The most common and most likely answer to this crossword clue is the 8 letter word MOONSHOT
I've seen this crossword clue in The Times
M
O
O
N
S
H
O
T
More clues leading to the result MOONSHOT
- Apollo mission perhaps uncovers seat, radioactive
- Wander around quiet books launch
- Space launch low over poles, hard to put up
- Wanders listlessly, very keen for space travel
- Working quietly to block debatable space mission
- Drummer at bash for Apollo launch?
- Wander around with mum before books launch
- Doctor Smooth on mission to attain heavenly body?
- Space flight is rather aimless, creating news
- Working belt up in dispute, one has very high target
Buddy explains!

The straight part
We know that "Space launch" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case space launch = moonshot.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.
What does MOONSHOT mean?
MOONSHOT noun- The launching of a spacecraft or an object to orbit or land on the Moon.
- An act of throwing or hitting a ball with a high trajectory.
- An expensive, hard, or unlikely task of great potential impact.