Second asteroid's heading direct for planet (6)

I believe the answer is:

saturn

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'planet' is the definition.
(Saturn is an example)

I cannot understand how the remainder of the clue works.

(Other definitions for saturn that I've seen before include "space traveller" , "Roman god - gas giant" , "Giant planet" , "The dark planet" , "Turn as a planet" .)

I've seen this clue in The Telegraph.

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