Thomas Collett, University of Portsmouth (VIDEO) University of Portsmouth This video is under embargo. Please login to access this video. Caption Dr. Thomas Collett of the Institute of Cosmology and Gravitation at the University of Portsmouth, explains how they used a nearby galaxy as a gravitational lens to make a precise test of gravity on astronomical length scales. Credit University of Portsmouth 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.