STEVE

A STEVE over Little Bow Resort, Alberta, in August 2015
A STEVE over Crossfield, Alberta, in March 2018 (around 12:30 a.m.)

STEVE (backronym for Strong Thermal Emission Velocity Enhancement) is an atmospheric optical phenomenon that appears as a purple and green light ribbon in the night sky, named in late 2016 by aurora watchers from Alberta, Canada. According to analysis of satellite data from the European Space Agency's Swarm mission, the phenomenon is caused by a 25 km (16 mi) wide ribbon of hot plasma at an altitude of 450 km (280 mi), with a temperature of 3,000 °C (3,270 K; 5,430 °F) and flowing at a speed of 6 km/s (3.7 mi/s) (compared to 10 m/s (33 ft/s) outside the ribbon). The phenomenon is not rare, but had not been investigated and described scientifically prior to that time.[1][2][3]

  1. ^ McRae, Mike (24 April 2017). "Introducing Steve - a Newly Discovered Astronomical Phenomenon". ScienceAlert.
  2. ^ "When Swarm Met Steve". esa.int. European Space Agency. 21 April 2017.
  3. ^ "New kind of aurora is not an aurora at all". American Geophysical Union. 20 August 2018. Retrieved 2018-08-21 – via Phys.org.