Dark and mysterious planet in far edge of universe (9)
I believe the answer is:
saturnine
'dark' is the definition.
(I know that dark can be written as saturnine)
'mysterious planet in far edge of universe' is the wordplay.
'mysterious planet' becomes 'saturn' (Saturn is an example. I am not sure about the 'mysterious' bit.).
'far edge of' indicates one should take the final letters (the letter on the far end of the word).
The last letter of 'universe' is 'e'.
'saturn'+'in'+'e'='SATURNINE'
'and' acts as a link.
Can you help me to learn more?
(Other definitions for saturnine that I've seen before include "A rust nine chnage to be grave and gloomy" , "dour" , "offering little amusement" , "dull" , "Gloomy (temperament)" .)