When Blake dared to glance away, down toward the Darwin Sea, he noted with satisfaction the rainbow-spanning palette of lichens and the flowering (however spindly the trees) of the orchards. Even the stubble of last year’s corn crop introduced a touch of color—pale browns—into the vista.
As the sun climbed and, on occasion, the wind died down, it was positively nice outside.
Maybe this weather would last. Observatories on all the moons agreed: the cooling trend had flattened out. PFC levels continued to climb. Someday soon, maybe they would even find the time to check out the moons more thoroughly. Antonio wouldn’t stop asking to go back.
“Andrew,” Blake called. “Good job. Come to a smooth stop. Denise, you’re next.”
And the tractor accelerated.
“Brakes!” Blake yelled. “The left pedal.”
“Sorry,” Andrew said. The tractor slowed.
“Having fun yet?”
Blake whirled around.
Rikki grinned. “What, you didn’t hear my dainty footsteps over the sound of your own screaming?”
“Try teaching ten-and eleven-year-olds to drive. See how calm you are.” And to eager-beaver, beaver-toothed Denise, already groping for the brake release, Blake called, “Not yet! Fasten your seatbelt!”
Rikki said, “Only in Dark years. In standard years, they’re teenagers.”
“And that’s somehow better?” he said, in mock despair.
“You do realize,” Rikki said, “in a few years our daughter will be a teenager, too.”
“And that’s somehow better?” he repeated.
She laughed, pointing.
At the back of his cluster of trainees, Castor and Eve held hands.
The sun warm on his face, Blake considered: a young man’s fancy lightly turning to thoughts of love. And: aren’t those two cute?
And, with the gentle breeze riffling Rikki’s hair, her cheeks aglow in the morning light, her eyes sparkling, Blake decided: I’m not so old, yet, after all.
This world still guarded her secrets, but of two things he was certain.
They had made a home here.
And, on many levels, spring was coming to Dark.
*
After consecutive cycles of anomalous sensor readings, low-level automation roused the Supervisor.
Something had gone awry. Something that mere automation could not undo.
Something the Supervisor itself did not understand.
For years it had labored. To remove excess carbon dioxide. To wring the excess moisture from the atmosphere and deposit the water, as snow and ice, at the poles. To cool and dry a world.
And it had.
All according to plan.
Until now.
While the Supervisor, its preparations complete, had lain dormant, global temperature had ceased its decline. And an exotic gas, nowhere to be found in the Supervisor’s databanks, had appeared, had accumulated, had begun to warm the climate. Nothing in the Supervisor’s programming could explain the changes.
It ran simulations. Fine-tuned hundreds of parameters in its planetary-engineering model. Assessed its options. Simulated anew. Reassessed. Reached a conclusion.
From its perch on the planet’s innermost moon, the Supervisor radioed orders.
A hundred asteroids turned mottled, or striped, or entirely changed shade. And those surfaces continued to change:
—Morphing and shifting in real time as the rocky bodies spun and tumbled.
—Attentive to the distant sun.
—Mindful of the feeble pressure of light itself.
—Delicately harnessing the slightest of differences in pressure between light striking pale and dark surfaces.
All but imperceptibly, orbits began to shift.
Soon after arriving in this solar system, and on a grand scale, by similar means it had redirected asteroids to avoid this planet. The Supervisor’s purpose now was quite different.
A few years hence, the dust hurled into the atmosphere by asteroid impacts would quickly cool things down—
This world had been entrusted to the Supervisor’s care. It would be ready, on schedule, for the arrival of Those Who Come….
*l *
Afterword and Acknowledgments
Did a gamma-ray burst bring on the Ordovician Extinction: the sudden obliteration of more than half the world’s marine species? Not surprisingly, the jury remains out. The evidence is indirect and the events beyond ancient.
Might a modern-day GRB scour Earth’s continents clean of life (including the lives of certain curious primates) and even bring the slaughter far into the oceanic deeps?
Yes. Before that happens, let’s hope humanity has starships.
If we do, will the mechanism be a Dark Energy Drive? That’s harder to know. Dark Energy is less an explanation than a label of convenience for our present state of ignorance. Still, something pushes apart galaxies, causes the accelerating expansion of the universe. Scientists will, someday, learn to understand that something. Who is to say they won’t learn to harness it?
And on, and on, it goes. From cosmic strings to terraforming, from alternative biochemical schemes for life to moving asteroids by applying sunlight pressure, my aim with Dark Secret was to hew to scientific research and foreseeable technology.
Even, in a speculative sense, Those Who Come.
New extrasolar planets are discovered, seemingly, every day. A few of those planets (like Dark) have been Earth-like in size. A few (like Dark) orbit within their sun’s Goldilocks zone, wherein water can remain liquid on a planet’s surface.
Are any of those worlds home to life? Not to anyone’s knowledge. But might there be living worlds Out There? It’s difficult for me to believe otherwise, given how Earthly life fills every conceivable niche—and niches that were once thought inconceivable. High in the stratosphere. Deep in oceanic trenches. In the highly radioactive cooling ponds of nuclear power plants. In arsenic-tainted lakes. Inside rock, deep within the earth’s crust.
None of which is to claim expertise in these (and other) disciplines upon which the novel draws, although I know more now than when I began work on the book. I won’t bore anyone with a list of reference materials. The people who were generous with their expertise—and patient with my many questions—are another matter. Them, I would like to acknowledge.
For many topics astrophysical, I thank Andreas Albrecht, Ph.D. (University of California, Davis) and Neil Cornish, Ph.D. (University of Montana).
Regarding matters of geology, planetary engineering, and orbital mechanics, I thank science journalist—and fellow science-fiction author—Richard A. Lovett, Ph.D.
For feedback on psychological aspects, I thank Jeffrey Barth, Ph.D. (University of Virginia).
Where the novel gets the details right, thank the experts. As always, responsibility for extrapolations, errors, simplifications, and fictional license lies with the author.
Last but certainly not
