This novel is a work of fiction. Because of the nature of the plot certain real people associated with the U.S. manned space program are referred to in the story by their real names. For the purposes of weaving my story into the fabric of our own history I have replaced some historical personages with fictional characters. In particular, the second American to orbit Earth was Scott Carpenter, not Chuck Jones as portrayed in the novel; and the second man to walk on the Moon was Buzz Aldrin, not Joe Muldoon as portrayed here. All other characters are fictional constructs, in which case any resemblance to any real individual is wholly unintentional and coincidental.

I would like to acknowledge the invaluable help of Simon Bradshaw, Eric Brown, and Calvin Johnson, all of whom read and commented on versions of the manuscript; and the staff at NASA’s Johnson Space Center, Houston, who were extremely generous of their time and energy in support of my research for this book, particularly Eileen Hawley, Paul Dye, Frank Hughes, astronaut Michael Foale, and especially Kent Joosten of JSC’s Solar System Exploration Division, who scrutinized my Mars mission with great attention and care. The assistance of these friends has greatly improved the accuracy of my depiction, and any remaining errors and omissions are my responsibility.

In our history, Americans have not traveled to Mars. But in 1969 the U.S. came as close as it ever has to assembling the will and resources for such a mission. Diagrams in the endpapers show how the mission might have been assembled. In an afterword, for interested readers, I have set out my understanding of the crucial historical points at which America turned away from Mars.

In 1996, we need scientists on Mars, they could have been there a decade ago. My novel may be the closest thing to a history of that lost, alternate universe ever to be written, and I have striven to make it as “true” as possible.

It really would have been like this.

Stephen Baxter

Great Missenden

October 1996

Prologue

This is Ares Launch Control, Jacqueline B. Kennedy Space Center.

We have passed the six-minute mark in our countdown. Now at T minus five minutes fifty-one seconds and counting.

Ares waits ready for launch on Launch Complex 39A.

We are on schedule at the present time for the planned liftoff at thirty-seven minutes past the hour.

Spacecraft test conductor has now completed the status check of his personnel in the control room. All report that they are go for the mission, and this has been reported to the test supervisor.

The test supervisor is now going through additional status checks.

Launch operations manager reports go for launch.

Mission Control at Houston reports that all systems on the Ares orbital booster cluster are also nominal and ready to support the mission. The need to be in plane with the cluster, to enable the docking, is imposing a tight window on today’s launch.