Aerospace science (8)
I believe the answer is:
rocketry
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">aerospace science</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for rocketry that I've seen before include "Propulsion of missiles" , "Study of space vehicles" , "NASA's expertise" , "Clever science" , "Powerful science" .)