MARSBOX (IMAGE) Frontiers Caption MARSBOx payload in the Earth's middle stratosphere (38 km altitude). The shutter is open exposing the top layer samples to UV radiation. Credit NASA Usage Restrictions Credit NASA License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.