Space vehicle (7)
I believe the answer is:
orbiter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">space vehicle</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for orbiter that I've seen before include "Craft going round planet" , "Non-landing spacecraft" , "One goes round" , "Circling spacecraft" , "Satellite perhaps" .)