Cloud of interstellar gases and dust (6)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
nebula
(Other definitions for nebula that I've seen before include "Gas/dust cloud in space" , "Unable (anag)" , "Mist of gas or stars in the night sky" , "Hazy light; a slight cloudiness" , "Unable to find patch in the sky" .)