A long, dark magnetic filament is looping over the sun’s northeastern limb today.
NASA’s Solar Dynamics Observatory took the picture just a few hours ago using the highest-resolution cameras ever flown on a mission to study the sun. Plasma trapped inside the filament is dense and cool relative to the seething inferno below. If the filament collapses, as filaments often do, the plasma could hit the surface and explode, producing a Hyder flare or a coronal mass ejection (CME).