Arches of magnetic field lines towered over the sun’s edge as a pair of active regions began to rotate into view in this video captured by NASA’s Solar Dynamics Observatory on April 5-6, 2016.
Active regions are areas of very concentrated magnetic field. Charged particles spiraling along these magnetic fields emit extreme ultraviolet light, which is typically not visible to our eyes, but colorized here in gold. The light given off from the particles helps trace out the magnetic field lines, which are otherwise invisible.
Scientists use images such as this to observe how magnetic fields move around the sun and learn more about what causes active regions.
