It is important to note that carbon dioxide, with its molecular weight of 44, is heavier than oxygen and nitrogen. When there are windstorms up on the surface of Mars, the winds are often made up of carbon dioxide that is evaporating from the polar caps. The airflow can stream down Getout Slope, get denser as it moves into the higher pressure regions near the bottom of Dugout Crater, and puddle in low-lying areas, displacing the air with the 48% oxygen that you need to breathe. Your turboexchanger and filters may be working just fine, but no oxygen in—no oxygen out. As you move around outside, keep a watch on the oxygen-level indicator, and don't commit yourself to a fast descent into a depression unless you are carrying an oxygen bottle in addition to your turbomask.
FIRES
The other reason we need carbon dioxide in the atmosphere is to keep from burning the place up. We could have had the Lineups generate us a pure oxygen-nitrogen atmosphere with almost no carbon dioxide in it. Unfortunately, the amount of nitrogen readily available in the ice caps (as frozen ammonia clathrates) was limited. The total nitrogen partial pressure that could be generated was 36 millibars at Martian "sea level" and 67 millibars down at the bottom of Dugout Crater. Combining that with the present 240 millibars of oxygen in Dugout would have produced 307 millibars total down at the bottom of Dugout. This pressure level would be high enough that space suits would not be needed and with sufficient oxygen partial pressure and no carbon dioxide, no turbomasks would be needed.
Unfortunately, an atmosphere of almost all oxygen may be fine for breathing, but it can be deadly if a spark or match flashes. Especially since we wanted to put some methane in the atmosphere to act as a greenhouse gas to warm the place up. An atmosphere made up of oxygen and methane would be fine—until someone lit a match! We need some nonflammable gas to keep the oxygen percentage down. Unfortunately, the only thing available was carbon dioxide.
With the present mixture of 48% oxygen, 35% carbon dioxide, 13% nitrogen, and 3% methane, the atmosphere won't burn all by itself, since the flammability range for methane is over 5%. The relative amount of oxygen is quite high, however, more than twice that on Earth. Although the lower air pressure helps keep fires down, you musf be careful about matches, sparks, and open fires. We have invested too much in our trees to lose them in a forest fire.
PLACES
There are lots of places to go on Mars. After all, Mars has the same amount of land area as the dry land surface area on Earth. Unfortunately, there aren't too many places to go that have people. Here is a list of the main cities, and the camps that have shelters and life-support facilities, but no permanent occupants.
CITIES:
AUGUSTUS (aka Dugout) [-39 S 303 W -14 km, pop. 4500]. Capital of Mars. On a crescent-shaped terrace 2 km above Splash Lake at the bottom of Dugout Crater. There are a number of suburbs of Augustus (such as Halfway Terrace at -10 km) at each of the terraced levels at increasing elevations until we get to Breakout Base at - 4 km in the Hellas Plains (aka Hell's Flats) at the top of Getout Slope. Over the decades, Augustus will move upward and finally disperse as Dugout Crater fills up and starts to spread out into Hellas Plains to form Hellas Sea. The debris from Dugout Crater covered over the original USSR base Novosibirsk that was nearby.
MUTCHVILLE [+24 N 45 W -3.5 km alt., pop. 250]. City in the middle of Chryse Plains, the second lowest basin on Mars. One of the spaceports of Mars. The altitude of the basin is low enough at -3.5 km, that the post-Splat air pressure of 28% Earth pressure is sufficient for people to operate outside without pressure suits—just a turbomask. Mutch Memorial is 100 km away to the southwest. Primary activity of the personnel is studying shorelines of the ancient Martian Boreal Ocean. Duplicate samples of all Mars-adapted plants are also kept here in case some catastrophe hits the nurseries at Augustus.
ISIDIS (aka Insidious) [+14 N 272 W -1 km alt., pop. 200]. A small city in the third lowest basin on Mars. The air pressure, however, is only one-quarter of Earth pressure. Unless you are an old-timer and know what you are doing, don't assume that your skin will serve as an adequate space suit and wear a pressure suit outside. (Most old-timers got to be old-timers by wearing a pressure suit even when they didn't really have to.) A base for exploring the northeastern portion of Mars.
OLYMPUS [+14 N 130 W +2.5 km, pop 200]. Previously USSR Novomoskovsk and original capital city of Mars. At the base of Olympus Mons just below the southeast scarps. One of the spaceports for Mars. There are a number of camps around and on Olympus Mons that are attached to Olympus city. About 100 km due north of Olympus city is one of the two near vertical cable lifts up onto the Olympus Mons ramparts. This one goes straight up almost 5 kilometers. The cable-lift from the northwest campsite goes up almost 8 kilometers. Saves a lot of climbing. (The cable-lifts only put you at 10 kilometers, however. It is 17 more kilometers to the top of Olympus Mons!)
