Question about "northern lights"

If you flew up into them, would the plane cause them to break up?

Yes... except that they are so far up that planes (in general) cannot get that high.

Charged particles travelling in bunches (or streams) at high speed is exactly the same as an electrical current... without a wire.

The air, at that height, is so thin that it is like the inside of a neon tube.

The charge, going through the air, will rip electrons away for the air molecules. The molecules will regain an electron relatively easily, and when the electron "falls back" into place around the molecule (or atom), it emits a photon, representing the energy lost as it "falls back" into place. This is the same energy as what was used by the charged particle to rip it our of position in the first place.

That is why different gases show different colors (orbits have different energy levels around different atoms and molecules).

Thus, the northern lights and neon tubes work the same way... except the Northern lights have no tube and no wires (the air is already at the correct pressure and the charged particles are already travelling fast enough, channelled by the Earth's magnetic field).

The northern lights occur in the upper atmosphere about 50 miles above sea level. Airplanes don't fly at that altitude.

no
but it could mess with the compass and electronics

I don't think so.