User Comments
It was an exceptionally still day, as we ascended went through a cloud layer only about 10m thick and saw Brocken spectre - a very geeky day.
https://en.wikipedia.org/wiki/Fata_Morgana_(mirage)
elsewhere - 10/Dec/17
https://en.wikipedia.org/wiki/Fata_Morgana_(mirage)
https://www.atoptics.co.uk/opa_mir.htm