Caterpillar Tents Dewbow

Imaged near Ofakim, Israel by Amir Bernat, Ilan Ramon youth physics center.

The bow is produced by drops of dew on the 'tents' constructed by woolly bear caterpillars, Ocnogyna loewii.

"The caterpillars live together on the ground using the tent as protection from predators during the day and from the dew at night.

Once they consume the flora under the tent they just move on to create another one.

Whilst they are not poisonous, it is recommended not to touch them as their hairs can irritate the eyes and throat.

Bows from dew drops on spider webs, grass (and woolly bear tents) are usually (but not always) somewhat broader and more pastel hued than rainbows in the sky. Light waves are diffracted more and more as drops get smaller. The colours are increasingly blurred out and the bow radius reduces a little.

Very small drops give the almost colourless fogbow.

©Amir Bernat shown with permission

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