Klorel, using his Ha'tak in association with Apophis' Ha'tak, led an invasion against Earth. Klorel led the arrival, with Apophis arriving sometime later to coordinate the invasion. SG-1, using the coordinates of the location of Klorel's Ha'tak, arrived on the vessel and began to sabotage it with C-4 explosive to prevent the invasion of Earth. Although SG-1 was stopped once, assistance from Bra'tac allowed SG-1 to continue it's mission and ultimately set Klorel's Ha'tak to collide with Apophis' upon the C-4 detonating, effectively destroying both ships. (SG1: "Within the Serpent's Grasp", "The Serpent's Lair")
The same coordinates of Earth applied while the Ha'tak was in orbit above it.