Dark planet in the east (9)

I believe the answer is:

saturnine

'dark' is the definition.
(I know that dark can be written as saturnine)

'planet in the east' is the wordplay.
'planet' becomes 'Saturn' (Saturn is an example).
'the east' becomes 'E' (synonyms).
'saturn'+'in'+'e'='SATURNINE'

(Other definitions for saturnine that I've seen before include "shining? The opposite" , "moody" , "may be brooding" , "dismal" , "Gloomy (temperament)" .)

I've seen this clue in The Telegraph.

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