Journey to a star? (4)

I believe the answer is:

trek

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'journey' is the definition.
(I know that trek is a type of journey)

I don't understand the rest of the clue.

(Other definitions for trek that I've seen before include "Great journey" , "Footslog" , "Long hike" , "A long arduous march" , "Long walk, expedition" .)

I've seen this clue in the Evening Standard.

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