Thursday, May 30, 2013

Please Explain This

Update: As William Connolley points out in the comments, these are a phenomena known as "ice spikes." More here and here.
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Please, someone explain this to me: for the second time in a month, there is a strange growth on my ice cubes:


It's a near-verticle sliver extending upwards. I filled the ice cube tray with water (cold water, I think), and put it in the freezer about 2-3 hours ago. I happened to look in and found this, which is similar to one I saw a month ago, though that one wasn't as long.

Here's another view:


The only thing above the tray are some frozen pieces of chicken wrapped in aluminum foil -- well frozen, since I put them in about two days ago. I don't see any drips from them.


As you can see, there is another, smaller growth in the front left of the tray:


What the heck is going on?

5 comments:

Mike said...

Wild guess - the surface of the cells is freezing first and as the inside of the cell freezes it expands. For some reason there is only one opening and it builds up there.

Never see this myself.

Oale said...

Is that repeatable? The aluminium foil above might consentrate the thermal radiation from the freezing process back to that one spot. I've seen some bumps in ice cubes but nothing that big.

David Appell said...

It's not very repeatable -- it happened once about a month ago, but doesn't usually happen.

I should take out the foil packages, just to be sure, and keep filling and refilling the ice cube trays to see if I can get it to happen again.

William Connolley said...

Its a known thing, though as you say, rare. There's a wiki page :-)

http://en.wikipedia.org/wiki/Ice_spike

or

http://www.its.caltech.edu/~atomic/snowcrystals/icespikes/icespikes.htm

David Appell said...

Aha! Thanks William....