HALO (IMAGE) Johannes Gutenberg Universitaet Mainz Caption HALO in the twilight: Scientists working on board the HALO research aircraft plan to measure the composition of the atmosphere of the northern and southern hemispheres to learn more about the differences in circulation in the two hemispheres. Credit Thorsten Kaluza Usage Restrictions This image may only be used in connection with the press release " HALO mission investigates ozone depletion and processes affecting our climate", issued by Johannes Gutenberg University Mainz on September 26, 2019. 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.