LunarCube for Deep Space Missions

Busek Co., Inc. and Morehead State University propose to develop a 6U CubeSat capable of reaching a lunar orbit from GEO. The primary objective is to demonstrate heretofore unavailable high Isp(~3000s) with a small and very efficient ion thruster. A mission to the moon will demonstrate a propulsion technology that enables a variety of other deep space missions. Unlike the well-known and much larger DC ion thrusters flown on missions such as Deep Space 1 and Dawn, the proposed thruster is powered by an inductively coupled RF discharge with condensable propellant. The chosen propellant is stored as a high-density solid at room temperature with minimal vapor pressure. Such property enables the storage tank to be small, lightweight and moldable for maximizing propellant volume. These benefits are further realized by the use of Busek's miniature RF ion thruster (RFIT) system. Busek's ion thrusters were developed to answer the need for a small yet high-performance EP device, as their DC counterparts are difficult to scale down and achieve long life due to the internal cathode. The BRFIT-3 thruster proposed for the LunarCube has a 3cm grid diameter, is close to 50% efficient and delivers variable Isp and thrust of ~3000s and ~2mN, respectively. With this performance, 3km/s. The thruster's life by estimation is in excess of 20,000 hours. An additional objective is to demonstrate that much of the spacecraft electronics, primarily the C&DH portion, can be based on low-cost components and survive the deep space environment. The mission will also require pioneering approaches to ADCS and power generation. Initial design of the solar arrays includes two winged panels mounted on Honeybee Robotics' gimbals, and together they will deliver peak power of ~96W. One option for the payload will be a miniature long wavelength IR camera made by Malin Space Science Systems that could be used for geological studies.