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Mock-Mirage Sunset, Hungary ~ An image series by Rafael Schmall from the new star sky park, Zselici Csillagpark. As the sun sinks its rays enter a strong temperature inversion. The rays curve as they are refracted between air layers at different temperatures. Several ray paths reach the eye yielding multiple sun-slice images. Some are inverted and ascend while others are upright and descend. This is the stuff of green flashes and one is visible in the 2nd row and large image below.    Images ©Rafael Schmall, shown with permission
Nearby balloon measurements provided this profile. Normally, air nearest the ground is warmest and gets colder with height. Here there is a very strong temperature inversion up to 700m.

Multiple images signal fine temperature structure in atmospheric layers.

Now the mirage simplifies to a lower descending (upright) image of the sun's upper limb and above it an ascending inverted image of the same.

A mock-mirage green flash briefly adorns the sun's upper limb.

Unlike inferior mirage flashes, these are not visible to the unaided eye.

Never be tempted to view through binoculars. The sun might be visibly dim but copious amounts of infra-red are still being transmitted.