6

Earth was once more a ball of magma, everywhere molten, reduced to a primordial smoothness, as it had been when young.

But the planet was expanding.

The unified-force energy released in its core and mantle was overcoming the controlling pull of its gravity. But the expansion was uneven, and bolides, giant chunks of rock, burst out of the churning surface and traced long, glowing curves around the world.

New cracks appeared in the magma ocean, wide fissures filling up with rivers of plasma light, white and yellow and green. As if emerging from a rocky egg, the plasma ball broke open the last shells of Earth, the remnants of the mantle and asthenosphere, molten rock and iron, and hurled out giant globules of spinning, cooling fragments.

The Earth became briefly flattened, its rotation driving its fluid form outwards.

Then the cloud expanded, suddenly, an eruption of light and fire, the energy embedded in its own substance being exploited to destroy it in a silent concussion.

Thus it ended, in a moment of unimaginable violence.

The debris formed a cloud, through which the plasma glow, fading, cast thousand-mile shadows.

Shallow gravitational waves crossed the Solar System, subtly perturbing the orbits of the planets.

Then, placidly, the remaining children of the sun resumed their antique paths, barely affected by the loss of their sibling.

Earth’s closest companion was more disturbed.

At the loss of the tides from its lost parent, the Moon shuddered. Water sloshed in its crater lakes, in giant circular ripples. Ancient faults gaped, for the first time in a billion years, and dusty lava flowed, as if the satellite was aping its parent’s demise.

Some humans died.

But it didn’t last long. And the inhabitants were prepared.

Then the orphan Moon sailed on, alone, cradling its precious cargo of humanity.

And, at the site of Earth, when the cloud of dust and volatiles and planetesimals dispersed, something new was revealed: a tear in space, a jewel of exotic particles, a wind of massless black holes fleeing at the speed of light.

Cautiously, tentatively, the ships from the Moon crept towards the ruin of Earth.

PART VI

NADEZHDA

…And, twenty years beyond the Bottleneck:

In the confines of Sagan’s airlock Nadezhda put on her gloves and snapped home the connecting rings. Then she lifted her helmet over her head.

The ritual of the suit assembly checklist was oddly comforting, a litany now decades old: in fact, almost unchanged from the routines endured by the original astronauts from Earth.

But the Sagan was no dinged-up low-Earth-orbit space truck, and right now Nadezhda was far from home.

She felt her heart hammer under her suit’s layers.

Jean Massie, on the hab module’s upper deck, was monitoring her. Nadezhda, you have a go for depress.

Nadezhda heard a distant hiss. “Let’s motor.”

She twisted the handle of the outer airlock hatch and pushed.

Nadezhda Pour-El Meacher Dundas gazed out into space.

She was looking along the length of the Sagan’s hab module. It was a tight cylinder, just ten yards long and seven wide, home to four crew for this six-month jaunt. The outer hull was crammed with equipment, the sensors and antennae clustered over powder-white and gold insulating blankets. The flags of the contributing lunar nations and agencies were here: NASA-L, the Russians, the Europeans, the Chinese, the Japanese, and the star-in-crescent flag of the Federal Republic of the Moon itself. At the back of the hab module she could see the bulging upper domes of the big cryogenic fuel tanks, and when she turned the other way there was the emergency return module, a capsule stuck sideways under the canopy of its big aerobrake.

The whole thing was just a collection of cylinders and boxes and canopies, thrown together as if at random. She knew every cubic inch of it.

She moved out through the airlock’s round hatchway.

There was a handrail, and two slide wires that ran the length of the curving hull, and Nadezhda tethered herself to the wires. It was a routine she’d practised a hundred times in the sims at Clavius and New Houston, and a dozen times in lunar orbit. There was no reason why now should be any different.

No reason, except that the Moon wasn’t where it should be.

In lunar orbit, the Moon had been a bright, curving carpet beneath her all the time. But out here, the Moon was all of five million miles away, reduced to a blue button three or four arms-lengths away. And Nadezhda was suspended in a huge three-hundred-sixty-degree planetarium just studded with stars, stars everywhere…

Everywhere, that is, except for one corner of the sky blocked by a vaguely elliptical shadow, sharp-edged, one rim picked out by the sun.

It was Icarus: a near-Moon asteroid, Nadezhda’s destination.

When she was selected for this mission, Nadezhda had studied the history of the Earthborn astronauts, right back to the beginning, Yuri Gagarin and Alan Shepard in their tin-can spaceships. She’d learned she had at least one thing in common with them.

She supported the objectives of the mission, of course. She had trained up on the science of Icarus, on near-Earth objects in general. She had trained up on the Moonseed, on the various coexistence and communications and exploitation schemes that had been proposed. She was interested in the science, the future of mankind, all of that stuff. Of course she was. She wouldn’t have come so far otherwise.

But what really motivated Nadezhda, here and now, five million miles from home, was not screwing up.

Every astronaut, right back to the beginning, had felt the same, she suspected. Don’t screw up. Finish the checklist, smile for the cameras. Because not screwing up was the only way to get on another flight.

Maybe that particularly applied to her, the first lunar-born deep-space astronaut, on this NASA-L mission. If she screwed up, the Earthborns would have a field day, and it would be a long time before she, or another Moonborn, would get another chance.

Of course, inevitably, their time would come.

All lunar citizens were astronauts anyway. The Earthborns just didn’t see that.

Under the big glass domes at Clavius and Tycho, human-powered flight was the most popular sport: thick air, low gravity…Nadezhda had grown up in a world where children flapped back and forth all the time like bony chickens, learning the rudiments of three-dimensional navigation and aerodynamics as soon as they were born.

And, on the Moon, everyone flew in space. You could reach orbit with a back yard rocket motor smaller than a car engine; even Armstrong and Aldrin had proved that. People went through sub-orbital lobs longer than Alan Shepard’s just to go shopping. Lunar inhabitants were nature’s astronauts.

But not to those Earthborn mission planners in New Houston, however.

She supposed it was pride.

Well, it would pass, with time. After all, when the present generation had retired, there would be no more Earthborn, ever.

So she put up with their prejudices, and waited for her own time to come, and listened to their stories — endless stories, five billion of them — tales of the time before the Bottleneck, of bravery and disaster and displacement — of unlikely acts of heroism linked with names in her own family lines — and of even earlier times, of an incomprehensible, vanished world, when everyone believed the Earth would forever be their home, as it always had…

But she didn’t want to wait for dead men’s shoes.