New legislation isn't lost on this old astronomer (7)
I believe the answer is:
galileo
'this old astronomer' is the definition.
'galileo' can be an answer for 'astronomer' (I've seen this before). I'm not certain of the 'this old' bit.
'new legislation isn't lost' is the wordplay.
'new' indicates an anagram.
'lost' indicates named letters should be taken away.
'legislation' with 'isnt' taken away is 'leglaio'.
'leglaio' with letters rearranged gives 'GALILEO'.
'on' is the link.
Can you help me to learn more?
(Other definitions for galileo that I've seen before include "Famous Italian" , "US unmanned space-craft launched in 1989 to investigate Jupiter" , "Sixteenth and seventeenth century Italian astronomer tried for heresy" , "Italian astronomer who had trouble with church" , "Italian astronomer, a founding father of modern science" .)