Red Rover
Page 23
ChemCam’s turn-on occurred on sol 13. After the mast was deployed, the science team imaged the surroundings so we could select a rock target for ChemCam. The rover operators made sure they could point the mast with confidence, and then we received the green light to fire the first laser shots. The commands were sent up to Mars, and we caught some sleep while the rover carried them out. Thirteen was to be our lucky number. I arrived early the next morning, as the sol was drawing to a close on Mars. The data were not supposed to be downlinked for a couple of hours, according to the information we had about the timing of the satellite passes over the rover. However, shortly after we arrived, Dot DeLapp, our data specialist, jumped up, exclaiming that the spectra had already been transmitted to Earth. As I transferred the data from the host server to my laptop, Sylvestre and a couple of French colleagues arrived. I hit the “display spectrum” button, and a beautiful set of peaks appeared on the screen. The signal was strong and clear—the first LIBS spectrum from another planet. The rest of the day was a blur of congratulations, talking to media representatives and team members about what we were seeing, and planning for the next activities. At the science assessment meeting, the French team members were ready with enough bottles of champagne for everyone. More celebrations followed.
ChemCam’s first target, which looked like a familiar basalt, gave way over the next dozen sols to a composition of igneous rocks that was somewhat different from what the MERs had observed, reminding us that we don’t yet know much about our companion planet. But the sedimentary rocks we were hoping to see did not disappoint. The first few sols of driving revealed that Curiosity was traversing an ancient riverbed. There were rounded pebbles—at first only a few among the gravel strewn across the surface. Then we discovered a conglomerate rock—a cemented mass of smaller rocks—shedding rounded pebbles into a pile just below it. These objects could only have been rounded by the action of running water or waves on a shoreline.
The sense of excitement over the Gale landing site grew steadily among the science team. It began with the early sol images of the huge, 16,000 foot mountain just a few miles away. Nothing even remotely like it had been encountered on any previous missions. Then there were the unexpected rock compositions and finally the conglomerates. Scientists who had complained earlier that Gale Crater was a poor landing site choice were now clearly excited with the findings, spending much more time at JPL than they had originally planned. They realized that Gale offered not only the mountain but also the depths of the crater as fascinating study sites; both were highly relevant to the goal of understanding Mars’ habitability.
The team is now preparing for remote operations. Soon our interactions and commands to the rover will be communicated remotely from various points on Earth, by telephone and in cyberspace. Life will return to normal in at least some respects, and our days will no longer be bound by Mars time. But we will remain Mars explorers for as long as Curiosity lasts, whether that be just one sol, in the event of an accident, or fifteen years.
From the vantage of sol 74, it seems incredible that everything has gone so smoothly up to this point. Of course we encountered some bumps: at first we feared that gravel thrown up by the Sky Crane thrusters might have damaged parts of the rover; one of the two wind sensors located halfway up the mast did not respond, and there appeared to be a dent in a piece of critical hardware on the deck. Extra care was taken in deploying the MaHLI imager on the end of the arm after hints of gravel were seen around edges of its deployable lens cover. Ultimately, except for the one sensor, everything was fine. All of our hard work and preparation had paid off—we had a working robot on Mars.
As Curiosity made its way to the Glenelg triple point and old questions began to be answered, new questions arose to take their place: What else was here besides an ancient riverbed? Would we find evaporites—salt precipitates that remain when a lake dries up? Would we find clay beds hidden from the view of orbital instruments by the ubiquitous dust? Peeking over the rise and down to Glenelg just this week, it appears that volcanic rocks might predominate, though it is a bit early to be sure. We see ropey textures and cracks that could have formed when the lava cooled. In our science discussions, vulcanologists have been juxtaposing pictures of messy-looking Hawaiian lava flows with the Curiosity Mastcam images. What would lava be doing in the bottom of an ancient lake? We are reminded of Gusev Crater—the landing site of Spirit in 2004. It was supposed to be a lake, but all that could be found in the first year there was basalt from a lava pond. But perhaps the history of Gale was more complicated than we imagined. Some people are suggesting that these shapes include pillow lava, which forms exclusively underwater. Could water and lava have coexisted here?
