Sun Has Many Campfires that Are Micro and Nano Solar Flares

The Solar Orbiter flew within 48 million miles of the Sun and took the closest pictures of the Sun to date. Other spacecraft have been closer, but none have carried Sun-facing imagers.

Solar Orbiter carries six imaging instruments, each of which studies a different aspect of the Sun. Normally, the first images from a spacecraft confirm the instruments are working; scientists don’t expect new discoveries from them. But the Extreme Ultraviolet Imager, or EUI, on Solar Orbiter returned data hinting at solar features never observed in such detail.

Principal investigator David Berghmans, an astrophysicist at the Royal Observatory of Belgium in Brussels, points out what he calls “campfires” dotting the Sun in EUI’s images.

“The campfires we are talking about here are the little nephews of solar flares, at least a million, perhaps a billion times smaller,” Berghmans said. “When looking at the new high-resolution EUI images, they are literally everywhere we look.”

It’s possible they are mini-explosions known as nanoflares – tiny but ubiquitous sparks theorized to help heat the Sun’s outer atmosphere, or corona, to its temperature 300 times hotter than the solar surface.

Written By Brian Wang,