Filaments are cool clouds of solar material that are moved across the Sun's surface by magnetic forces. If straightened out, the filaments shown in the picture would stretch for the Sun's entire diameter, which is equal to about a million miles.
Filaments can float for days on end without changing , but can also erupt unexpectedly. These eruptions emit solar material that either falls back onto the Sun's surface or is released into space. If the material escapes from the Sun, it forms fast-moving clouds, called coronal mass ejections (CMEs). These solar storms have been known to have damaging effects to Earth, satellites, and spacecrafts that get in its way.
"This image was taken on May 28, 2015, in combined wavelengths of extreme ultraviolet light by NASA's Solar Dynamics Observatory, which observes the sun 24 hours a day," NASA's Goddard Space Flight Center stated.