Close-up of tracker (IMAGE) Massachusetts Institute of Technology Caption A close-up of the tracker shows that it is Y-shaped and has 3 metallic discs. The tracker is at the end of a yellow strip-cable. Credit Canan Dagdeviren Usage Restrictions Credit must be given to the creator. No derivatives or adaptations of the work are permitted. License CC BY-ND 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.