Solar Coronal Loops (IMAGE) University of Sheffield Caption Magnetic coronal loops form a solar harmonica with temperature over a million degrees. The average length of these loops are a few 100,000 km. Credit Image credit TRACE 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.