Thanks Steven. Your explanation (for the absorption/emission relationship) makes it (deceptively) simple.
Cheers
Different topic …back to my original quest to fin out why Infrared Spectroscopy of Comets from Earth/Orbital platforms "doesn't work" (Ms Sunshine's words) …
I found a
great paper on this (Dated 6th Oct 2010, 10.MB), and it seems the dust emanating from these beasties causes polarisation of light in different parts of the absorption spectra. This seems to cause all sorts of problems for which they've developed corrective measures (theoretically based).
There's a lot more issues/material to read up on in order to understand Jessica's comment. No great surprise (to those of us who accept our lack of knowledge for not understanding things ..
)
I'm getting cheeky .. time to go and enjoy the beautiful weather !
Cheers, Rgds & thanks to all for your time/explanations.