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  RED

  ROVER

  Inside the Story of Robotic Space Exploration,

  from Genesis to the Mars Rover Curiosity

  ROGER WIENS

  BASIC BOOKS

  A MEMBER OF THE PERSEUS BOOKS GROUP

  NEW YORK

  Copyright © 2013 by Roger Wiens

  Published by Basic Books,

  A Member of the Perseus Books Group

  All rights reserved. No part of this book may be reproduced in any manner whatsoever without written permission except in the case of brief quotations embodied in critical articles and reviews. For information, address Basic Books, 250 West 57th Street, 15th Floor, New York, NY 10107-1307.

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  All images reprinted with permission.

  Book designed by Linda Mark

  Text set in 11 pt Plantin MT by the Perseus Books Group

  Library of Congress Cataloging-in-Publication Data

  Wiens, Roger.

  Red rover : inside the story of robotic space exploration, from Genesis to the Curiosity rover / Roger Wiens.

  p. cm.

  Includes bibliographical references and index.

  ISBN 978-0-465-05199-1 (e-book)

  1. Space robotics. 2. Roving vehicles (Astronautics)—Instruments.

  3. Curiosity (Spacecraft)—Instruments. 4. Laser-induced breakdown spectroscopy. 5. Mars (Planet)—Exploration. 6. Genesis (Spacecraft)

  7. Wiens, Roger. I. Title.

  TL1097.W54 2013

  629.8'920919—dc23

  2012047020—

  10 9 8 7 6 5 4 3 2 1

  To Gwen,

  who climbed into the gondola and took off with me,

  and said yes, then and ever since

  And

  To all those who have made these adventures possible

  CONTENTS

  Prologue

  PART I: GENESIS

  chapter 1: From Minnesota to the Moon

  chapter 2: The Dawn of an Era

  chapter 3: Mission Selection

  chapter 4: Making Genesis

  chapter 5: Beyond the Moon and Back

  chapter 6: Impact

  chapter 7: Vindication

  PART II: PATH TO MARS

  chapter 8: Lasers and Rovers

  chapter 9: Fire!

  chapter 10: To Mars and Back . . . Almost

  chapter 11: The French Connection

  chapter 12: Ticket to Mars

  chapter 13: New-Instrument Struggles

  chapter 14: Canceled

  chapter 15: Soldiering On

  chapter 16: Rover Motors

  chapter 17: Finishing ChemCam

  chapter 18: On the Rover

  PART III: CURIOSITY

  chapter 19: Coming Together

  chapter 20: Where on Mars?

  chapter 21: Back to the Cape

  chapter 22: Seven Minutes of Terror

  chapter 23: Landing on Mars

  Epilogue

  Acknowledgments

  Further Reading

  Index

  PROLOGUE

  NOVEMBER 26, 2011. IT WAS THE DAY THE CURIOSITY ROVER would launch to Mars; the day we had been anticipating for a decade. In a sense, I had been waiting for this day my whole life.

  As the Sun rose, my family, along with the families of hundreds of other staff members who had participated in the mission, was bused to the Kennedy Space Center. A steady breeze blew toward us from the coast and small clouds scudded overhead, but the launch experts assured us that the weather would not hinder the event. Our observation point was nearly 4 miles from the 210-foot-tall, 350-ton Atlas V rocket, but we saw it clearly in the distance. The metal bleachers filled quickly with hundreds of spectators, who were exiting from dozens of buses. A large countdown clock and a set of loudspeakers stood off to one side. Before us was a lagoon. Beyond the launchpad in the distance was the Atlantic shore. Nearly one whole section of bleachers was crammed with technicians and scientists who had worked on the project that I led for the past eight years—ChemCam, Curiosity’s laser device. My colleagues and their families had come in from all over the United States and France to join the excited crowd. Altogether, more than 10,000 people converged on the Florida coast to watch the launch.

