From the Ground Up: Building an Earth Science Satellite (Part 3) Before a satellite is launched into orbit, scientists use instruments on NASA aircraft to calibrate, validate, and refine sensors that are part of current and future satellite payloads. In this video, data systems analyst Eric Fraim explains how an instrument called MASTER (MODIS Airborne ASTER Simulator) is being used to further develop Earth observing satellites. Flying on board NASA’s high-altitude ER-2, MASTER can detect therma