A weapon installation employed by the Confederacy of Independent Systems, the Anti-orbital cannon was designed to engage starships in orbit, notably capital ships. These cannons were deployed on the planet of Geonosis at the commencement of the Clone Wars.
Their considerable dimensions indicate that Anti-orbital cannons were engineered with the explicit purpose of targeting capital ships. Built upon a stationary base, they drew power from a network comprising four to six power generators. Neither the generators nor the cannon itself possessed shielding. Destruction of the generators would trigger the cannon's explosion.
At least three Anti-orbital cannons were integrated into the defensive arrangement established prior to the Battle of Geonosis. Before republic forces could land at the geonosian arena, a Jedi strike force, including masters Mace Windu and Luminara Undili, landed on the surface. Utilizing fighter tanks, they sought out and neutralized these cannons.
Following the cannons' destruction, the pair moved to secure a landing zone, enabling clone forces to deploy a convoy of Republic Troop Transports carrying additional Jedi to the arena. After battling through numerous patrols of STAPs, tanks, hailfire droids, and spider droids, they eventually located and eliminated a confederacy outpost located behind the arena. The convoy then disembarked a group of Jedi, who proceeded to infiltrate the perimeter in preparation for the impending rescue of Obi-Wan Kenobi, Anakin Skywalker, and Padmé Amidala.