missions designed to service Hubble after a flaw in its main mirror was discovered in space.
"The very design of the shuttle provided the program with lots of opportunities to flex and transition to different types of missions," Magnus said.
With the shuttle program ended, NASA relied on the Russian Space Agency to transport astronauts to the International Space Station. The agency awarded contracts to two commercial companies – SpaceX and Boeing – to develop new capsules for astronaut launches.
SpaceX would launch its first human mission nearly nine years after that final shuttle touchdown. STS-135 pilot Doug Hurley commanded the SpaceX Crew Dragon mission, which launched May 30, 2020.
After retiring from NASA, Ferguson joined Boeing and was slated to fly on the company's first crewed Boeing space flight. But in 2020, he stepped down from the mission, citing personal reasons.
Speaking with Central Florida Public Media on Saturday, Ferguson said the program's delay led to his decision.
"For me personally, with Boeing, it just strung out too long," he said. "I had a much shorter time horizon where I wanted to do something like that, and it doubled, and maybe even went beyond double. So you know that was a tough personal decision I had to make. I have no regrets. It was the right thing to do for my family and me personally."
Instead, NASA's Butch Willmore and Suni Williams flew the crewed test mission in June 2024. NASA and Boeing uncovered hardware issues with the spacecraft and returned it without a crew. Willmore and Williams returned home in SpaceX's capsule instead.
Ferguson is still affiliated with Boeing, consulting on safety for the company. While STS-135 was likely his last mission to orbit, he still recalls fondly his time in space.
"There is nothing that is more magical than being in space, and I loved my time on the International Space Station," he said.
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