Angel,
You hear them on the radio. The Aurora reflects radio signals and I have heard vhf from Russia coming in (at ground level) in S.England. The signal has a very distinctive "growling" sound.
Radio "hams" use this method of anomalous propogation (and many others!) to make contacts over "theoretically impossible" distances.
(G8ILJ)
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What goes around . . .
. . often lands better!