NASAA Special Publication 6107 Human Exploration of Mars: The Reference Mission of the NASA Mars Exploration Study Team Stephen J. Hoffman, Editor David I. Kaplan, Editor Lyndon B. Johnson Space Center Houston, Texas July 1997 Foreword Mars has long beckoned to humankind interest in this fellow traveler of the solar from its travels high in the night sky. The system, adding impetus for exploration. ancients assumed this rust-red wanderer was Over the past several years studies the god of war and christened it with the have been conducted on various approaches name we still use today. to exploring Earth’s sister planet Mars. Much Early explorers armed with newly has been learned, and each study brings us invented telescopes discovered that this closer to realizing the goal of sending humans planet exhibited seasonal changes in color, to conduct science on the Red Planet and was subjected to dust storms that encircled explore its mysteries. The approach described the globe, and may have even had channels in this publication represents a culmination of that crisscrossed its surface. these efforts but should not be considered the final solution. It is our intent that this Recent explorers, using robotic document serve as a reference from which we surrogates to extend their reach, have can continuously compare and contrast other discovered that Mars is even more complex new innovative approaches to achieve our and fascinating—a planet peppered with long-term goal. A key element of future craters, cut by canyons deep enough to improvements to this document will be the swallow the Earth’s Grand Canyon, and incorporation of an integrated robotic/human shouldering the largest known volcano in the exploration strategy currently under solar system. They found intriguing evidence development. that water played an important role on Mars with channels that bear a striking We will continue to develop alternative resemblance to stream beds and clouds of approaches, technologies, precursor missions, crystalline ice that still traverse its red sky. and flight demonstrations that collectively But they also found that Mars was cold and move us forward. Inputs have been, and will dry, and believed to be devoid of life. always be, encouraged from all sources— NASA centers, industry, research Now present day explorers have organizations, entrepreneurs, government announced that pieces of Mars have arrived agencies, international partners, and the on Earth as meteorites, and that these bits of public at large—which will improve our the red planet contain evidence pointing to understanding and current planning. We the possible existence of life early in Mars plan to use the results of these assessments to history. This has resulted in renewed public shape our investments in technology, and to III look for high leverage, innovative, break- must search for alternatives to substantially through approaches to the most cost effective reduce the cost of exploration, while exploration. These data will also help us increasing the inherent value to humankind. understand the required infrastructure, as This Reference Mission provides a viable well as provide important insights into how starting point for NASA’s continuing efforts we can use the International Space Station to to develop the technologies and systems, as validate key assumptions and technologies. well as the international partnerships, needed for the grand adventure of sending humans to To achieve our goal, we must explore another planet in our solar system— fundamentally change the way in which we one that may have once, and may yet again, explore with both humans and robots. We harbor life. IV Acknowledgments Sending people to Mars has been a will be added to and improved upon by long-held dream of humankind, and many others in the future. This report has benefited have approached the task of turning the from the contributions and advice of many dream into reality. This document is another individuals from the government and private chapter in the ongoing process of melding sectors. The individuals listed on the new and existing technologies, practical following page assisted in preparing the operations, fiscal reality, and common sense concepts described in this report and in into a feasible and viable human mission to compiling the words, images, and data used Mars. However, this is not the last chapter in for that description. the process, but marks a snapshot in time that Stephen J. Hoffman David I. Kaplan V Contributing Authors Los Alamos National Laboratory: Dr. Paul Keaton Ames Research Center: Roger Arno Marshall Space Flight Center: Dr. Geoff Briggs William Huber Dr. Yvonne Clearwater General Contributors Dr. Marc Cohen Andy Gonzales Ames Research Center: Betsy Dunsky Johnson Space Center: Paul Espinosa Dr. Michael Duke Vladimir Garin David Kaplan Lynn Harper Catherine Larson Butler Hine David Weaver Larry Lemke Laurie Weaver Doug O’Handley Lewis Research Center: Nelson Schlater Robert Cataldo Michael Sims Dr. Stanley Borowski Boeing: SAIC: Brent Sherwood Dr. Stephen Hoffman Lewis Research Center: Paul Phillips Dr. Stanley Borowski Study Team Members Rockwell International: Ames Research Center: Robert Raasch Dr. Geoff Briggs (co-lead) Lisa Rockoff Johnson Space Center: Reviewers and Commenters Jeri Brown Johnson Space Center: Nancy Ann Budden Nancy Ann Budden Beth Caplan John Connolly John Connolly Dr. Michael Duke (co-lead) Other Support and Contributions Dallas Evans Dr. Steve Hawley Ames Research Center: Kent Joosten Dr. Chris McKay David Kaplan Jeff Moore Darrell Kendrick Dr. Carol Stoker Barbara Pearson Anthony Gross Barney Roberts Editorial and Graphics Support Ed Svrcek David Weaver J. Frassanito and Associates: J. Frassanito Lewis Research Center: Dr. Stanley Borowski SAIC: Robert Cataldo R. Patrick Rawlings VI There is a set of supplemental technical reports which provide greater depth into many of the design features of the Mars Reference Mission than is given in section 3 of this document. Had those papers been included as appendices, the size of this document would have greatly expanded. Consequently, we decided to make those supplemental materials available through the world wide web. We intend to post new materials as to the web as they are produced and hope to maintain a site with the latest information which describes key technologies and design features of a human mission to Mars. The site for the Mars Reference Mission is http://www_sn.jsc.nasa.gov/marsref/contents.html VII VIII Contents Section Page Acronyms .................................................................................................................................................... xv 1. OVERVIEW AND EXECUTIVE SUMMARY ..................................................................................... 1-1 1.1 INTRODUCTION ..................................................................................................................................... 1-3 1.2 BACKGROUND........................................................................................................................................ 1-5 1.3 REFERENCE MISSION EXECUTIVE SUMMARY .............................................................................. 1-6 1.3.1 Objectives ...................................................................................................................................... 1-6 1.3.2 Groundrules and Assumptions .................................................................................................. 1-7 1.3.3 Mission and Systems ................................................................................................................... 1-8 1.3.3.1 Mission Design ............................................................................................................. 1-8 1.3.3.2 In Situ Resource Production ..................................................................................... 1-16 1.3.3.3 Flight Crew ................................................................................................................. 1-16 1.3.3.4 Robotic Precursors ..................................................................................................... 1-17 1.3.3.5 Launch Systems .......................................................................................................... 1-18 1.3.3.6 Interplanetary Transportation Systems .................................................................. 1-18 1.3.3.7 Surface Systems .......................................................................................................... 1-22 1.3.3.8 Operations ................................................................................................................... 1-24 1.3.3.9 Mission and Systems Summary ............................................................................... 1-27 1.4 TESTING PRINCIPAL ASSUMPTIONS AND CHOICES ................................................................ 1-28 1.4.1 Robust Surface Infrastructure .................................................................................. 1-28 1.4.2 Split Mission Strategy ................................................................................................ 1-28 1.4.3 Nuclear Thermal Propulsion .................................................................................... 1-30 1.4.4 In Situ Resource Utilization ...................................................................................... 1-30 1.4.5 Common Habitat Design .........................................................................................