Can water produce light when heated?

Question

I am asking this regarding blackbody radiation. Water is not black, obviously. I read it is very lightly blue, but it is mostly transparent in liquid form so it probably does not absorb much of the visible spectrum nor emit anything at least at low temperatures. In solid or gazeous form it is mostly transparent too. However, if water is heated to extremely high temperatures, whatever its phase and pressure, can it produce light?

fraxinus · Accepted Answer

Water (in more or less normal conditions) has just a tiny "window" of transparency  at and around the visible light.
(image from https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_water)
One can pretty much feel the thermal infrared radiation near a hot (sub-boiling) water.
In order to see significant visible light emitted from water, you have to heat it a lot. In particular, burning a hydrogen in air does not produce enough heat for a flame to be visible and this is considered a danger. If you have enough line-of-sight inside the flame and it is dark enough, some tiny light is visible (by eyes).
Then again, given enough heat, water will decompose and ionize. A plasma with enough free electrons is pretty good at emulating a blackbody.

Can water produce light when heated?

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