  With forty minutes to go, Charles Bolden, the director of the National Aeronautics and Space Administration (NASA), took the microphone and thanked everyone for their hard work in making this great mission possible. As the countdown passed the four-minute mark, the crowd rose to sing the national anthem. With less than a minute to go, an official-sounding voice came over the loudspeakers with a warning that rocket launches were dangerous and NASA bore no responsibility for injuries to spectators. But the last words were drowned out by the crowd, now counting down the final seconds in unison. As far as I could see, people were on their feet, ready for action.

  “Three . . . two . . . one . . . zero!”

  With that, NASA’s biggest, most ambitious mission to the Red Planet rose from the pad, gained speed, and, to the roar of the crowd, disappeared into the blue sky.

  Space—the final frontier—is being conquered by increasingly sophisticated robots. As you read this, some twenty such craft are trolling through interplanetary space or actively orbiting or driving on another planet or asteroid.

  Over the past fifteen years, robotic space exploration has enjoyed a huge renaissance, starting arguably with the first Mars rover, the puny 23-pound Sojourner. Mechanical creations from Earth are orbiting Mercury, Venus, the Moon, Mars, the asteroid Vesta, Jupiter, and Saturn; others are on their way to Pluto and to land on a comet; and three are on their way out of the solar system. One spacecraft landed on the tiny asteroid Eros, only about 10 miles across, and a European craft landed on Saturn’s largest moon, Titan. Samples have been returned robotically from the Moon, from a comet, from the Sun—in the form of solar wind—and from the asteroid Itokawa. The length and breadth of robotic exploration has been absolutely astounding, and I’ve been lucky enough to experience some of these developments firsthand.

  The Genesis mission—my first venture into space—came near the beginning of the new wave of exploration, launching in 2001. It was the first mission to return from beyond the Moon, yielding samples from the Sun. Genesis was the epitome of NASA’s faster, better, cheaper era; fifteen such missions could be built and flown for the cost of a single Cassini mission (which is orbiting Saturn). Genesis carried only three small instruments and its sample collectors. Genesis failed, and yet it succeeded beyond our wildest expectations.

  By contrast, the Curiosity rover, now on Mars, is by far the biggest—and most complex—vehicle ever sent to drive on another planet. It weighs nearly a ton—the size of a small SUV. Curiosity dwarfs the tiny Sojourner rover, and it is five times as heavy as the older Mars twins, Spirit and Opportunity. To power the vehicle and its ten instruments, NASA turned from solar panels to a nuclear thermal generator, which provides continuous power day and night. Measuring 20 inches in diameter, each of Curiosity’s six aluminum and titanium wheels is nearly as tall as a car tire, but wider. The rocker bogey suspension gives the rover nearly 2 feet of ground clearance, so it is an excellent all-terrain vehicle. The top of Curiosity’s mast stands 7 feet off the ground, giving its stereo cameras a superhuman perspective. And with a robotic arm extending 7 feet, the vehicle is nearly 17 feet long when fully stretched out.*

  Most importantly, Curiosity car
ries over 160 pounds of science payload—it’s a sophisticated laboratory on wheels. It has high-definition, true-color cameras; a laser-interrogation instrument called ChemCam; weather- and radiation-monitoring devices; a neutron adsorption experiment to detect hydrogen; a hand lens; and an alpha particle x-ray spectrometer (APXS) similar to those on previous rovers. The arm, which by itself weighs as much as one previous-generation rover, is equipped with a drill and sample-handling system that can collect and feed samples to the instruments inside the rover. There, samples are x-rayed to determine their crystal structure, and an organic laboratory can sniff for carbon-based molecules.

  The mission’s goal is one that has captured our imagination throughout history: to determine the habitability of the Red Planet, both whether it might have been hospitable enough for microbial life in the past, and whether it could possibly sustain human life in the future.

