Comet 21P/Giacobini-Zinner (IMAGE) Far Eastern Federal University Caption Comet 21P/Giacobini-Zinner is moving against the background of static stars. A telescope is following the comet, not the stars. That's why tracks of the stars in the picture are stretched images. Credit The frame has taken by Ussuriysk Astrophysical Observatory 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.