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STEVE glows pink. Photo: Ryan Sault/AGU

The Internet's favorite light in the night sky finally has an origin story.

What's new: Scientists have figured out what causes the cosmic phenomenon affectionately known as STEVE — a mauve-colored streak that appears farther south than where auroras typically are visible.

Details: A new study published in the journal Geophysical Research Letters suggests that STEVE — short for Strong Thermal Emission Velocity Enhancement — isn't an aurora at all, but is in fact a "skyglow" created by heated and shining particles in the ionosphere.

  • STEVE's glow is produced when particles in the ionosphere are heated through friction, causing them to glow, according to a news release accompanying the study from the American Geophysical Union.
  • Auroras, on the other hand, are caused by charged particles from the sun slamming into neutral particles in the upper atmosphere, creating their distinctive glow.
  • The study drew on satellite data collected when STEVE was aglow in April 2008 and May 2016, and then matched them against photos of the phenomenon.
  • A 2018 study showed that STEVE wasn't an aurora, but it was still unclear exactly what caused the glow.

Background: STEVE rose to prominence in 2018, when news of the new kind of skyglow with the funny name spread on the internet. The unique glow was first noted by a sky-watchers' Facebook group, with one of the members, Chris Ratzlaff, naming it STEVE, according to NASA. It wasn't until later on that STEVE received its acronym.

Go deeper

Hill votes will make global waves

President Biden addresses the UN General Assembly on Sept. 21, 2021 in New York City. Photo: Eduardo Munoz-Pool/Getty Images)

This epic week for President Biden on Capitol Hill is even bigger than his domestic agenda.

Why it matters: Biden has anchored his entire strategy for foreign affairs on the notion that "America is back." What that means in practice is that Biden needs to prove democracy works to rally America’s liberal allies against rising authoritarians.

54 mins ago - World

German election: Exit polls show close race to succeed Angela Merkel

SPD leader Olaf Scholz. Photo: Alex Kraus/Bloomberg via Getty Images

BERLIN — The first exit poll from Sunday's German elections showed the center-left Social Democrats (SPD) and the center-right Christian Democrats (CDU) in a dead heat at 25%, leaving the race to succeed Angela Merkel too close to call.

The state of play: A second exit poll showed the SPD narrowly ahead. That's the one televisions displayed at SPD headquarters in Berlin, where the room erupted into cheers. Official results will roll in throughout the evening.

Abbott says he'll hire Border Patrol agents who whipped at migrants

Texas Gov. Greg Abbott (R) on Sunday defended the actions of U.S. Border Patrol agents who charged at Haitian migrants on horseback, blaming the Biden administration for not preventing them from crossing the border.

Why it matters: Abbott's remark on "Fox News Sunday" comes amid increased backlash over the incident, with President Biden saying, "I promise... those people will pay,” and the Department of Homeland Security launching an investigation.