AN OUTBREAK OF MAGNETIC FILAMENTS: The sunspot number may be low, but the sun is far from blank. Amateur astronomers monitoring the sun report a large number of magnetic filaments snaking across the solar disk. Sergio Castillo captured more than half a dozen in this picture he sends from his backyard observatory in Inglewood, California:

“Filaments are popping up all over the solar surface,” says Castillo. “Each one has a unique shape and length.”

The longest one, in the sun’s southern hemisphere stretches, more than 400,000 km from end to end. “It’s one of the longest filamentary structures I have ever seen,” says veteran observer Bob Runyan of Shelton, Nebraska.

If any of the filaments collapses, it could hit the stellar surface and explode, producing a Hyder flare. Filaments can also become unstable and erupt outward, hurling pieces of themselves into space. Either way, astronomers with solar telescopes are encouraged to monitor developments.

fr/spaceweather.com