Lantean system
THE STARGATE OMNIPEDIA
LANTEAN SYSTEM
Star system where Atlantis is located. Comprised of nine planets (the fifth ringed) and an asteroid belt, the system became the last target of the Wraith after the species had successfully annexed all other planets in the galaxy. All weapons platforms, save one, were eliminated. The last platform was fifteen hours away from Atlantis's planet, Lantea.

Lantea is the fourth sphere from the sun in the Lantean system.

See also: siege of Atlantis (I), The

KEY EPISODE(S) -
The Defiant One - Sheppard takes a unit to an Ancient weapons platform recently detected on the long-range sensors, very near to another world in the Lantean system.
The Siege, Part 2 - At Colonel Everett's request Sheppard explains the history behind the first siege of Atlantis, and how the Lantean system was the last to fall.