top of page

Meet Steve, the mysterious sub-auroral phenomenon

Photographers have been taking pictures of a phenomenon that was until recently unknown to scientist.

Elizabeth MacDonald (NASA scientist and PI of the great initiative called Aurorasaurus: was working for quiet some time with a group of very talented sky watchers citizen scientist called the "Alberta Aurora Chasers" (Facebook group).

MacDonald came last year to the University of Calgary (UCalgary) to give a colloquium in the Department of Physics and Astronomy with the presence of the Alberta Aurora Chasers and UCalgary Scientists, included Eric Donovan. After her talk the Chasers started mentioning about a phenomenon they have photographed and called "the proton arc". Donovan, knowing that the proton aurora is not visual asked them to see some pictures. The chasers started showing beautiful pictures of a very narrow arc, that appear to be a very low latitudes to be an auroral arc. Since according to the above mentiones, this wasn't a proton arc, Donovan suggested to change the name, Chris Ratzlaff proposed the name Steve inspired by the movie Over the Hedge, in which a squirrel decides to call Steve to someone they have never seen before. [MacDonald, Donovan et al., in preparation]

Published by Vanexus Photography (

Steve is a very narrow arc at sub-auroral latitudes (below the auroral oval). Satellite data (SWARM, ESA Satellite), shows that Steve is collocated with a very fast ion westward flow , and that these ions are very hot.

The scientific paper is in preparation, but we are looking forward to read it. Meanwhile, below is a video of this beautiful phenomenon.

Captured at 12:12AM CST 25JUL2016, 32km NNE of Regina Saskatchewan Canada.


bottom of page