Phased ion cannon

From Memory Alpha, the free Star Trek reference.

The phased ion cannon is a powerful planet-based weapon that fires phased ion charges, capable of striking starships in orbit.

The homeworld of the Mokra Order in the Delta Quadrant possessed more than 85 phased ion cannon emplacements. In 2372, these cannons opened fire on the USS Voyager as it attempted to rescue its away team from the surface. The starship was able to evade the cannon fire for a few minutes by hiding in a magnetic storm over the north pole, which confused the Mokra targeting sensors. (VOY: "Resistance")