And what does it all mean for habitability? With Curiosity we will find out.
The beautiful but deserted terrain of Mars evokes the feeling of an abandoned mansion. It seems that everything is there except the occupants. The same Sun rises and sets. A large mountain is to the east. Pebbles crunch under the wheels. The wind blows the sand grains ever so slightly from day to day. But no one is there. Maybe that will change someday.
ACKNOWLEDGMENTS
THE ADVENTURES DESCRIBED HERE RESULTED FROM THE WORK of thousands of people, many of whom have poured their heart and soul into these missions, working long hours and making many sacrifices. Many of these people deserve every bit as much credit as I. More than 3,000 people worked on the Curiosity rover at some point along its development at JPL alone. Of my instrument, ChemCam, we counted more than 180 people who were involved in a significant way. Each major NASA mission selection involves over 100 proposal reviewers, often taking several weeks out of each person’s life. I am truly grateful to all those who have made these missions possible.
A special acknowledgment goes to the leaders of these missions: Pete Theisinger, Richard Cook, Chet Sasaki, Don Sweetnam, Jeff Simmonds, and Ed Miller on the spacecraft and payload side, and Don Burnett, Ed Stolper, and John Grotzinger on the science side. They are amazing and yet personable leaders. Regarding the subject of our explorations, I thank God for a universe that continues to amaze us with each new mission and each new decade. Having seen the discoveries of five decades, I wonder what we might be privileged to find in the next five—new physical dimensions, intelligent life elsewhere in the universe, or what? I only know it will be something unexpected.
Likewise, I am grateful to my family for supporting me in both the adventure of space exploration and in writing this book. Gwen has rarely complained of being a “space widow” but she truly has been one for weeks at a time. I am fortunate that she has been a vicarious adventurer with me. My sons, Carson and Isaac, saw less of their dad at Cub Scouts and Boy Scouts than many of the others, and I am thankful that they have let me go do my thing. Of course, I’m thankful that my parents encouraged us to go out from the little town of Mountain Lake into the big world of science. My brother, Douglas, had a special influence on me in that regard.
I am also thankful to many individuals at Los Alamos National Laboratory for encouraging me to write about our adventures.
This book is not truly my work—it had many editors and critics, including Susan Bronkhorst, Gwen and Carson Wiens, Sandra and Marjorie Knight, and lastly, those who publish books for a living: Felicia Eth, Tisse Takagi, Sandra Beris, Kathy Streckfus, and others at Basic Books. Each person added to the richness of this work.
FURTHER READING
Following are a number of books on Mars and on robotic exploration.
Managing Martians, by Donna Shirley, Broadway Books, 1998, 277 pages. This book was written by the JPL manager of the first Mars rover mission, which landed a toy-sized rover that lasted two months.
A Traveler’s Guide to Mars, by William K. Hartmann, Workman Publishing Company, 2003, 450 pages. Hartmann gives the reader a tour of Mars, focusing on a number of diverse locations and why they are interesting. A number of sidebars provide additional human-interest details.
Roving Mars: Spir
it, Opportunity, and the Exploration of the Red Planet, by Steve Squyres, Hyperion, 2005, 422 pages. Steve was the project scientist for the second Mars rover mission. In this book he describes this JPL project and the first several months on Mars.
Space Invaders: How Robotic Spacecraft Explore the Solar System, by Michael van Pelt, Springer, 2006, 328 pages. The author describes robotic spacecraft from the ground up, as well as their destinations.
Postcards from Mars, by Jim Bell, Plume (Penguin), 2006, 196 pages. Bell, who was in charge of the cameras for the Mars Exploration Rovers, provides a picture book of the mission. This book contains relatively little narrative and relies instead on many images to tell the story.
Distant Worlds: Milestones in Planetary Exploration, by Peter Bond, Springer, 2007, 335 pages. This is both a reference and a public-interest book on the planets and the robotic spacecraft that have visited them.
