One of the first science fiction books I ever owned was Vonnegut’s Cat’s Cradle—what a way to start reading SF! The only thing I really remember from it today is, of course, ice nine. My generation of nerds was ready for the materials revolution, that’s for sure! (We also didn’t need Malthus explained to us, because we all watched The Trouble With Tribbles. But that’s another story.)
In the past fifty years, scientists have been able to make 20 forms of crystalline ice. There are also two “amorphous”, non-crystalline forms of ice—essentially water glass. I gather that there is also a form of H2O that is both solid and liquid. Who knew?
This winter researchers at UCL discovered yet a third form of amorphous ice, with the same density as liquid water [2].
They were seeking to study very tiny crystals of ice, which they intended to create by ball milling. I.e., steel ball bearings were put in a really cold container of ice and shaken 20 times per second.
Instead of very fine snow, they got—medium density amorphous ice. (Which, by the way, kind of explodes when you compress and then release it. Not exactly your grandfather’s ice.)
Which was, to quote one of the researchers, “completely unexpected and very surprising,” ( Prof. Christoph Salzmann, quoted in [1]). And also “really cool” ( Marius Millot, quoted in [1])
No kidding!
This new form and the other exotic ices (and solid-liquid) generally can’t exist on the surface of the Earth. They exist in deep cold and / or high pressures, and just melt into plain water. So no Cat’s Cradle scenario with these.
But some of these, especially the amorphous forms might exist in space. Like say, on an icy moon with lots of tidal forces. It’s something to look for.
I’m not sure how you would detect amorphous ice from orbit or flyby. I’m sure the elves of ESA and NASA are working on it.
I’m also not sure what either the presence or absence of amorphous ice will tell us. Finding amorphous ice would, I think, tell us that some pretty specific conditions must exist to generate the ice and for it to last long enough to be observed. But that’s as far as I know.
I gather that the UCL researchers are thinking about further experiments incorporating impurities. At this point, I’m prepared that pretty much anything might happen. So, it will be interesting to see what does happen.
- Kenneth Chang, Shaking Ordinary Ice (Very Hard) Transformed It Into Something Never Seen Before, in New York Times. 2023: New York. https://www.nytimes.com/2023/02/03/science/new-ice-glass.html
- Alexander Rosu-Finsen, Michael B. Davies, Alfred Amon, Han Wu, Andrea Sella, Angelos Michaelides, and Christoph G. Salzmann, Medium-density amorphous ice. Science, 379 (6631):474-478, 2023/02/03 2023. https://doi.org/10.1126/science.abq2105
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