A student shakes a glass of water with an Alka-Seltzer tab in it while conducting an experiment on effervescence, Friday, May 3, 2019 at the Challenger Center in Lanham, MD. NASA astronaut Ricky Arnold helped them carry out the experiment which he also conducted during his 197 day mission onboard the International Space Station (ISS) during Expeditions 55/56. Photo Credit: (NASA/Aubrey Gemignani)