"Henri Wilson" HW@.. wrote in message
...
If I take a copper sphere into deep space, what be its final temperature?
There isn't much out there but it still has a temperature.

My guess is about 3K.


The copper will come to thermal equilibrium with the backgroud radiation.
That is to say that the rate of thermal radiation which is emitted as black
body radiation will be the same as the rate at which the body absorbs the
thermal radiation. The CMBR has a distribution which is nearly identical to
a black body radiation. It's for that reason that the final temp will be 3K.

So why all this CMBR/BB crap?

What are you refering to? What is crap about it?

Pmb