Dave Markel wrote that – while aurora chasing – he captured this proton arc near Kamloops, British Columbia, Canada, on September 28, 2016. This photo is a five-image composite of the event.
Thank you, Dave!
A proton arc is indeed rare. Although many experts say they’re caused by protons from the sun (giving them their name), other experts disagree. You can read more about what might, or might not, cause proton arcs at Spaceweather.com.
Bottom line: Proton arc over Kamloops, British Columbia, Canada in September 2016.
Deborah Byrd created the EarthSky radio series in 1991 and EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.