Astronomical explosion of prunes wrecked eggs (9)
I believe the answer is:
supernova
'astronomical explosion' is the definition.
(exploding star)
'prunes wrecked eggs' is the wordplay.
'wrecked' indicates an anagram.
'eggs' becomes 'ova' (term for egg cells).
'prunes' is an anagram of 'supern'.
'supern'+'ova'='SUPERNOVA'
'of' acts as a link.
(Other definitions for supernova that I've seen before include "Star that explodes and becomes extremely luminous" , "it puts an end to a starry career" , "Exploding star that becomes extremely luminous" , "The sort of star" , "Star in decline" .)