Group of stars going round current American city (8)
I believe the answer is:
columbia
'american city' is the definition.
(name of several US cities)
'group of stars going round current' is the wordplay.
'group of stars' becomes 'Columba' (Columba is a constellation).
'going round' means one lot of letters goes inside another (some letters go around others).
'current' becomes 'I' (symbol for electric current).
'columba' enclosing 'i' is 'COLUMBIA'.
(Other definitions for columbia that I've seen before include "record label" , "University in New York City" , "The C in Washington DC" , "River - capital of South Carolina" , "British -, Can. province" .)