January 2013

Ice: A Marvelous Matter

Dedicated to Mariana Gosnell, author of "Ice: The Nature, History and the Uses of an Astonishing Substance".
This image depicts ice molecules sticks together.
Frost forming on a window. Image credit snowcrystals.com
Mariana's book "Ice: The Nature, History and the Uses of an Astonishing Substance".
Various snowflakes. Image credit snowcrystals.com

In memory of author Marina Gosnell, who passed away earlier this year, we are running some programs from an interview we did with her a few years ago. Mariana had just written, "Ice: The Nature, the History and the Uses of an Astonishing Substance", a 560-page book celebrating winter's signature ingredient. Winter certainly gets its luster from snow and ice, but aside from its beauty, what makes ice so special?

Perhaps one of the most unique abilities of ice is that it can float in its own liquid - water. Water is actually nine percent lighter as ice than as a liquid. Ice is able to float because of the way the ice crystals are formed. On a molecular level, Oxygen and hydrogen, H20, form tiny hexagons, often in rows and layers so they look like a chicken wire fence. However, in the middle of each hexagon is an empty space, which gives it buoyancy and allows it to float!

Most everyone's favorite form if ice is snow. Did you ever wonder just how it could be that every snowflake is unique, different from all others? It's all in the journey. A snowflake has a long fall through the air. It starts as an ice crystal high in the sky. As is comes down, it picks up vapor and starts to build itself up. It forms arms and branches on from them and begins to take its form. Along the way, the snowflake is constantly encountering varying temperatures and little eddies of air that effect its shape. By the time it makes its way through the atmosphere, a snowflake has been subtly sculpted by all of these influences.

Another familiar form of winter white is frost – sometimes called “snowflakes growing on the ground”. A windowpane can offer the right microenviroment for frost: a cold pane plus moisture in the air, and voila, a line of frost can grow from a little scratch on the glass. It typically follows one direction for a while, but eventually it will branch, because – just like the snowflake - it has slightly different kinds of currents passing over it. It will make wonderful, almost floral, shapes.

If you'd like to learn more about ice, you can find Mariana's book at Barnes and Noble, Biblio and most other popular book retailers.