Film dog in space orbit? (5)

I believe the answer is:

pluto

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'film dog' is the definition.
(Disney character)

I cannot understand how the rest of the clue works.

(Other definitions for pluto that I've seen before include "Planet beyond Neptune" , "Long-haul destination" , "Infernal ruler" , "Greek god of the underworld" , "heavenly body" .)

I've seen this clue in the Evening Standard.

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