While CME's and solar flares tend to disturb and even black out some of HF in some bands, HIGH AURORA will enhance VHF signals, but make them sound watery and "disembodied".
This is the main reason on VHF for Aurora Mode as well as EME (communicating by bouncing a signal off the moon both ways; earth - moon - earth) morse code/CW is used.
Technology from the early 1800's still tops the list. For now.
