A spectacular solar flare erupted early this morning. But instead of escaping out into space, billions of tons of charged plasma fell back onto the surface of the sun in a coronal rain shower.

“I’ve never seen anything like it before,” said NASA solar physicist Jack Ireland.

The event began at about 2:30 a.m. Eastern time and continued for several hours. The flare itself — the brief bright flash at the beginning of the video above — was fairly ordinary and medium-sized. But the loop of magnetized plasma ejected by the flare, called a filament, was at least as large as 10 Earths.

Filaments that...