Volunteer and Researcher (IMAGE) UT Southwestern Medical Center Caption Volunteer Wendy Hancock, left, and researcher Dr. Lonnie Petersen hang on to supports during a zero-gravity interval. Credit UT Southwestern Medical Center Usage Restrictions None 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.