The Exploration Gateway Platform[1] was a design concept proposed by Boeing in December 2011 to drastically reduce the cost of Moon, near Earth asteroids (NEAs), or Mars missions by using components already designed to construct a refueling depot and servicing station located at one of the Earth–Moon Lagrange points, L1 or L2.[2] The system claims its cost savings based on an ability to be reused for multiple missions such as a launch platform for deep space exploration, robotic relay station for moon rovers, telescope servicing and a deep space practice platform located outside the Earth's protective radiation belts.
The platform would be constructed at the International Space Station (ISS) for testing before being relocated to EM-L1 or EM-L2 via electric or chemical propulsion rockets.