Behind time, jettisoning first of boosters over the moon (6)
I believe the answer is:
elated
'over the moon' is the definition.
(I've seen this before)
'behind time jettisoning first of boosters' is the wordplay.
I cannot quite understand how this works, but
'behind' could be 'late' and 'late' is found within the answer.
The remaining letters 'ed' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for elated that I've seen before include "Overjoyed, really delighted" , "In an enraptured state" , "Intensely happy" , "Delighted, ecstatic" , "In high spirits, very pleased" .)