New moon was spotted eventually by outdoor worker (8)
I believe the answer is:
woodsman
'outdoor worker' is the definition.
(someone who works in the woods)
'new moon was spotted eventually' is the wordplay.
'new' indicates an anagram.
'eventually' says to take the final letters.
The last letter of 'spotted' is 'd'.
'moon'+'was'+'d'='moonwasd'
'moonwasd' anagrammed gives 'WOODSMAN'.
'by' is the link.
(Other definitions for woodsman that I've seen before include "elder worker, perhaps?" , "outdoorsy type" , "He lives in the forest" .)