Does the author ever explain or mention again the sudden red sky they saw in paragraph 3? Puzzling, doesn't sound like aurora; if the date was known it might be easily confirmed or corroborated. Not sure why it was even mentioned...
> Finally, they decided it had to be the northern lights, visible from unusually far south.
This is from that same paragraph. Personally, I'm not convinced of that. Lightning behind a cloud could have done it, and would be more plausible from my perspective.
Otherwise, if it was just after sunset, perhaps it was a false sunset(say behind a massive dark cloud) and then when the sun fell below the cloud, you get the amazing red sunset(s) that are common in the desert.
