No Lynn, Its not for pelting rocks at the moon, but your close. Its part of a circulotometer
that creates an explosive backpressure at large proporsions after detonation
which directs heavy metalic and "HE" particles towards the ionsphere
which then it either engages another self propelled object or physics return the object to level ground
where it disintegrates on impact.
Abbreviated called a "Bofor" Darth vater and his brother exca had one
I hope all this technical stuff has'nt confused you.
Regards
Colin