A Mark IX is a naquadria enhanced nuclear bomb, also known as a "star destroyer buster". Developed primarily by Samantha Carter, it is a long cylindrical device meant to destroy everything within a 100 miles radius, including the otherwise indestructible Stargate. It has a several (at least 10) gigaton yield. When deactivated, it is in "mode 3", yet from "mode 2" it is extremely volatile. Any effort to disrupt, alter or destroy the device will lead to the weapon detonating immediately.