Call up about fire in the sky (8)
I believe the answer is:
empyrean
'the sky' is the definition.
(I've seen this before)
'call up about fire in' is the wordplay.
'call' becomes 'name' (as in calling or naming someone something).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'about fire' becomes 'pyre' (as in a funeral pyre. I am not sure about the 'about' bit.).
'in' is an insertion indicator.
'name' reversed gives 'eman'.
'eman' placed around 'pyre' is 'EMPYREAN'.
Can you help me to learn more?
(Other definitions for empyrean that I've seen before include "vault of the sky, celestial heaven" , "Sublime; the highest heaven (arch.)" , "Relating to heaven" , "The heavens (poetic)" , "The celestial vault or firmament" .)