Apropos of "Space: 1999" and hypothetically speaking of course, how big of a nuclear explosion would be needed to blow the moon out of orbit? How fast would it then travel?

The_Agouti

The escape velocity of earth, at the moons orbit (384,400 km) is 1.44 km per second. No nuclear bomb comes even close to the required energy (The moon weighs in at 7.36 x 10^22 kg (73,600,000,000,000,000,000 tons), so the energy required is about 1.53 x 10^29 (152,616,960,000,000,000,000,000,000,000) Joules, assuming that you vectored the explosion to put all the energy in the right directions (explosions normally express their energy unilaterally in all directions)). By comparison The atomic bomb dropped on Hiroshima created 5.2 x 10^13 Joules of energy, and only a fraction of a bomb exploded on the surface of the moon would actually be transferred into pushing it away. Even vectored, you would need over one thousand million Hiroshima bombs, and even with several bombs the moon would be broken up into fragments. At the energy required, it would probably just become a asteroid cloud. Jul 01 07, 9:09 PM