Industry that could explore Milky Way's chocolate bar range (9)
I believe the answer is:
aerospace
'industry that could explore milky way's chocolate' is the definition.
'aerospace' can be an answer for 'industry' (aerospace is an industry or area of business). I am not sure about the rest of the definition.
'bar range' is the wordplay.
'bar' becomes 'Aero' (chocolate bar).
'range' becomes 'space' (I can't justify this - if you can you should believe this answer much more).
'aero'+'space'='AEROSPACE'
Can you help me to learn more?
(Other definitions for aerospace that I've seen before include "Opera case (anag)" , "Technology of planes, rockets, etc" , "Branch of technology including aviation" , "Technology of flight" , "rocket industry" .)