Apr 30, 2019

The origin story behind cosmic phenomenon STEVE

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.

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World coronavirus updates

Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Axios Visuals

Countries where novel coronavirus cases are falling may be hit with a "second peak" if they relax restrictions too soon, World Health Organization emergencies chief Mike Ryan warned during a briefing Monday. "We're still very much in a phase where the disease is actually on the way up," he added.

By the numbers: Almost 5.5 million people have tested positive for the virus as of Monday, and more than 2.2 million have recovered. The U.S. has reported the most cases in the world (over 1.6 million from 14.6 million tests). The U.K. is reporting over 36,900 deaths from the coronavirus — the most fatalities outside the U.S.

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 3 a.m. ET: 5,498,849 — Total deaths: 346,306 — Total recoveries — 2,233,180Map.
  2. U.S.: Total confirmed cases as of 3 a.m. ET: 1,662,768 — Total deaths: 98,223 — Total recoveries: 379,157 — Total tested: 14,604,942Map.
  3. World: Italy reports lowest number of new cases since February — Ireland reports no new coronavirus deaths on Monday for the first time since March 21 — WHO suspends trial of hydroxychloroquine over safety concerns.
  4. 2020: Trump threatens to move Republican convention from North Carolina — Joe Biden makes first public appearance in two months.
  5. Public health: Officials are urging Americans to wear masks over Memorial Day.
  6. Economy: New York stock exchange to reopen its floor on Tuesday — White House economic adviser Kevin Hassett says it's possible the unemployment rate could still be in double digits by November's election — Charities refocus their efforts to fill gaps left by government.
  7. What should I do? Hydroxychloroquine questions answeredTraveling, asthma, dishes, disinfectants and being contagiousMasks, lending books and self-isolatingExercise, laundry, what counts as soap — Pets, moving and personal healthAnswers about the virus from Axios expertsWhat to know about social distancingHow to minimize your risk.
  8. Other resources: CDC on how to avoid the virus, what to do if you get it, the right mask to wear.

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Updated 58 mins ago - Politics & Policy

LATAM Airlines files for U.S. chapter 11 bankruptcy

A LATAM air attendant aboard one of the company's planes in March. Photo: Kike Calvo/Universal Images Group via Getty Images

LATAM Airlines Group SA said in a statement early Tuesday the firm and its affiliates in in the United States, Chile, Peru, Colombia and Ecuador have filed for Chapter 11 bankruptcy protection in the U.S.

Why it matters: Latam is Latin America's largest airline and its shareholders include Delta Air Lines. CEO Roberto Alvo noted in the statement the coronavirus pandemic has had a huge impact on the airline industry.