Nonentity wrote article on the end of solar system (4-3)
I believe the answer is:
also-ran
'nonentity wrote' is the definition.
I can't tell whether this definition defines the answer.
'article on the end of solar system' is the wordplay.
'article' becomes 'a' (the indefinite article in English).
'the end of' indicates one should take the final letters.
'system' indicates anagramming the letters (another version or system with the same letters).
The last letter of 'on' is 'n'.
'n'+'solar'='nsolar'
'nsolar' with letters rearranged gives 'lsoran'.
'a'+'lsoran'='ALSO-RAN'
Can you help me to learn more?
(Other definitions for also-ran that I've seen before include "Not placed among winners, as in racing" , "Race loser" , "Not placed in the first three of horse race" , "Unplaced horse" , "Losing runner" .)