Astronaut Ricky Arnold at Six Flags America

NASA astronaut Ricky Arnold, center, and Smithsonian National Air and Space Museum's Beth Wilson, left, and Marty Kelsey, right, jump backwards as a model volcano erupts with fire during a Stem in 30 segment, Friday, May 3, 2019 at Six Flags America theme park in Upper Marlboro, MD. During Expedition 55/56, Arnold completed three spacewalks for a total of 19.5 hours outside the space station, and concluded his 197 day mission when he landed in a remote area near the town of Zhezkazgan, Kazakhstan in Oct. 2018. He also flew to the space station on shuttle mission STS-119 to deliver the final pair of power-generating solar array wings. Photo Credit: (NASA/Aubrey Gemignani)