Crossword Genius

Brighten up space, as it happens, by noon (7)

Ross

I believe the answer is:

enliven

'brighten up' is the definition.
(I've seen this before)

'space as it happens by noon' is the wordplay.
'space' becomes 'en' (in printing, a space as wide as a letter 'n').
'as it happens' becomes 'live' (as in live broadcasting).
'by' means one lot of letters go next to another.
'noon' becomes 'n' (abbreviation).
'en'+'live'+'n'='ENLIVEN'

(Other definitions for enliven that I've seen before include "Put zip or vim into" , "Pep up" , "Inject vim into, energise" , "Excite" , "Wake" .)

I've seen this clue in The Daily Express.
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