STS-135 Atlantis — final Space Shuttle mission

At 5:57 a.m. on 21 July 2011, twin sonic booms rolled across the Florida darkness one last time. Atlantis dropped out of the pre-dawn sky, flared over Runway 15 at Kennedy Space Center, and rolled to a stop. In the cockpit, commander Chris Ferguson keyed his microphone: mission complete. Thirty years and 135 flights after Columbia first thundered off Pad 39A in April 1981, the Space Shuttle program was over.

The final mission had begun on 8 July, when nearly a million spectators lined the Space Coast to watch Atlantis climb away from the same Pad 39A. The crew numbered just four, the smallest shuttle crew since 1983, for a sobering reason: no second orbiter remained to fly a rescue. Had Atlantis been damaged, Ferguson, Hurley, Magnus and Walheim would have sheltered aboard the International Space Station and come home one at a time in Soyuz seats. Their cargo, the Italian-built Raffaello module, carried more than 9,400 pounds of supplies, enough to provision the station for a year.

Before departing, the crew left something behind: a small American flag that had flown on STS-1 in 1981, mounted on the station's Harmony hatch as a prize for the next crew to launch from American soil. The wait stretched nine years. When the flag finally came down in 2020, the hand that retrieved it belonged to Doug Hurley, the pilot of STS-135 himself, arriving aboard SpaceX's Crew Dragon on its first crewed flight.

Atlantis rolled into retirement after 33 missions and now stands in a museum a few miles from the runway where it stopped. The orbiters had built the ISS, launched and serviced Hubble, and carried hundreds of people to orbit, at the cost of two crews lost. With the fleet grounded, the United States surrendered independent human launch capability and bought seats on Russian Soyuz rockets until the commercial crew era opened in 2020.