Pinpointing STEVE's origins (IMAGE) University of Colorado at Boulder Caption Analysis of citizen scientist photos of a 2018 STEVE event show the purple and green light emissions occur at different altitudes but along the same magnetic field lines. This indicates they’re driven by the same region of the magnetosphere nearly 30,000 kilometers above Earth’s surface. Credit Neil Zeller via Chu et al. 2020. Usage Restrictions Use with creddit License Original 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.