Group 1 tries to detect any signals from afar (4)

I believe the answer is:

seti

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'tries to detect any signals from afar' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'group 1' is the wordplay.
'group' becomes 'set' (both can mean a collection).
'i' becomes 'i' (Roman numeral).
'set'+'i'='SETI'

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I've seen this clue in The Irish Times.

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