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Mirages, Mirages

A tranquil scene. Car parked, perhaps for a picnic, near a cooling river or lake. We see its reflection where the water is smooth.

Not so. There is no cooling water. It is Death Valley National Park, California imaged by Steve Mattan. The camera looks across hot and dry land.

The 'reflections' are an inferior mirage. Inferior because they are below the car.

The 'reflections' bear closer inspection.

Images ©Steve Mattan, shown with permission
Multiple car images by Jari Luomanen.

An almost ideal mirage is below. Oil storage tanks are miraged and we can tell the image orientations from the slope of the access steps. Inverted, erect,inverted and so on.

Even here, some images compress, others stretch.

Image by Mark Evans.

Inverted and erect images alternate

Steve Mattan's mirage has three or four images. The first is maybe upright rather than inverted. It's hard to tell the orientation of the lower ones.

No rules are being broken. Depending on the nuances of the air temperature gradients, some images can be squashed into lines. Others are vertically stretched. Turbulent air might mask some as wind rippled 'water'.

Inferior mirages, hot road or desert oasis mirages form by light refracted between lower hot air and upper cool air. We traditionally regard them as a single mirror 'reflection' apparently in bright water. The mirrored object is upside down. The 'water' is not thirst quenching. It is miraged sky.

That is only part of their story.

A more complete inferior mirage has many images. The first is inverted. Below is an erect image. Then another inverted one. And so on. Strict topology rules dictate what images can form and in what order.