Re: Blacker than Black

Tom B schrieb:

> I guess this explains to some extent why many stealth planes and ships
> put a premium on surfaces angled to bounce incoming radar waves away
> in some orthogonal direction rather than directly back at the emitter
> (and thus presumably at the reciever).
> 
> It doesnt exactly tell me why the B2 and F-117 were black (if this is
> crappy for thermal stealth), but perhaps the radar threat and visual
> observation issues were more critical than thermal stealth in the
> design process.

I assume that the stealth planes are black because they are supposed to 
operate at night and black provides visual camouflage.

Note that there is a significant difference between heat radiation in 
space and on earth. Space is *cold* - some 3 degrees above absolute 
zero. Any object warmer than that is a net radiator.

On Earth the athmosphere and every object is warm, some 270 degrees 
Kelvin, and everythings radiates heat and receives heat radiation from 
everything else. So if something is at room temperature it will not 
register on aheat sensor. So thermal camouflaging is easier on Earth.

Greetings
Karl Heinz