Holey Sun Could Fire Up Auroras Tonight

The full moon rises from the Wisconsin shoreline of Lake Superior as colorful trees near Duluth’s Hawk Ridge are still aglow in twilight last week. Credit: Bob King

In one of the Winnie the Pooh stories I read to my kids, the lovable bear carries around a bag or sock with a hole in it. One day, he and Piglet get lost in the forest, but thanks to the the hole, the crumbs lead them back to safety. The sun’s like that. It has holes called coronal holes, where its magnetic fields are unbound and unfurl into space, carrying with them “crumbs” of electrons and protons that can stimulate auroras back here on Earth.

A creepy, pumpkin-faced coronal hole takes aim at the Earth earlier this week on Oct. 9. Credit: NASA/SDO

A nice, big coronal aimed in our direction is expected to do just that this early evening when space weather forecasters are expected a G1 minor geomagnetic storm. G1 usually means that the northern U.S. and Canada could get a modest northern lights show, so be on the lookout tonight. I’ll keep watch from my outpost near Duluth, Minn. and report back with photos later this evening should the lights materialize.

Tonight’s the night that 2012 TC4, a bus-sized, potentially hazardous asteroid, flies by Earth. It won’t be getting close enough to worry about despite what you may hear. See my earlier blog for more information.