Endless danger? Gosh — it's where something is as close as possible! (7)
I believe the answer is:
perigee
'where something is as close as possible' is the definition.
The answer is a location as well as being a singular noun. This is suggested by the definition.
'endless danger? gosh' is the wordplay.
'endless' means to remove the last letter.
'danger?' becomes 'peril' ('peril' can be a synonym of 'danger').
'gosh' becomes 'gee' (I've seen this before).
'peril' with its last letter taken off is 'peri'.
'peri'+'gee'='PERIGEE'
'it's' acts as a link.
Can you help me to learn more?
(Other definitions for perigee that I've seen before include "Lowest orbit point" , "Point of orbit closest to the earth" , "Point where the Moon is closest to the Earth" , "Point of closest approach" , "where orbit's lowest" .)