Eclipse Mirage

Eclipse with a Difference

An image by Jeremy Kirkendall of the November 3rd 2013 partial solar eclipse. Taken at Point Lookout State Park in Maryland as as the eclipsed sun rose over Chesapeake Bay.

The two bright areas at the false horizon are part of an inverted miraged image. Look at the line of clouds. They are miraged too and apparently mirrored about a line above the sea - the mirage 'vanishing line'.

The choppy upper level of the sea is not the horizon, it is the lower edge of the mirage.

©Jeremy Kirkenall, shown with permission

Left: An equivalent miraged uneclipsed sun and its time sequence (a sunset) captured a few years ago by Michael Myers.

The sun takes on an omega or 'Etruscan vase' shape. The lower image is an inverted sun.

Right: The enlarged picture by Jeremy Kirkendall shows the moon shadowed area inverted close to the sea.

A layer of warm air beneath cooler air produced the eclipse mirage. Probably the air had been warmed overnight by contact with the relatively warmer ocean.

Light rays passing from the upper cooler air across the temperature gradients into the lower warm air are refracted towards the cool layer. In cases where the refraction is strong enough the ray is deflected so that it travels upwards - In that event the eye perceives the upward going ray as coming from a reflected object (the sun or a distant cloud) beneath the real one.

At right, rays leaving a cloud at point (a) can reach the eye via two routes. The lower strongly refracted rays helps form an inverted image. Point (b) behaves the same. Only one ray reaches the eye from point (c) and rays from lower down cannot reach the eye at all. Point (c) marks the position of the mirage 'vanishing line'. The vanishing line bisects the clouds in the eclipse picture at top.