Who would have ever thought something named Steve could be so mysterious? Last year, astronomers studying crowdsourced images of auroras noticed that many aurora photographs seemed to also show an eerie purple glow in the skies which seemed to be its own phenomenon separate from the classic northern lights. After poring over thousands of images, University of Calgary’s Eric Donovan finally gave this mysterious phenomenon a name: Strong Thermal Emission Velocity Enhancement, or Steve.
Initially, it was believed that Steve was merely a part of the northern lights given that Steve seemed to coincide with this well-studied atmospheric event. However, after studying Steve for over a year now, scientists believe Steve is not an aurora after all, but its own unique and unexplained phenomenon.
According to researchers from the University of Calgary and the University of California, Los Angeles, Steve is his own from of “sky glow” since Steve does not contain the typical charged particles which constitute auroras. "Our main conclusion is that STEVE is not an aurora," University of Calgary space physicist Bea Gallardo-Lacourt said in a press release. "So right now, we know very little about it. And that's the cool thing because this has been known by photographers for decades. But for the scientists, it’s completely unknown."
In a study published earlier this year, scientists found that Steve appears to be caused by fast-moving ions and super-hot electrons passing through the ionosphere. However, the most recent study published this week claims that Steve “might not be associated with particle precipitation” at all but instead may be generated from within the ionosphere itself by “a process unknown by the authors that could produce electron precipitation.” Who knows what further study of Steve might reveal?
Studies like this one give me hope that we actually know next to nothing about this Earth we think we know well. We’ve only had the capability to send scientific instruments and aircraft into the skies or deep under the water for a century or so. Just imagine what tomorrow’s science will reveal.