Mars 3-D: A Rover’s-Eye View of the Red Planet, by Jim Bell, Sterling, 2008, 160 pages. This work provides 120 3D and color images taken by the Spirit and Opportunity rovers.
Landscapes of Mars: A Visual Tour, by Gregory L. Vogt, Springer, 2008, 138 pages. This book selects various locations to describe and includes many images.
A Passion for Mars: Intrepid Explorers of the Red Planet, by Andrew Chaikin, Abrams, 2008, 280 pages. This book is based on extensive interviews of people active in Mars exploration prior to and at the time of writing.
The Scientific Exploration of Mars, by Fredric W. Taylor, Cambridge University Press, 2010, 362 pages. This is a reference book but interesting enough for popular appeal. It includes discussion of searching for life on Mars and on plans for human habitation.
Martian Summer, by Andrew Kessler, Pegasus Books, 2011, 341 pages. Kessler, a journalist, embedded himself in the Phoenix Mars lander team in 2007 to write about this mission, which lasted about ninety days.
Exploring Mars: Chronicles from a Decade of Discovery, by Scott Hubbard, University of Arizona Press, 2012, 224 pages. This book explores the politics behind the decade from 2000 to 2010, written by one of the administrators who helped make the Mars missions happen.
Destination Mars: New Explorations of the Red Planet, by Rod Pyle, Prometheus Books, 2012, 348 pages. The author interviewed many of the people active in Mars exploration and put together a very colorful description of the Mars missions to date and the outlook for the future.
Robotic Exploration of the Solar System, Part 1: The Golden Age, 1957–1982, by Paolo Ulivi and David M. Harland, Praxis, 2007, 600 pages.
Robotic Exploration of the Solar System, Part 2: Hiatus and Renewal, 1983–1996, by Paolo Ulivi and David M. Harland, Praxis, 2008, 550 pages.
Robotic Exploration of the Solar System, Part 3: The Modern Era, 1997–2009, by Paolo Ulivi and David M. Harland, Praxis, 2012, 400 pages. These three volumes are a systematic history of robotic spacecraft development and exploration.
INDEX
References to the photo gallery are set within parentheses and denoted by ins. img. followed by a number indicating order of appearance.
Accelerometers, 60
Aerogel collectors, 87
Aerogel, described, 86
Alpha-particle x-ray spectrometer (APXS), 109–110, 160, 171, 212
Aluminum, 17, 162, 174
American Association of Variable Star Observers, 9
Ames Research Center, 76, 77, 101, 169
Anders, William, 7–8
Antenna motor, 146
Apollo 7 mission, 6
Apollo 8 mission, 6, 7–8
Apollo 11 mission, 17, 71–72
Apollo 16 mission, 17
Apollo missions, 4
aim of, 6
capsules used for, 144
cost of, 20
costs since, 15
and Earth-based laser systems, 71–72
first of, to the moon, as a manned mission, 7–8
first planned return of a capsule since, 30, 47
laser altimeters on, 72
lunar soil from, 17
next logical step following, 87
as sample-return missions, 18, 20
and XRD instruments, 169
Apollo-Soyuz project, 95–96
Argonne National Laboratory, 27, 71
Arizona State University, 85
Arm motors, 145–146
Arm, rover unit, 75, 98, 99, 107, 109, 110, (ins. img. 15), 127, 142, 145, 162, 164, 171, 175, 195, 196, 212, 214
Arvidson, Ray, 77, 177
Assembly, test, and launch operations (ATLO) phase, 139–140, 146–147
Asteroids, 14
Atlantis, space shuttle, 188
Atlas rockets, 187–188
Atlas V, 187, 188, 191, 201
Baldonado, Juan, (ins. img. 3)
Balloon tanks, 187
Barefield, James, 174
Barraclough, Bruce, 35–36, 38, (ins. img. 6), 130, 134, 186, 206
Basalts, 173–174, 213, 214
Baumgartner, Eric, 75
Bender, Steve, 153, 157–158, 162
