Europa Clipper's thermal imager (IMAGE) Arizona State University Caption E-THEMIS lead scientist Philip Christensen stands next to the box-like "tent" that surrounds both E-THEMIS (left) and its optical test equipment. With the tent doors closed and sealed, the team can flood the tent with dry nitrogen gas to remove all water vapor inside. This lets engineers accurately test E-THEMIS' thermal sensitivity, which water vapor greatly interferes with. Credit Charlie Leight/ASU News Usage Restrictions No restrictions. License Public Domain 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.