3rd Order Rainbow! ~ The rainbow fragment at left looks like an ordinary bow - much too wide though. It isn't. The camera is looking towards the sun which is hidden by cloud. This is the long sought 3rd order bow first captured in May, 2011 by Michael Gro▀mann. Here Michael has done it again. He imaged this bow on 29th June '14. The picture is a composite where the bow has been unsharp masked to enhance its visibility. It looks an 'easy' picture to obtain - far from it, it took great experience and perseverence.   All images ©Michael Gro▀mann, shown with permission
The familiar primary rainbow is formed by rays reflected once inside raindrops. The outer secondary bow from two reflections. Both are opposite the sun.

The tertiary bow is instead centred on the sun itself. It is broad, faint and very hard to see in the glow of rays that pass through raindrops without reflection not to mention the glare of the sun itself.

Rays of higher and higher order bows enter raindrops closer and closer to the rim and at grazing angles. The colours are dispersed more strongly and the higher order bows get wider and wider.

Looking in the opposite direction - away from the sun - Michael Großmann has captured the "ordinary" primary and secondary bows.

The shadow of his camera is at the bows' centre.

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