MELAS [-10 S 73 W +2.5 km, pop. 200]. Previously USSR Novokiev. At the bottom of Valles Marineris in the Melas Chasma. Low altitude base for exploring the western end of Valles Marineris. Very close to Sinai Springs.
BOREAL BASE (aka Boring) [+79 N 48 W 0 km, pop. 150]. Previously USSR Novomurmansk. Right at entrance to Chasma Boreal. Main scientific base for exploration of the North Pole of Mars.
AUSTRAL CANYON (aka Bottom) [-84 S 262 W 0 km, pop. 150]. Previously USSR Novovladivostok: Deep in Chasma Austral. Main scientific base for exploration of the South Pole of Mars.
HALFWAY TERRACE [-41 S 303 W -10 km alt., pop. 1000]. Halfway is one of the cooler, and therefore popular, suburbs of Augustus that is halfway up Get-out Slope, 6 km up and 100 km south of Splash Lake.
HELLAS BASE (aka Breakout) [-42 S 303 W -4 km alt., pop. 250]. Breakout is at the top of Getout Slope, 12 km up and 200 km south of Splash Lake. Going from Splash Lake to Breakout is like climbing an inside-out Pavonis Mons. One of the spaceports for Mars.
SINAI SPRINGS [-8 S 84 W 8 km alt., pop. 100]. Continuously occupied base despite high altitude. Major activities consist of water engineering projects trying to tap the large water reserves and the potential energy difference between the top and bottom of the nearby cliffs into Valles Marineris.
NORMALLY UNOCCUPIED CAMPS:
THARSIS SADDLE [-4 S 117 W +10 km alt.]. In the flat spot between Arsia Mons and Pavonis Mons. Originally set up as a base camp to explore the three mountains on the Tharsis Ridge.
ELYSIUM SADDLE [+29 N 211 W +5 km alt.]. Formerly USSR Novoleningrad. In the flat spot between Elysium Mons and Hecates Tholus. Originally set up as a base to explore the Elysium Ridge.
SOLIS LACUS [-26 S 80 W +6.5 km alt.]. Formerly USSR Novobaku. Early radar studies of Mars by Earth seemed to indicate this region produced specular microwave reflections, as if liquid water were on or near the surface. The USSR set up a base here to look for the water. Water-oriented activities were later shifted to Sinai Springs and this camp abandoned.
HELLESPONTUS (aka Hellsbridge) [-30 S 315 W + 3.5 km alt.]. Another site where Earth radar detected liquid water.
MARINER LAKE (aka Drainhole) [-7 S 36 W -2 km alt.]. Lowest part of Mariner Valley. Post-Splat air pressure of 26% Earth pressure and average summer temperature above freezing, are enough to allow pools of water to form in the summer. (I have some lakefront property for sale.) Base is used during summer for scientific studies of permafrost melting, valley dynamics, and lake formation.
MUTCH MEMORIAL (Viking 1 Lander) [+22 N 48 W -1.5 km alt.]. A must for every tourist to Mars. 100 km southwest of Mutchville.
VIKING 2 LANDER [+48 N 226 W -1.5 km alt.]. A long way from everywhere.
The End
About the Author
Dr. Robert L. Forward obtained his Ph.D. from the University of Maryland, where for his thesis he built the world's first bar gravitational radiation detector—now in the Smithsonian. For thirty-one years, he worked at the Hughes Research Labs in Malibu, California. There he constructed and operated the world's first laser gravitational radiation detector and invented the rotating gravitational mass sensor.
His current work with the United States Air Force Astronautics Lab allows him to explore the forefront of physics and engineering. Dr. Forward writes prodigiously, both in fact and fiction.
* * * * * *
Book information
Sale of this book without a front cover may be unauthorized. If this book is coverless, it may have been reported to the publisher as "unsold or destroyed" and neither the author nor the publisher may have received payment for it.
A Del Rey Book
Published by Ballantine Books
Copyright © 1991 by Robert L. Forward
All rights reserved under International and Pan-American Copyright Conventions. Published in the United States by Ballantine Books, a division of Random House, Inc., New York, and simultaneously in Canada by Random House of Canada Limited, Toronto.
Library of Congress Catalog Card Number: 90-24636
ISBN 0-345-37772-9
Manufactured in the United States of America
First Hardcover Edition: June 1991 First Mass
Market Edition: July 1992
To Martha and Eve—
for willingly joining me in the not-so-idyll wildernesses.
