The Lunar Gateway is an in-development space station being planned by several national space agencies, including NASA, ESA, CSA and Australian Space Agency. It is planed to be placed in lunar orbit and intended to serve as a solar-powered communications hub, science laboratory, short-term habitation module, and holding area for rovers and other robots. It would play a major role in NASA's Artemis program. Computer simulations indicate that this orbit offers long-term stability with low propellant requirements for orbital station-keeping, by using a precise balance point in the gravities of Earth and the Moon that offers a stable trajectory. The main objective of the CAPSTONE mission is to verify the calculated orbital stability simulations for the Gateway. CAPSTONE will be the first spacecraft to operate in that unique lunar orbit. The spacecraft will also test a navigation system called Cislunar Autonomous Positioning System, that will measure its position relative to NASA's Lunar Reconnaissance Orbiter without relying on ground stations.
Spacecraft
The orbiter is a 12-unit CubeSat. The $13.7 million contract was awarded to a private company called Advanced Space, Boulder, Colorado, on 13 September 2019 through a federal Small Business Innovation Research contract. Advanced Space will handle overall project management and some of the spacecraft's key technologies, including its CAPS positioning navigation system, while Tyvak Nano-Satellite Systems, Irvine, California, will develop and build the spacecraft platform and its propulsion systems. NASA announced on 14 February 2020, that CAPSTONE will be launched aboard a booster Electron of Rocket Lab from the company's new launch site, Launch Complex-2 at the Mid-Atlantic Regional Spaceport, Wallops Island, in Virginia, and the launch is scheduled for early 2021. Following a three-month trip to the Moon, the CAPSTONE lunar satellite will spend six months collecting data during this demonstration. Rocket Lab's new launch pad in Virginia, designated Launch Complex 2, was completed in 2019 and will be ready to support launches in 2020. The company said the new facility will primarily support Electron missions with U.S. government payloads. The launch contract with Rocket Lab — U.S.-based company that currently launches from New Zealand — has a value of $9.95 million, according to NASA.