iss043e124238 (4/18/2015) --- NASA astronaut Scott Kelly is seen performing the Space Aging experiment using the Cell Biology Experiment Facility (CBEF) rack in the Japanese Experiment Module (JEM) aboard the International Space Station (ISS). The purpose of the experiment is to study the effects of weightlessness in space flight on the aging of the C. elegans roundworm, a model organism for a range of biological studies. Microgravity causes a number of physiological changes, like heart and bone deconditioning, involving mechanisms that are poorly understood and may affect the rate at which organisms and astronauts age. The Space Aging experiment will grow millimeter-long C. elegans roundworms in microgravity and compare their health and longevity with controlled specimens on Earth.