[Fred Nerks]

...Instead, it showed something that had never been observed before: a temperature spike of over 5400 degrees Fahrenheit in a spot about 186 miles above Earth’s surface combined with a gas ribbon over 15 miles wide...

And at that distance above the surface of Earth, at just STOPS?

[Swordmaker]

And at that distance above the surface of Earth, at just STOPS?

At the limits of the electromagnetic field that is powering that particular glow discharge or where the conditions that are just right for the glow discharge to occur, yes, it will stop. You can see such filaments in the laboratory and they are self contained and limited by those conditions. While these are artificially generated, they are glow discharge arcs that are constrained by just such conditions. Plasma pressures, electromagnetic fields, etc. constrain where they go and where they stop.