Kevin Mark, Orbiting Carbon Observatory 3 (OCO-3) purge engineer with NASA’s Jet Propulsion Laboratory, fastens a separate fixture of OCO-3, stored apart from its payload container, to a truck for transport from the Space Station Processing Facility high bay at the agency’s Kennedy Space Center in Florida to the SpaceX facility on March 18, 2019. The OCO-3 payload will be stowed in the trunk of SpaceX’s Dragon spacecraft, where it will launch aboard a Falcon 9 rocket on the company’s 17th Commercial Resupply Services mission to the International Space Station. Launch is scheduled for April 25, 2019, from Launch Complex 40 at Cape Canaveral Air Force Station. Once the payload reaches the station, it will be removed from Dragon and robotically installed on the exterior of the orbiting laboratory’s Japanese Experiment Module Exposed Facility Unit, where it will measure and map carbon dioxide from space to provide further understanding of the relationship between carbon and climate.