Canadian Amateur Astronomer Discovers A Mysterious Aurora Named Steve

SALIK KHAN | 0
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| March 18 , 2018 , 15:08 IST

On the night of July 25, 2016, amateur astronomer and avid skywatcher Bourassa, an IT technician in Regina, Canada was out with his two kids to show them the colorful dance of the moving light in the night sky- Aurora Borealis. Around midnight, he noticed a thin purple ribbon of light appeared in the sky which started glowing, he immediately clicked some pictures and videos of the mysterious light.

 

Having spent years in chasing Auroras, he knew that purple ribbon of light is not the usual Aurora, it was something else. This accidental observation has contributed to the discovery of a new type of the Aurora, unrecognised until now. Bourassa along with the other member of a Facebook group called Alberta Aurora Chasers gave this mysterious light, a new name, Steve.

But these amateur astronomers still didn't know what it was.

STEVE and the Milky Way at Childs Lake, Manitoba, Canada. Credit: Courtesy of Krista Trinder

A citizen science project called Aurorasaurus funded by NASA tracks the aurora borealis through user-submitted reports and tweets by people like who are excited about a science field but don't necessarily have a formal educational background published their findings in a recently published report. After analyzing the user-submitted images and then corresponding satellite data, NASA learned that Steve is not a normal aurora.

"Steve is the visible counterpart to a feature in the upper atmosphere called a subauroral ion drift (SAID),” says Elizabeth Macdonald, a geo- and heliophysicist at Nasa explaining why Steve is different from standard Aurora. The study further says that “this narrow, subauroral, visible structure, distinct from the traditional auroral oval, was largely undocumented in the scientific literature and little was known about its formation.”

SAIDs appear in areas closer to the equator (like southern Canada) as opposed to where most auroras appear. Until now, we had no idea that SAIDs had a visual component, but the discovery of Steve changes everything.

Auroras occur when a stream of charged electrons and protons flowing from the Sun – interacts with the Earth's magnetic field, generating strong electrical currents. Even though the process of creation of the aurora and Steve starts with the Sun bombarding charged particles toward Earth, but Steve travels along different magnetic field lines than the Aurora, towards the lower altitudes.

Steve’s discovery is important because of its location in the sub-auroral zone, an area of lower latitude than where most auroras appear. This also means the charged particles that create Steve connect to magnetic field lines that are closer to Earth's equator, hence why Steve is often seen in southern Canada.

Studying Steve will help us in understanding Earth’s upper atmosphere can have visible and noticeable effects in the lower part of Earth’s atmosphere. “This provides good insight on how Earth's system works as a whole,” said MacDonald. An accidental observation of an amateur astronomer is now helping us to understand how Earth’s magnetic field interacts with charged particles at different altitudes. "It is my hope that with our timely reporting of sightings, researchers can study the data so we can together unravel the mystery of Steve's origin, creation, physics and sporadic nature," said Bourassa. "This is exciting because the more I learn about it, the more questions I have,” he added.

To keep its initial name and to pay a homage to its original discoverers, Steve’s technical name is “Strong Thermal Emission Velocity Enhancement”, or in other words, STEVE.

Salik Khan is the Head of Social Media Communications (Ghalib-in-Chief) at Talk Journalism. He talks about poetry, Physics and Ghalib on Instagram and Twitter at @baawraman