fauxtrot

script foxy

  • she/her

28yo trans dyke


My Website
fauxtrots.com/

Cynosura
@Cynosura

Fun facts:

Water ice doesn't absorb a lot of light in the visible; pure water ice is almost entirely transparent, although with slightly stronger absorption in the red (hence why very large amounts of mostly pure ice, such as glacial ice, has blue shading). What makes water ice much more visible comes from light scattering off impurities, air bubbles, or cracks (e.g. why ice cubes are sometimes clear and sometimes white, despite both being water ice).

It gets more interesting in the near-ultraviolet; between 200 and 400 nm, water ice is so transparent that we literally cannot measure the amount of light it absorbs. Even using deep boreholes in ultra-pure Antarctic ice, any loss of transparency is apparently dominated by scattering off impurities at levels of parts-per-billion. At the wavelength where absorption is lowest (~390 nm), our best estimate is that the mean free path of a photon in pure ice is over a kilometer; this makes water ice in the near-UV the most transparent solid known.


shel
@shel

And the end result is delicious



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in reply to @Cynosura's post:

Snow probably doesn't look that much different, I'd imagine- the appearance of snow is dominated by scattering, hence why it's white and opaque. At least for this kind of scattering, it's mostly wavelength-independent.

This went the exact opposite direction I was expecting. I figured you were gonna say something like it was actually opaque to IR, but I don't actually know if that's true.

I also now realize that I can actually test if this is true using an ice cube and a TV remote.

It does absorb light fairly strongly in certain parts of the IR, which are commonly used for certain remote sensing applications (e.g. weather satellites can use those absorption bands to determine the difference between ice clouds and water clouds) but those absorption bands are farther in the infrared than the barely-out-of-visible-range LEDs you usually see in TV remotes. The ones I'm most familiar with are at 1.5, 1.65, 2.0, and 3.0 microns.