Bernardin, John, 126
Beryllium, 126, 138
Bibring, Jean-Pierre, 180–183
Blake, Dave, 133, 169–170
Blaney, Diana, 106, 141
Boeing, 24, 96
Bolden, Charles, 209
Borman, Frank, 8
Bradbury Landing Station, (ins. img. 16), 211
Bridges, Nathan, 101
Burnett, Don, 4, 16–17, 18, 19, 21, 24, 25, 27, 33, 35, 47, 49, 57, 59
Calcium, 174, 175
California Institute of Technology (Caltech), 3, 12, 13, 18, 26, 73, 85, 182
Caltech Division of Geology and Planetary Sciences, 26, 27, 172
Canada, 107, 171, 204
Cape Canaveral
celestial mechanics involved in launching from, 41
first major launch at, since last shuttle launch, 188
launch of Genesis at, 185
space shuttle at, 45
Capsule
Curiosity, (ins. img. 12), 161, 164, 188, 189, 193, 194, 203, 206, 208, 210, 217
Genesis, 30, 35, 39, 47, 48, 49, 51, 52–53, 54, 55, 56, 57, 60, (ins. img. 1, 2), 193
Mars Science Laboratory, 144, 145
SCIM, 93
Stardust, 60
Capsules
on the Apollo missions, 6, 18, 30, 144
for Mars Exploration Rovers, 145
reentry, 18, 19, 20, 23, 24, 47, 51, 52, 53
Carbon, 47, 64, 73, 175
Carbon dioxide, 146
Carbonates, 174, 175, 176
Cassini, mission to Saturn, 14, 160
Challenger disaster, 13, 92
Charge-coupled devices (CCDs), issues with, as detectors, 117–120, 137–138, 151, 152–153, 154, 155
ChemCam
advantage held by, 106
ATLO phase and, 139–140
box protecting, on the Curiosity rover, (ins. img. 15)
and budget issues, 110, 126, 130
cancellation of, 130–134, 135, 160, 172, 191, 192
CCD detectors for, issues with, 117–120, 137–138, 151, 152–153, 154, 155
challenge of interfacing, with the rover, 112–113
cold-temperature communication problem, 151
continued funding of, 135
cost review, 140–141
cost-cutting actions to stop cancellation of, 133, 135, 138, 152
deciding on naming LIBS instrument project as, 102
delivery date to JPL, 138, 139, 140
delivery review and performance of, 159–160
design review, 116
electrical cable damaging parts in, effect of, 134–135
French collaboration on, 102, 103, 108, 116–117, 122–123, 126, 129, 130, 131, 132, 133, 134, 138, 139, 159, 160, 161
halfway into developing, euphoria wearing off during, 121–122
initial turn-on and electrical checkout after landing, 210
installation of, on Curiosity, 158,
161
instruments complementing, 109–110
laser accident and work on, 106
laser instrument testing, (ins. img. 6), 129
letter-writing campaign to save, 132, 135
likelihood of success of, presentations on, 191–193
Mars landing-site meetings and, 177, 181
mast and voltage issues, 126
and the MSL launch delay, 148
and the MSLICE program, 195
nearly finishing the prototype for, 124
new detectors for, 120, 153, 155, 156
optical fiber issues, 113–116, 120–121, 122, 126, 138
optical lens design and, 156, 157–158
potential disaster scenarios involving, and impact, 193–194
projected performance of, review of, 115–116
proposal for, submission of, 102–103
radiation and, 154
rebuilt demux for, 156, 157
restoring full funding of, 141
selection of, as a MSL rover instrument, 108–109
as a sentry, 109
“shake and bake” tests involving, 138, 156, 163–164
and simulations using a mirror, 123, (ins. img. 7)
Slow Motion Field Test and, 173, 174
spark produced by the laser from, (ins. img. 8)
team members of, gathering to watch Curiosity’s landing, 206
temperature issues facing, 151, 154, 155–156
testing, after installation on Curiosity, 161–164
total cost of, 160
turn-on and testing after landing, 212–213
weight issue involving, 126
whole team for operating, 196, 205
See also Laser-induced breakdown spectroscopy (LIBS)
CheMin XRD instrument, 133, 169, 170, 212