  We dream about life on Mars because it is the only planet so similar to Earth. Its days are twenty-four hours and forty minutes long; it has nearly half the gravity we have here; its temperatures are the closest of any planet to our own; and it has plenty of water as well as a thin atmosphere. In fact, the air on Mars has more carbon dioxide—the gas that plants breathe—than the Earth’s atmosphere. No wonder the idea of terraforming, or cultivating an oxygen-bearing atmosphere, comes up so frequently, both in science fiction and among real scientists. If humans ever live on another planet, it will definitely be on Mars.

  And if we are the dreamers, the pioneers are the robots. In the early twenty-first century, the most exciting exploration anywhere is being done by robotic spacecraft. As in the expeditions of previous generations—those of Lewis and Clark, Columbus, Magellan, Marco Polo, or Admiral Perry—the goal is to uncover secrets of faraway lands. Although there is no cost in human lives, jobs, reputations, and scientific discoveries are certainly at stake. This is risky but glorious business.

  This book reveals the ups and downs of this exciting new era of robotic space exploration through an account of my experiences working on some of the most fascinating robotic projects of the past decade. With the spectacular crash of Genesis, the exhilarating flight of Curiosity, and all that came in between, I have experienced the thrill of victory as well as the agony of defeat. I never expected to make a career of the most interesting and fun things I could imagine—inventing and flying gadgets to explore outer space. But it happened, and that is the unlikely part of this story. What follows is my small part in the history of space exploration. This is the story of those missions through my own eyes.

  *The arm reaches 2.2 meters. When it is stretched out, the whole vehicle is 5.2 meters long. Its wheel diameter is 50 centimeters, and the vehicle weighs 900 kilograms, 75 kilograms of which are scientific instruments.

  PART I

  GENESIS

  chapter

  one

  FROM MINNESOTA TO THE MOON

  JANUARY 1990. IT WAS A COLD, RAINY DAY IN SOUTHERN California. I drove up from my home of two years in San Diego for a job interview at the California Institute of Technology. The freeway was making me nervous. I had only driven on such a busy freeway once or twice before in my life. As I made my way into Pasadena, my mind flashed back to my childhood days in western Minnesota. I remembered a comment by a classmate who had said that, at Caltech, everyone was a genius. I wondered at the time what it would be like to be at such a place, surrounded by the smartest people in the world. Now I would find out.

  After parking the car and locating the building, I climbed a set of stone tile steps under the turquoise dome that adorned the Spanish-style geology building; stepped into the tall, dimly lit hallway; and knocked on the first door. A short professor with a round face and balding crown answered it and invited me in. Near the doorway, I couldn’t help noticing an early 1980s TRS-80—one of the first personal computers, now well past its normal lifetime. The rest of the room was ringed with shelves stacked with books and piles of papers.

  Don Burnett, professor of geochemistry, sat down opposite me, half-nodded in a gesture with which I was to become familiar, and said, “Well, basically, you can have the job.”

  “I’ll take it,” I returned. It was about the shortest job interview ever.

  The job in question was to study the feasibility of a new space experiment, something I had never done before. Don’s idea was to collect and return solar particles to Earth to learn more about the Sun’s composition. A steady stream of atoms was known to flow outward from the Sun. These had first been observed in the early 1960s. It was relatively easy to build instruments that would detect their abundance, speed, and a few other properties. However, it was notoriously difficult to measure their composition. Don believed that instead of analyzing these atoms with an instrument on board a spacecraft, the job would require a sample-return mission.

  I had met Don a couple of years earlier, and we had discussed the prospects of working together at that time. But, when I finished my PhD, I was not at all convinced that I should go into the space exploration business. Nor was I optimistic that there would be a future working on Don’s project. So I had decided on another job instead. Now my other work had come to an abrupt end, and other than checking with Don, I had absolutely no leads. We spent about two more hours together talking about the work ahead. Don had led one experiment on the Moon during the Apollo missions, but, like me, he had no experience in robotic spacecraft. We would be learning together.

