A New Approach for Aerobraking at Mars: Return to Earth

Abstract

‡ASI, Agenzia Spaziale Italiana, Rome, Italy Intro duction Main efforts of modern aerospace research are focused on interplanetary missions and solar system exploration: in current situation, technologies allow us to realize an unmanned one way mission. Next step of the research is obviously a round trip around other solar planet, and a safe return to Earth. Several ideas, about this purpose, were developed: our work wants to bring new perspectives on return phase research. In particular, we started from a simple idea: use of a free of charge refuelling st ation on mars orbit! It seems a crazy idea, but the use of aerobraking manoeuvre on Mars atmosphere to reach a stable orbit and to save propellant during the orbit insertion is a common practices. Having motors that are able to use carbon dioxide as prope llant it makes possible to use the atmosphere captured during the aerobraking for the re -fuelling. The work hereafter described was aimed to verify the feasibility of this type of mission. This mission evaluation gives a rough verification of the feasibil ity that can be used to identify the main subsystems needed for Mars return mission. This activity is based on already available technologies, even if used in original way, permitting us to investigate about the chance of decrease weights and initial volu mes (costs) and improve the reliability. First step of our investigation was the identification of thrusters compatible with Mars atmosphere composition and performances. Once obtained propulsion solution we had useful data to predict and evaluate mission scenarios, in which we could suppose future applications to our system: departing from a theoretical choose of the orbital condition and consequently the launcher performances. The need of having important performances in terms of velocity and an acceptab le PL mass Mars bring to identify the most powerful European launcher, the Ariane 5, also the launcher fairing’s dimensions are more than comfortable for mission needs. The identification of the Power Supply and Management subsystem typology, characteristi cs and performances starting from the engine characteristics, is performed in order to allocate mass and technological feasibility. The mission scenario s are the basis for the thermal and mechanical loads acting on the inflatable structures. This kind of technology is already used for Mars environment and more research believe s that could be the future for interplanetary mission in the Solar system. Our purpose is to better define the new utilisation for inflatable thermal protections to be used as dynamic inflatable inlet (that allow us to project a piece characterized by a large area ratio). To verify if the inflatable pressure vessels can be used in order to store the captured gas, for the return flight saving mass and increasing the reliability. Miss ion scenarios