Steve and a picket fence taken looking south over Berg Lake and Mount Robson. What is Steve? Most have never heard of it, those that have might just think it's an Aurora. Let me explain below why this purple ribbon is so special and why this shot is so important.
This extremely rare capture went viral, and became a piece of scientific history. The shot and associated time-lapse were then used in the physics paper led by W. E. Archer, “The Vertical Distribution of the Optical Emissions of a Steve and Picket Fence Event” published in Geophysical Research Letters, of which I was a co-author. The paper advanced our understanding of these phenomena by narrowing down the altitude extent of the Steve and picket fence emissions.
Steve is east/west mid latitude phenomena at lower latitudes than you typically see an Aurora. The phenomenon is thought to be caused by a 25 km (16 mi) wide ribbon of hot plasma at 3000C (5430F) flowing at a speed of 6 km/s (3.7 mi/s) (compared to 10 m/s (33 ft/s) outside the ribbon).
While occurring with the same space weather that brings an Aurora; Steve is not an aurora as it is not generated through the precipitation of electrons. Steve runs East/West while an Auroral beams runs North/South along the magnetitic field lines to the poles.
For unknown reasons Steve is sometimes but not always associated with a picket fence aurora. The picket fence always forms below Steve and is thought to be caused by electron precipitation. While Steve has been witnessed and documented by the aurora chasing community for a long time it is only newly being characterised by the science community.
The paper advanced our understanding of these phenomena by narrowing down the altitude extent of the Steve and picket fence emissions.
I was fortunate enough to capture Steve while observing to the South while at Berg Lake. This meant I was clear of any interference from the Aurora to the North. The image was taken while camping overnight at 1,646m (5,400 ft) as part of a multi-day back country hike.
The North Face of Mt Robson rises 2,308m (7,572ft) out of the lake to a total height of 3,954 m (12,972 ft) and is the highest peak in the Canadian Rockies.
