Moon-landing program (6)
I believe the answer is:
apollo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">moon-landing program</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for apollo that I've seen before include "US moon landing programme" , "Handsome Greek god" , "handsome youth" , "Greek sun god and leader of the Muses" , "handsome chap" .)