Earth as an exoplanet mission concept for a lunar orbiting cubesat

Abstract

There is a growing interest in Lunar exploration fed by the perception that the Moon can be made accessible to low-cost missions in the next decade. The on-going projects to set a communications relay in Lunar orbit and a deep space Gateway, as well as the spreading of commercial-of-the shelf (COTS) technology for small space platforms such as the cubesats contribute to this perception. Small, cubesat size satellites orbiting the Moon offer ample opportunities to study the Moon and enjoy an advantage point to monitor the Solar System and the large scale interaction between the Earth and the solar wind. In this article, we describe the technical characteristics of a 12U cubesat to be set in polar Lunar orbit for this purpose and the science behind it. The mission is named EarthASAP (Earth AS An exoPlanet) and was submitted to the Lunar Cubesats for Exploration (LUCE) call in 2016. EarthASAP was designed to monitor hydrated rock reservoirs in the Lunar poles and to study the interaction between the large Earth's exosphere and the solar wind in preparation for future exoplanetary missions. Gateway 2 has open the path to the development of lunar cubesats. This new generation will need to confront important challenges such as the adaptation to interplanetary space or the development of communication strategies based on shared communications relays. Moon's orbit offers ample opportunities to study the Moon and enjoys an advantage point to monitor the the Solar System and the large scale interaction between the Earth and the solar wind. In recognition of this interest, the European Space Agency (ESA) focused the 2016 SysNova call on lunar cubesats (LUCE); ESA's SysNova calls open regularly 3 aiming at getting innovative proposals in space technology. LUCE Sysnova technical challenge was intended to address four different topics: lunar resource prospecting, environment and effects, science from or in the Moon and lunar exploration technology and operations demonstration. The first version of the project we present in this article was submitted to this call, though it was not selected it evolved and matured to address some critical challenges such as the required instrument miniaturization, the propulsion for orbit maintenance or the on-board autonomy assuming sparse communication windows to an international communication relay. The project was named Earth AS An exo-Planet (EarthASAP)as one of its key scientific objectives is using the lunar orbit vantage point to monitor the interaction between the Earth's exosphere and magnetosphere with the solar wind; also in preparation for the coming exoplanetary research missions.In the following sections the scientific objectives (section 2), the mission concept (section 3), the mission and data handling (section 4) are described. The article concludes with a brief summary together with the risk evaluation and the palliative solutions proposed by the team (section 5). 2 exploration.esa.int/moon/59374-overview/ 3 gsp.esa.int/sysnova