ACKNOWLEDGMENTS
Any hard science fiction novel must necessarily draw on many sources of factual information. That information has been laboriously gathered or deduced by literally armies of researchers—scientific, engineering, and literary—scattered over centuries of time. A few of the specific technical publications that I consulted the most in writing this novel are listed in the bibliography. In addition, there are many people who gave me novel ideas, valuable insight, or factual information that contributed significantly (sometimes by showing me it couldn't be done that way) to my fictitious regeneration of a Mars where rainbows could form.
When the story follows the reader's personal version of the "known scientific facts", the people I acknowledge below can take most of the credit. When the science unrolled in the story begins to raise doubts in the reader's mind, then it is my responsibility. Either: (1) I goofed in my interpretation of the science, (2) my interpretation of the "known scientific facts" does not agree with the reader's interpretation, (3) or I followed the Final Law of Storytelling: "Never let the facts get in the way of a good story."
With this understanding, I would like to acknowledge the help of the following people: Penelope J. Boston, Robert D. Forward, Joel C. Sercel, Paul A. Penzo, Robert M. Powers, James E. Oberg, Carol R. Stoker, Thomas R. Meyer, A. W. Gerhard Kunze, Alex and Phyllis Eisenstein, John Eades, Edward (Ned) J. Britt, H. Jay Melosh, Tom Gangale, and Lester del Rey.
Then, of course, there is Robert A. Heinlein. Without the early inspiration of his books, I probably would not have been a space scientist, much less a science fiction writer. There is nothing that I write or do that doesn't have his touch somewhere in it. Some readers, midway through this book, might have a sense of déjà vu—that they have read something like this before. They have—in "Concerning Stories Never Written", a postscript to Heinlein's Revolt in 2100. I was concerned when my outline for this book showed strong resemblances to the plot concepts in that postscript, and wrote to Robert. But he called me up and encouraged me to go ahead.
The same sense of déjà vu also happened to readers of my first book, Dragon's Egg, where my story of aliens living in a high-gravity world reminded readers of Hal Clement's classic novel, Mission of Gravity. (Sometimes I get the feeling that I'm the "Linda Ronstadt" of science fiction, dishing out old classics in modernized arrangements.)
My apologies to real Congressional Medal of Honor winners. I know that what Alexander Armstrong did during the battle for Mars doesn't qualify him to receive the medal. But then, he had full control of the communications links back to Earth ... and somehow the real story managed to get improved upon in the telling ...
My special thanks to the staff of the Mariner/Viking Image Library at JPL and the Mariner and Viking teams for the images that allowed my imagination to take you on a vicarious visit to the surface of a distant red spot of light in the sky.
BIBLIOGRAPHY
Boston, Penelope J., ed. The Case for Mars. American Astronautical Society Science and Technology Series, Vol. 57 (1984). Proceedings of the Case for Mars Conference, Boulder, Colorado (29 April-2 May 1981). Published for AAS by Univelt, Inc., P.O. Box 28130, San Diego, CA 92128.
Carr, Michael H. The Surface of Mars. New Haven: Yale University Press, 1981.
McKay, Christopher P. "Terraforming Mars." Journal of the British Interplanetary Society 35 (1982): 427-433.
McKay, Christopher P., ed. The Case for Mars II. American Astronautical Society Science and Technology Series, Vol. 62 (1985). Proceedings of the Second Case for Mars Conference, Boulder, Colorado (10-14 July 1984). Published for AAS by Univelt, Inc., P.O. Box 28130, San Diego, CA 92128.
MECA. Abstracts of papers presented at the Symposium on Mars: Evolution of its Climate and Atmosphere, Washington, DC (17-19 July 1986), LPI Contribution 599. Compiled by the Lunar and Planetary Institute, 3303 NASA Road One, Houston, TX 77058.
Oberg, James Edward. New Earths: Transforming Other Planets for Humanity. Harrisburg: Stackpole Books, 1982.
Pollack, James B. "Climatic Change on the Terrestrial Planets." Icarus 37 (1979): 479-553.
Powers, Robert M. Mars: Our Future on the Red Planet. Boston: Houghton Mifflin Company, 1986.
Sagan, Carl, and Mullen, George. "Earth and Mars: Evolution of Atmospheres and Surface Temperatures." Science 111 (7 July 1972): 52-56.
Spitzer, Cary R., ed., and the Viking Orbiter Imaging Team. Viking Orbiter Views of Mars. NASA SP-441. Science and Technical Information Branch, NASA, Washington, DC (1980). [Obtain from US Government Printing Office, Washington, DC 20402.]
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