My heavenly body's collapsed -- at rest on run going wrong (7,4)

I believe the answer is:

neutron star

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'my heavenly body's collapsed' is the definition.
I can't tell whether this definition defines the answer.

'at rest on run going wrong' is the wordplay.
'going wrong' is an anagram indicator.
'at'+'rest'+'on'+'run'='atrestonrun'
'atrestonrun' with letters rearranged gives 'NEUTRON STAR'.

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I've seen this clue in The Telegraph.

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