Observed being famous (5)
I believe the answer is:
noted
This clue is a double definition.
'observed' is the first definition.
('note' can be a synonym of 'observe')
'famous' is the second definition.
(noted can mean well-known or famous)
'being' acts as a link.
(Other definitions for noted that I've seen before include "Observed or took account of" , "Indicated" , "remarked upon" , "saw" , "Famous, well-known - entered into little book" .)