First man in space — right in going? Crazy (4)
I believe the answer is:
gaga
'crazy' is the definition.
(I know that crazy can be written as gaga)
I don't understand the remainder of the clue.
(Other definitions for gaga that I've seen before include "US singer Lady ___" , "Doddery" , "Lady < > in a senile" , "fatuous?" , "Senile - slightly crazy" .)