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Concept Study of a Cislunar Outpost Architecture and Associated Elements That Enable a Path to Mars

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Concept Study of a Cislunar Outpost Architecture and Associated Elements That Enable a Path to Mars Concept Study of a Cislunar Outpost Architecture and Associated Elements that Enable a Path to Mars Presented by: Timothy Cichan Lockheed Martin Space [email protected] Mike Drever Lockheed Martin Space [email protected] Franco Fenoglio Thales Alenia Space Italy [email protected] Willian D. Pratt Lockheed Martin Space [email protected] Josh Hopkins Lockheed Martin Space [email protected] September 2016 © 2014 Lockheed Martin Corporation Abstract During the course of human space exploration, astronauts have travelled all the way to the Moon on short flights and have logged missions of a year or more of continuous time on board Mir and the International Space Station (ISS), close to Earth. However, if the long term goal of space exploration is to land humans on the surface of Mars, NASA needs precursor missions that combine operating for very long durations and great distances. This will allow astronauts to learn how to work in deep space for months at a time and address many of the risks associated with a Mars mission lasting over 1,000 days in deep space, such as the inability to abort home or resupply in an emergency. A facility placed in an orbit in the vicinity of the Moon, called a Deep Space Transit Habitat (DSTH), is an ideal place to gain experience operating in deep space. This next generation of in-space habitation will be evolvable, flexible, and modular. It will allow astronauts to demonstrate they can operate for months at a time beyond Low Earth Orbit (LEO). The DSTH can also be an international collaboration, with partnering nations contributing elements and major subsystems, based on their expertise. In addition to meeting human spaceflight objectives, the DSTH can help meet exploration science objectives. For example, astronauts in the DSTH could operate a robotic rover, in near real-time, to collect geological samples from lunar farside and return them to the outpost using an ascent vehicle. Returning samples from the South Pole–Aitken Basin (SPA) on the far side of the Moon has been identified as a priority in planetary science Decadal Surveys because it would help scientists understand the early dynamics and impact history of the solar system. Lockheed Martin is currently studying concepts for a DSTH architecture that evolves in capability over time. This work is being conducted both through internally funded work with partners like Thales Alenia Space Italy (TAS-I) and through the NASA-funded NextSTEP Habitat program. The architecture includes elements such as power and propulsion modules, habitation modules, cargo pods, and an Extra-Vehicular Activity (EVA) Module. The outpost’s capabilities increase with each new element, incorporating lessons learned and new technologies that are needed for Mars such as closed loop life support, laser communication, advanced EVA, In-Situ Resource Utilization (ISRU), and robotics. Acronyms/Abbreviations LPI: Lunar and Planetary Institute ARM: Asteroid Retrieval Mission NASA: National Aeronautics and Space DRO: Distant Retrograde Orbit Administration DSTH: Deep Space Transit Habitat PG: Proving Ground EM: Exploration Mission PGO: Proving Ground Objective EVA: Extra-Vehicular Activity SEP: Solar Electric Propulsion System FTO: Flight Test Objective SPA: South Pole–Aitken Basin ISRU: In-Situ Resource Utilization SLS: Space Launch System ISS: International Space Station TAS-I: Thales Alenia Space Italy LEO: Low Earth Orbit 2 Introduction mission scenario, the voyage to and from Mars In recent decades, the goal of human could last up to 12 months round-trip. This spaceflight has been to land astronauts on the transit time represents some of the most risky surface of Mars. However, that goal has always parts of the entire mission, due to the lack of seemed to be firmly on the horizon, just out of viable abort options. The challenges associated reach. Several architecture studies have been with Mars transits include: the increased crew conducted to determine the most efficient and autonomy due to long communication delays, safe method for conducting a Mars mission. the need for highly reliable and regenerative One thing they all seem to agree on is that life support systems, the mitigation of deep there are many variables involved and space radiation, spacecraft serviceability, Figure 1. Astronauts will need to learn to operate at much greater distances and durations than before in order to prepare for a mission to Mars. potential ways to get there. supplies and logistics, and the increased risks to crew health due to long stays in micro While there are many paths one could take to gravity. get to Mars, they all must deal the same core set of challenges. In general, the challenges of Astronauts have pushed the bounds of a Mars mission can