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The Near-Earth Asteroid Rendezvous (NEAR-Shoemaker) Mission / Howard E

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The Near-Earth Asteroid Rendezvous (NEAR-Shoemaker) Mission / Howard E I-38738 NEAR BookCVR.Fin2 3/10/05 11:58 AM Page 1 d National Aeronautics and Space Administration Office of External Relations Low-CostLow-Cost History Division Washington, DC 20546 InnovationInnovation inin SpaceflightSpaceflight TheThe NearNear EarthEarth AsteroidAsteroid RendezvousRendezvous (NEAR)(NEAR) ShoemakerShoemaker MissionMission Monographs in Aerospace History No. 36 • SP-2005-4536 fld I-38738 NEAR BookCVR.Fin2 3/10/05 11:58 AM Page 2 Cover (from the top): The cover combines a closeup image of Eros, a photograph of the 1996 launch of the Near Earth Asteroid Rendezvous (NEAR) expedition, and a picture of the mission operations center taken during the second year of flight. NEAR operations manager Mark Holdridge stands behind the flight consoles. Asteroid and operations center photographs courtesy of Johns Hopkins University/Applied Physics Laboratory. Launch photograph courtesy of the National Aeronautics and Space Administration. (NASA KSC-96PC-308) Howard E. McCurdy Low-Cost Innovation in Spaceflight The Near Earth Asteroid Rendezvous (NEAR) Shoemaker Mission The NASA History Series Monographs in Aerospace History Number 36 NASA SP-2005-4536 National Aeronautics and Space Administration Office of External Relations History Division Washington, DC 2005 Library of Congress Cataloging-in-Publication Data McCurdy, Howard E. Low cost innovation in spaceflight : the Near-Earth Asteroid Rendezvous (NEAR-Shoemaker) Mission / Howard E. McCurdy. p. cm. — (Monographs in aerospace history ; no. 36) 1. Microspacecraft. 2. Eros (Asteroid) 3. Astronautics—United States—Cost control. 4. Outer space—Exploration—Cost control. 5. United States. National Aeronautics and Space Administration—Appropriations and expenditures. I. Title. II. Series. TL795.4.M34 2004 629.43’544—dc22 2004018515 Table of Contents iv List of Tables v Acknowledgments 1 Chapter 1: Challenge 5 Chapter 2: Origins 17 Chapter 3: Spacecraft 35 Chapter 4: Flight 51 Chapter 5: Legacy 59 Endnotes 69 Abbreviations 71 About the Author 73 NASA History Monographs iii List of Tables 11 Table 2-1 Mass Summary 18 Table 3-1 Planned Cost of NEAR Mission 18 Table 3-2 Selected Spacecraft Development Costs 22 Table 3-3 Actual Mission Costs: NEAR and Mars Pathfinder 23 Table 3-4 Cost of NEAR Scientific Instruments 31 Table 3-5 APL Management Guidelines for Low-Cost Missions iv Acknowledgments In preparing this monograph, the author was assisted by officials at the Johns Hopkins University Applied Physics Laboratory, the Jet Propulsion Laboratory, and NASA Headquarters. He wishes to acknowledge the assistance of persons who reviewed the manuscript or otherwise provided support for its production, especially Stamatios M. Krimigis, Andrew F. Cheng, Robert W. Farquhar, Stephen Garber, Roger D. Launius, Jennifer Troxell, Matthew Rochkind, Jill Wilmoth, Lisa Jirousek, Tatiana Floyd, and Henry Spencer. v Chapter 1: Challenge n a spring day in 1996, at their research center funding the Near Earth Asteroid Rendezvous Oin the Maryland countryside, representatives (NEAR) mission in late 1993. They had assigned from the Johns Hopkins University Applied Physics the mission to the Applied Physics Laboratory, a Laboratory (APL) presented Administrator Daniel not-for-profit research and development division of S. Goldin of the National Aeronautics and Space Johns Hopkins University located on a 365-acre Administration (NASA) with a check for $3.6 mil- campus between Baltimore, Maryland, and lion.1 Two and a half years earlier, APL officials had Washington, DC. Scientists and engineers from the agreed to develop a spacecraft capable of conduct- laboratory’s Space Department ran the mission. The ing an asteroid rendezvous and to do so for slightly Space Department at APL had come into being in more than $122 million. This was a remarkably low 1959 to build navigation satellites for the United sum for a spacecraft due to conduct a planetary- States Navy. Although increasingly involved in class mission. By contrast, the Mars Observer NASA work, APL scientists and engineers had spacecraft launched in 1992 for an orbital ren- never managed a major planetary mission. That dezvous with the red planet had cost $479 million responsibility commonly fell to the Jet Propulsion to develop, while the upcoming Cassini mission to Laboratory (JPL), a NASA Field Center in Pasadena, Saturn required a spacecraft whose total cost was California, operated by the California Institute of approaching $1.4 billion. In an Agency accustomed Technology. to cost overruns on major missions, the promise to build a planetary-class spacecraft for about $100 Officials at the Applied Physics Laboratory million seemed excessively optimistic. spent 27 months designing, constructing, and test- ing their 468-kilogram (1,032-pound) NEAR As a test of the feasibility of their “faster, bet- spacecraft. On 17 February 1996, they launched the ter, cheaper” initiative, NASA officials had begun spacecraft from the U.S. Air Force Cape Canaveral Low-Cost Innovation in