Scientists have already confirmed in 2018 that the sky-glow named “STEVE” is in fact not an aurora, but now, we have available a new study in which the researchers explain the mechanisms that determine it.
The sky-glow captured the attention of many people when it came into view like an aurora in an area which is farther from south that where auroras normally appear. The phenomenon had also lavender shades rather than the ordinary green of the auroras. What is even curious is that to the mauve shades, “picket fence” of green vertical lights are sometimes added.
The new sky-glow was labeled as strong thermal emission velocity enhancement (STEVE) and scientists confirmed soon after that STEVE is actually not an aurora, and this because auroras are created when glowing nitrogen and oxygen atoms on the Earth’s superior atmosphere are triggered by the charged particles from the planet’s magnetosphere. By year 2018, researchers already knew that the mechanism that causes STEVE is not the same. Even though, they didn’t know what causes STEVE, and so they simply labeled it as a “sky glow”.
Researchers of a new study released in the Geophysical Research Letters inspected satellite data and ground images of STEVE, and deduced that there are two separate mechanisms that are causing STEVE’s lavender light arc and green picket fence.
The green “picket fence” is in fact caused by the same mechanism that conceives auroras, but it is still uncommon in the fact that is appears in areas where auroras do not normally emerge. Scientists have also noticed that the picket fence is developed when high-frequency waves from the magnetosphere excite electrons and destroy them out of the magnetosphere thus designing the striped image.
The reddish arc it occurs in a similar way that incandescent light bulbs work, researchers explained. When a flow of charged particles in the Earth’s ionosphere crash, it creates friction, heating the particles and birthing the russet arc.
Except for their discoveries, researchers also point out the importance of data they collected from citizen scientists, and NASA even actually asked citizen scientists for help in sighting STEVE.