eli5: Does the light coming from the stars which are light years away still contain some heat or is it lost as the light travels?

Question

eli5: Does the light coming from the stars which are light years away still contain some heat or is it lost as the light travels?

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Answer 1

Need to clarify on some misunderstanding of the words “light” and “heat”.

What you call “light” IS electromagnetic radiation of some wave length.

What you call “heat” is, again, electromagnetic radiation of some wave length. Typically we call “heat radiation” light in the infrared spectrum, but to be precise light of any frequency can heat any surface that can absorb them (https://en.m.wikipedia.org/wiki/Infrared). And when I use the verb to “heat” it means to transfer energy that excites atoms and “makes them wiggle more”.

So, as an example, radiowaves used to transmit music are also light and they can also heat stuff. Any light of any spectrum can potentially heat stuff.