On September 1st, 2019 I crept outside into the dark night of Alaska to meet STEVE and it and I had a photo shoot together. It had been awhile! But usually once a year we have a chance to get a look at a each other. I’m not talking about my cousin Steve, in fact, STEVE is not a person at all. STEVE stands for Strong Thermal Emission Velocity Enhancement.
The last time I wrote about STEVE it was to dispel the mis-classification of these images online as “Proton Arcs”. At that time scientists were grappling with what caused this mysterious form of the aurora. There was uncertainty on why it showed up white instead of green and what form of energy would cause the aurora at all. Although it has likely been observed by sky watchers since the point where humans could comprehend its beauty it was relatively new to science and only really entered the literature in 2016.
Strong Thermal Emission Velocity Enhancement
” Strong Thermal Emission Velocity Enhancement ” – that’s quite a load of Jargon! However, once you understand how these auroras form it makes mores sense.
Typical auroras are formed when energy from the sun collides with nitrogen and oxygen in our atmosphere. The collision results in green or red light being let off. However, based on recent science published on Space.com STEVE forms when charged particles are super-heated outside of the “auroral zone”. The particles emit the white and pink light we see on the ground.
If you are still a bit unclear remember that light occurs as a physical process – it’s the release of energy. For instance when you heat an electric cooking stove the orange light emitted is the release of energy. STEVE is a bit like a monstrous electric coil in the sky!
A Gallery of STEVE
I think my latitude in Southeast Alaska is a hotspot for STEVE. I have observed it 5 times to date since 2016. I recently added my photos to a database of STEVE observations. The images below are from the same night as the images above. You can see a short timelapse of STEVE that night by going to a video on my Facebook page.
The Rest of the Show
STEVE shows up on the biggest nights of aurora. It definitely seems to be linked to high amounts of energy coming in. During the nights and mornings of August 30 – September 1st the Aurora was visible almost anytime it was dark.
On the second night of the show I focused less on photography. My wife and I curled up on a blanket on the beach and watched the lights dance overhead. We had some pretty amazing coronas for Southeast Alaska!
I’ll be keeping an eye out for any further science and revelations on STEVE. I hope to see it again!