Queen pens article for Sky (5)
I believe the answer is:
ether
'for sky' is the definition.
(I've seen this before)
'queen pens article' is the wordplay.
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'pens' indicates putting letters inside.
'article' becomes 'the' (the definite article in English).
'er' placed around 'the' is 'ETHER'.
(Other definitions for ether that I've seen before include "Former anaesthetic" , "I'm volatile" , "Rare atmosphere" , "Medium supposedly" , "number" .)