Scientists from the Center of space flights of Goddard in the US found out the cause of a rare species of polar auroras, called “Steve”. Unusual glow, which was first seen in 2015 appears due to a supersonic flow of ions in the ionosphere of the Earth. This was reported in an article published in the journal Science Advances.
“Steve” was first spotted by enthusiasts from the organization by the Alberta Aurora Chasers who are engaged in observations of the Aurora. They found a relatively narrow ribbon of green and purple light, differing from other known species of the Aurora Borealis. This atmospheric phenomenon may be hundreds or thousands of kilometers, and the width of the “ribbon” is 25-30 miles.
Scientists call the lights “powerful speed increased thermal emission” (Strong Thermal Emission Velocity Enhancement, STEVE). They pointed out that “Steve” associated with SAID — sub-auroral ion drift. It is a narrow stream of charged particles that occur on the night side of the planet or near the terminator — the line of sotrasel.
It was considered that the ion drift does not emit radiation, but the new data show that the unusual Aurora Borealis is a manifestation of SAID. During the simulation, it was demonstrated that the ion drift can emit red radiation, but the mechanism of green and purple colors yet unknown.
Video, photo All from Russia.