Bok
11-18-2017, 11:58 AM
NASA's Solar Dynamics Observatory came across an oddity that the spacecraft has rarely observed before: a dark filament encircling an active region (Oct. 29-31, 2017). Solar filaments are clouds of charged particles that float above the sun, tethered to it by magnetic forces.
More... (http://www.nasa.gov/image-feature/rare-encircling-filament)
More... (http://www.nasa.gov/image-feature/rare-encircling-filament)