Is road (bitumen) a black body ?

answers1: Per Wikipedia "A black body is an idealized physical body
that absorbs all incident electromagnetic radiation, regardless of
frequency or angle of incidence" <br>
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Also from Wikipedia: " By definition, a black body in thermal
equilibrium has an emissivity of ε = 1.0." <br>
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Amazingly Asphalt pavement has an emissivity of around 0.93! (data
from Cole-Parmer TechLibraryArticle/254) So it's not a "black body". A
material such as this is referred to as a "gray body". <br>
<br>
The closest material to a perfect black body is made of vertically
aligned carbon nanotubes and absorbs 97 to 99% of incident radiation.
(ie. ε = .97 to .99) ("A black body absorber from vertically aligned
single-walled carbon nanotubes"
http://www.pnas.org/content/106/15/6044.long) <br>
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"Is there any radiation that can penetrate it? " <br>
Well no. <br>
By definition a perfect black body absorbs all incident radiation. In
practice with real materials this is not the case. <br>
<br>
MeanRoy