Dreamers in space organised time aboard research satellite (9)
I believe the answer is:
escapists
'dreamers' is the definition.
('escapist' can be a synonym of 'dreamer')
'space organised time aboard research satellite' is the wordplay.
'organised' indicates anagramming the letters.
'time' becomes 't' (abbreviation).
'aboard' means one lot of letters goes inside another.
'research satellite' becomes 'ISS' (International Space Station).
't' inserted into 'iss' is 'ists'.
'space' with letters rearranged gives 'escap'.
'escap'+'ists'='ESCAPISTS'
'in' is the link.
(Another definition for escapists that I've seen is " dreamers".)