Icy satellites (IMAGE) Southwest Research Institute Caption A study co-authored by Southwest Research Institute Senior Research Scientist Dr. Jason Hofgartner explains the unusual radar signatures of icy satellites orbiting Jupiter and Saturn. Their radar signatures, which differ significantly from those of rocky worlds and most ice on Earth, have long been a vexing question for the scientific community. Credit NASA/JPL-Caltech/SwRI 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.