Physic Photo of the Week

Physics Photo of the Week

February 20, 2026  

Bursting Raindrops - photo by Donald Collins

On a winter day in December 2023 I noticed these unusual photos of frozen raindrops on our house deck near Warren Wilson College.  We had a sudden freeze overnight.  The rain had beaded up on the deck boards - probably having been staine in the early summer.  The water and the deck stain repel each other so the surface tension of the water being forced away from the deck stain caused the droplets to bead-up like small spheres with the surface tension forces in equilibrium with the gravitational forces.

However when the water drops froze, the ice formed on the outside parts of the droplets, leaving unfrozen water inside.  As the water within the drops froze, the expansion of water upon freezing exerted pressure on the frozen skin of the raindrops, that the droplet burst, shooting a small jet of water that almost immediately froze.  Practically all the raindrops in the picture exhibit these small bursts.  In cold climates we must take precautions to drain all water pipes and hoses that before leaving them in outdoor environments that will sure burst the pipes.

Physics Photo of the Week will soon exhibit another winter phenomenon of freezing water.  Stay tuned...

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Physics Photo of the Week is published periodically during the academic year on Fridays by Donald F. Collins, professor emeritus of Warren Wilson College. These photos feature interesting phenomena in the world around us.  Students, faculty, and others are invited to submit digital (or film) photographs for publication and explanation. Atmospheric phenomena are especially welcome. Please send any photos to dcollins@warren-wilson.edu.

All photos and discussions are copyright by Donald Collins or by the person credited for the photo and/or discussion.  These photos and discussions may be used for private individual use or educational use.  Any commercial use without written permission of the photoprovider is forbidden.

To join the mailing list, please request to Donald Collins at the e-mail address below.  You will receive no more than one message every two weeks, or when a very interesting physics/astronomy event is happening.

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Comments

  1. Gwen DiehnFebruary 20, 2026 at 3:15 PM

    Thanks, Don! I love the esoteric things I learn from you!

    ReplyDelete

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