  As my Chevy Nova crept along in the heavy traffic back toward San Diego, I mused on how I had ended up here. My interests in space exploration had always been strong, and as a kid I had dreamed of becoming an inventor someday. But it was just a dream. After all, I had grown up in western Minnesota in a Mennonite farming community. Coming from such a place, I didn’t really believe that my childhood dreams—ideas of rockets and space exploration—could come true.

  My brother and I were born into the Space Age around the time of Sputnik and the Mercury program. I was two years younger than Doug, and we did everything together. We were a little different from the other boys in our community. The late 1960s were, for us, all about rockets and astronomy. We started building model rockets after seeing an advertisement in a Boys’ Life magazine at the local library. Our parents let us order a starter kit, and I experienced my first launch as a third grader. Even though the parachute got caught in a tree, it was the beginning of a love affair with anything made to go skyward. Over the next five years we built a small arsenal of rockets: one-, two-, and three-stage models and replicas of sounding rockets, ballistic missiles, and launch vehicles used by the astronauts. Our collection included models with names like Aerobee, Avenger, Alpha, Farside, Sky Hook, Mars Snooper, and Cherokee; a replica of the Mercury Redstone that propelled the first American into space; and a fat, ugly model called Big Bertha.

  An old kitchen table with a red Formica top served as our workbench. The rocket kits were reasonably easy to assemble: cut the fins out of thin sheets of balsa wood, glue them on the body, and, with a few more steps, one could be done. However, Doug, our quality control engineer, insisted that each fin have at least seven coats of sealer, on which we used progressively finer sandpaper. This was only after the leading edge of each fin was meticulously shaped to the most aerodynamic form. Moreover, our fins were not simply slapped on; multiple coats of glue were used to provide a smooth, strong transition between body and fin. Paint schemes were carefully considered, decals procured and placed. We also applied thin lines of colored tape, cut with utmost care using a razor blade.

  As we graduated to more powerful models, we ended up losing a few, especially the two- and three-stagers, because they flew out of sight. The solution was to assemble a radio beacon kit. It contained a tiny battery and a few radio components, which we soldered in place on a tiny circuit board. When powered on, the unit transmitted radio pulses to our walkie-talkies.

  Our rocketry activities took many forms. We combined the hobby with photography and won a priz
e in a contest put on by the model rocket company. We built a camera to fit on a model rocket and took aerial pictures of the neighborhood and town, using film developed in a makeshift darkroom in our basement.

  On occasion we launched explosives. We watched the fireworks high above our neighborhood at night and learned that gasoline-soaked tissue paper floats a long way while it burns.

  There is no doubt that our hobby was inspired by NASA’s Apollo program, aimed at placing humans on the Moon before the end of the 1960s, as articulated by President Kennedy in a 1961 speech before a joint session of Congress. Doug and I watched every astronaut launch faithfully from the time our family owned a television. A particularly strong memory for me was the Christmas launch of Apollo 8—the first mission to the Moon.

  Apollo 8, launched December 21, 1968, was nearly the first US-manned flight in two years. A fatal fire during a launch rehearsal in 1967 had set the program back by many months while systems were reviewed and redesigned. It was widely feared that the Soviet Union would leap ahead during this hiatus. After a test flight of the Apollo capsule (Apollo 7) in Earth orbit in October 1968, NASA made a very bold move to make up lost time. It announced that it would send Apollo 8, the first manned flight with the huge Saturn V rocket, directly to the Moon without any further testing in Earth orbit. This mission might leapfrog the United States ahead in the race to the Moon.

  As young boys growing up in a small town we were only vaguely aware of the turbulent events of the 1960s, but we understood that a restrictive totalitarian state intended to show that it was superior to one that allowed its people many freedoms, and that this launch was to play a key part in the space race. It could put the United States firmly ahead or, due to its risky nature, it could very well end in disaster. Many of the unmanned probes sent into interplanetary space had veered off course and failed; the risks of human space flight were very real.