Strange Light Phenomenon Nicknamed 'STEVE' Delights Onlookers: 'Amazing'

A bizarre streak of light across the night sky nicknamed "STEVE" appeared on Sunday night, during the heights of the geomagnetic storm.

STEVE, which stands for Strong Thermal Emission Velocity Enhancement, was spotted as a column of pinkish-red light stretching across the New Zealand sky, with many astrophotographers sharing pictures of the strangely-named phenomenon to social media.

The severe G4 geomagnetic storm also led to the northern and southern lights casting a spectacular glow across the globe, with the northern lights stretching as far south as California.

One photographer named Ian Griffin uploaded a photo and a video of STEVE to Instagram, taken from the Otago Peninsula in New Zealand.

"STEVE visits the Otago Peninsula in this timelapse I shot last night," he captioned his video. "Last night at around 9:30 p.m. [local time], aurora chasers across the Otago Peninsula (who weren't blinded by the constant flow of traffic with full beam headlights) got to see a beautiful pinky white beam running across the sky from east to west."

Griffin also uploaded his picture to spaceweather.com's Realtime Image Gallery, with the caption: "The night was amazing, with a wonderful display of the Aurora Australis dominating the southern sky. At around 9:30pm local time, an unexpected guest arrived! STEVE made a brief appearance high in the Western sky."

While the STEVE phenomenon also occurs during geomagnetic storms, it's not actually an aurora, and is instead caused by is caused by a ribbon of hot gases in the atmosphere.

Unlike the northern and southern lights, which are a result of solar particles like protons and electrons interacting with our atmosphere, STEVE is caused by ribbons of exceedingly hot (5,400 degrees Fahrenheit) gases flowing through the atmosphere at 13,000 miles per hour, according to the National Oceanic and Atmospheric Administration.

These ribbons appear during strong geomagnetic storms and were first identified as a separate phenomenon from auroras in 2016 by Canadian citizen scientists.

A study in the journal Geophysical Research Letters, published in 2019, found that STEVE is caused by a flow of hot, charged plasma particles colliding in Earth's ionosphere. These rivers of particles create friction, heating up the plasma, resulting in the emission of STEVE's characteristic mauve-pink glow.

Occasionally, STEVE appears in the form of a "picket fence" pattern, forming several parallel green stripes. This phenomenon, which is also seen to occur simultaneously in both the northern and southern hemispheres, is thought to be driven by something called "energetic particle precipitation."

This is caused by high-frequency waves moving from Earth's magnetosphere to its ionosphere and energizing electrons, creating eddies in the flow like a rippling river. However, the exact mechanism behind the picket fence's formation is still unclear.

Other photographers around New Zealand also spotted STEVE hanging in the sky, with one Twitter user, @five15design, posting a photo of the phenomena with the simple caption: "STEVE??"

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