Believe it or not the ISS was over the North/South Carolina state line when a crew member captured this shot of the Northern Lights on August 3, 2016. That’s Lake Erie on the US/Canada border in the foreground, flanked by Detroit to the left, Toronto to the right, and Cleveland at bottom center. The Auroral display itself is several hundred miles further north. A good telephoto lens at an altitude of 250 miles can really shrink the world.
Aurora are the result of the interaction between charged particles borne by the solar wind, Earth’s magnetosphere, and the various gases in our atmosphere.
This image clearly shows two of the many shapes aurora can assume. Above the vivid blue of the lower atmosphere we see the most common manifestation - a distinct green oval, centered around the north magnetic pole. Even when viewing it edge-on the oval shape is still discernible. Depending on the intensity of the solar storm this oval may extend well southward into the continental US.
The other common shape visible here is the violet curtain of vertical rays extending into the highest reaches of the atmosphere.
If the colors remind you of neon lights, that’s because the process of electrically exciting a gas to generate light is pretty much the same in beer signs and aurora.