be broken down into three human endurance in space. main categories, the long duration transits to Figure 1 depicts some of those achievements. and from the vicinity of Mars, the descent and A typical expedition on board the International ascent from the surface of Mars, and the actual Space Station (ISS) lasts around 180 days and stay on the surface of Mars. Depending on the in 2015-2016 Scott Kelly and Mikhail 3 Korniyenko spent 340 days at the ISS. The currently near completion, the Orion record for the longest stay in space goes to spacecraft and the Space Launch System (SLS) Valeri Polyakov, who spent 437 consecutive launch vehicle. Additional required elements days on Mir. Analysis of the long term effects and a mission architecture developed by of such extended stays in space is still Lockheed Martin and Thales Alenia Space Italy ongoing—and even Polyakov’s record is still both privately and as a part of the NASA about one half the duration of an entire Mars NextSTEP Habitation program are discussed in mission. this paper. While a stay on the ISS doesn’t come without Cislunar Proving Ground Architecture some risks, astronauts always have the ability To undertake a human mission to Mars, to abort their mission in the case of an extreme humans will need to develop the technology, emergency. Such scenarios can have a crew systems and capabilities necessary to live in back on the ground within hours of initiating deep space for extended durations. As a key the abort. On trips to Mars, that will not be the part of this preparation, NASA has established case. The orbits of Earth and Mars mean that a set of proving ground objectives (PGO) and mission opportunities only occur roughly every flight test objections (FTO) to identify what 2 years, and the propulsive requirements are needs to be accomplished in cislunar space [1]. too great to allow astronauts to return home NASA envisions three exploration phases that early in the case of an emergency. incrementally build toward Mars travel [2]. Humans have experienced this challenge to a The ISS is being used to begin the first phase, certain degree. During the Apollo missions, with ongoing research on the ISS aimed at astronauts traveled all the way to the Moon. developing techniques, protocols, and Their abort options to safely return to Earth technology needed for deep space travel. were measured in days not the minutes to Examples include maturation of highly hours of an ISS abort. For Mars there is no regenerative life support systems, tele- practical abort option. Even though the Apollo operation of rovers on Earth, and simulated program was a great achievement in human communications delays. NASA refers to this as spaceflight, those missions lasted only one to Phase 0. The next phase, Phase 1, pushes two weeks. A mission to Mars will take further out into deep space beyond the Van astronauts 1,000 times further away from Allen belts. The focus of Phase 1 is to gain Earth, and will last up to 3 years. confidence and understanding of the transportation systems used to access deep To address the challenges of a Mars mission, space, learning how to work in deep space and it’s clear that what is needed is a test program to make sure the crew stays healthy in the that allows engineers and astronauts to gain process. experience working in deep space for long durations, at long distances from Earth. Such a Pursuit of these objectives requires the program would increase both mission distance establishment of a Deep Space Transit Habitat and duration, addressing strategic objectives (DSTH). Astronauts will demonstrate crewed with increasingly complex missions. Such a flight operations in deep space and begin to program will also require a core set of deep increase crew autonomy. Once the majority of space elements. Two of these elements are the PGOs are achieved, NASA expects to use 4 the lessons learned to meet objectives for perform science missions that are directly Phase 2, which provides the final development applicable to exploring Mars with astronauts, that will enable travel to Mars. such as processing regolith into useful materials via In Situ Resource Utilization Phase 2 will include the addition of advanced (ISRU). Other objectives are met by operating elements that will serve as precursors to the at a greater distance from the Earth with time Mars transit elements. These new elements delays between the crew and Earth reaching will contain Mars-class systems such as closed- around twenty minutes. Crew health on loop life support and radiation protection. missions outside the protection of Earth’s They will also provide more habitable volume magnetic field or without an easy means to and greater power and propulsion capability. return to Earth quickly is a concern. The The validation of Mars-class elements and Proving Ground missions help broaden our vehicles will be accomplished with missions of understanding of and provide solutions for increasing duration and distance from Earth.
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