The most common and most likely answer to this crossword clue is the 3 plus 3 plus 2 plus 3 plus 4 letter word THE MAN IN THE MOON
I've seen this crossword clue in Independent
T
H
E
M
A
N
I
N
T
H
E
M
O
O
N
More clues leading to the result THE MAN IN THE MOON
Buddy explains!
The straight part
We know that "Fellow with a heavenly body looked up to" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fellow with a heavenly body looked up to = the man in the moon.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.