I foresee that this word is going to cause a heap of trouble in the future because there are two moonshots with two different etymologies which have already become confused.
The first moonshot is in Macquarie Dictionary and refers to the Apollo 11 successful landing on the moon in 1969. The discussions leading up to this are documented from 1949.
The second moonshot is an Americanism and refers to a baseball player called Wally Moon who had the habit of hitting the ball over the left-boundary fence. His style was somewhat unorthodox but it got results.
The OED keeps these two moonshots as separate entries but Merriam-Webster naughtily rolls them together as one. The internet reveals total confusion.
The use of moonshot has developed today to mean ‘an enterprise which is hugely ambitious but a leap into the dark, one which brings enormous benefits if it succeeds but which could just as easily be a total and expensive failure’.
This derives from the first moonshot, the brave decision made by NASA and supported by JFK to work towards putting a human being on the moon, and bringing them back to earth.
Of course Australians on the whole don’t know the baseball jargon and have probably never heard of Wally Moon, so we could be less confused than the Americans.