Once again is Earth in grave danger and once again it is you who shall save our planet. Today the planet is in danger thanks asteroids, aliens and other deadly things. You are stationared on the Moon and with your laser tower you shoot everything what can destroy the population. The population number is your health, zero means you have lost the game. For every hit you get some money for improvements and defensive satellites. And that is all, do not wait something original or neveredning fun.