Homemade Ice Sheets
Are ice crystals different in microgravity? I had a look.
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Last weekend I asked if I could use one of the research freezers onboard Space Station during my off-duty time. I made thin sheets of water about a millimeter thick (sort of like a soap film, but without the soap), and froze them. Then I looked at the ice under polarized light, using a laptop display as the light source for one direction of polarized light and a filter I just happened to have in my personal kit to make “crossed polarizers.”
When the ice sheets were placed between the filter and the laptop screen, the crystal structure became vividly visible. I do not know at this time if the crystal structure is any different than normal ice, but I will find out.
Meanwhile, we were unloading the supplies from Dragon.
Above and below: ice sheets in polarized light.
An ice sheet in ordinary light, and my polarizer setup (below).
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