Spaceflight: The Near Earth Asteroid Rendezvous (NEAR) Shoemaker Mission 1 Stamatios Krimigis, head of the Space Department at the Johns Hopkins University Applied Physics Laboratory (right), presents to NASA Administrator Daniel Goldin and Maryland Senator Barbara Mikulski a check representing the cost savings achieved during the design and construction of the NEAR spacecraft. Gary Smith, Director of the Applied Physics Laboratory, stands on the left. (Courtesy of Johns Hopkins University/Applied Physics Laboratory) launch station in Florida. The development pro- NASA’s early efforts to demonstrate the feasibility gram was over, the spacecraft launched and gone. of low-cost spaceflight. Both missions were hugely APL officials totaled the money spent on design, successful. The Pathfinder robot landed on Mars in testing, flight systems, scientific instruments, the summer of 1997. NEAR chased the asteroid prelaunch operations, and project management. To Eros around the solar system for four years, finally the delight of mission advocates, the cost of devel- orbiting the 21-mile-long object in February 2000. oping the NEAR spacecraft totaled $3.6 million less After circling Eros for one year, the renamed than the original estimate. Someone suggested that NEAR-Shoemaker spacecraft touched down on the the project leaders present an oversized, ceremonial asteroid’s surface in February 2001, the first such check to NASA for the money they had saved. landing in the history of spaceflight. Goldin happily accepted it that spring. Much has been written about the management Ten months later, on 4 December 1996, another of the Pathfinder mission, including books by team Delta 2 model 7925 rocket departed from the leaders Brian Muirhead and Donna Shirley.2 Canaveral launch station. It too carried a low-cost Reports on the NEAR spacecraft, the asteroid ren- spacecraft, commissioned by NASA executives but, dezvous, and science results are likewise extensive, in this case, built by workers at JPL. This spacecraft including a book entitled Asteroid Rendezvous: was bound for the planet Mars. Called Mars NEAR Shoemaker’s Adventures at Eros that fea- Pathfinder, the second spacecraft carried in its arms tures illustrations and articles by many of the prin- a small, 22-pound microrover named Sojourner. cipal participants.3 Reports on the management of the NEAR mission are neither as extensive nor as The NEAR and Pathfinder missions were the accessible. This monograph tells the story of the most visible and highly publicized products of NEAR mission from the point of view of the man- 2 Low-Cost Innovation in Spaceflight agement challenges involved in conducting low-cost have predicted a future of cheap and easy space- missions while daily confronting the possibility flight by which means humans and their machines of defeat. would spread into the solar system. The NEAR mis- sion team undertook one of the pioneering efforts The history that follows is divided into four sec- in that regard, producing a spacecraft that tested tions. The first section recounts the origins of the not only scientific theories concerning the forma- expedition and the struggle to get the mission funded tion of the solar system, but also management the- and approved. It explains how a small group of ories on the reduction of cost. people came to believe that an asteroid rendezvous could be conducted as a low-cost mission, a revolu- In the years that followed, enthusiasm for the tionary proposition at the time. Section two con- “faster, better, cheaper” initiative waned. In 1999, centrates on the methods employed to translate the NASA officials lost four of the five “faster, better, low-cost philosophy into a robotic spacecraft that cheaper” missions they attempted to fly that year. actually worked. Attention is given to the team- In 2003, the loss of the Space Shuttle Columbia building techniques that allowed the people organ- caused experts to question the wisdom of applying izing the mission to simultaneously restrain cost, cost-saving techniques to spacecraft on which meet the launch schedule, and reduce risk. In sec- humans fly. The expenses associated with planetary tion three, the management challenges involved in missions rebounded. The “faster, better, cheaper” flying the NEAR spacecraft over the five-year flight phrase disappeared, replaced by a commitment to regime are described. The difficulties were substan- “One NASA,” a new initiative with no major refer- tial, involving the guidance of a low-cost robotic ences to low-cost innovation.5 spacecraft and the coordination of mission teams at three different locations. On the first rendezvous The legacy of the NEAR spacecraft and the attempt with Eros, the little spacecraft missed its Pathfinder mission with which it once competed target, thus requiring another trip around the solar nonetheless remain important to the overall devel- system and significant changes in organizational opment of spaceflight. If humans and their protocols. Finally, section four assesses the “faster, machines enter space on the scale envisioned by better, cheaper”4 initiative and the NEAR mission’s various experts, the movement will not occur with contribution to it.
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