Before the introduction of the v-150, anti-orbital ion cannons were considered to be an engineering impossibility. Nowadays, they are relatively commonplace. The v-150 consists of a spherical permacite shell thirty meters in diameter, and its power is supplied by a massive reactor that normally is buried nearly forty meters below ground level. When it is activated, the ion cannon swivles into position on its rotating base fairly quickly, while the blast shield retracts, exposing the cannon. A crew at twenty-seven soldiers is needed to operate the weapon and handle its targeting computers.