From what's been said recently, the red bits aren't conventional aurora, but "STEVE" ( Strong Thermal Emission Velocity Enhancement - https://www.bbc.co.uk/weather/articles/c4g0j7zn813o) - seemingly due to ions (from the sun?) rather than gases in the atmosphere.

   - Andy.

The effect called STEVE is not to do with climate change and has far more to do with Solar flares and the incident levels of X-rays, its not that unusual - we are in a more active solar cycle than the last few, so it may be that folk have forgotten what it was like. Certainly many radio folk seem to have. Trustworthy observation reports  of similar phenomena date back to at least 1700s though there are far earlier unscientific reports that could be this or something else. It is likely to have happened for the life of the earths atmosphere.

And Smartphone cameras which pull up the coloration in a way the naked eye cannot, were not  a thing in previous cycles so very few folk outside perhaps university physics depts, had the kit to take those sort of pictures.

The colours are the ionization spectra of atoms in the upper atmospheric gasses, but the energy to ionise them is solar in origin.

Mike

The effect called STEVE is not to do with climate change and has far more to do with Solar flares and the incident levels of X-rays, its not that unusual - we are in a more active solar cycle than the last few, so it may be that folk have forgotten what it was like. Certainly many radio folk seem to have. Trustworthy observation reports  of similar phenomena date back to at least 1700s though there are far earlier unscientific reports that could be this or something else. It is likely to have happened for the life of the earths atmosphere.

And Smartphone cameras which pull up the coloration in a way the naked eye cannot, were not  a thing in previous cycles so very few folk outside perhaps university physics depts, had the kit to take those sort of pictures.

The colours are the ionization spectra of atoms in the upper atmospheric gasses, but the energy to ionise them is solar in origin.

Mike