Moon of Saturn in forbidden path making top news item (6,8)
I believe the answer is:
banner headline
'top news item' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'moon of saturn in forbidden path' is the wordplay.
'moon of saturn' becomes 'rhea' (I've seen this in another clue).
'in' is an insertion indicator.
'forbidden' becomes 'banned' (banning is a kind of forbidding).
'path' becomes 'line' (I can't justify this - if you can you should give a lot more credence to this answer).
'rhea' placed within 'banned' is 'bannerhead'.
'bannerhead'+'line'='BANNER HEADLINE'
'making' is the link.
Can you help me to learn more?
(Other definitions for banner headline that I've seen before include "Newspaper front page item" , "Streamer" .)