Prologue

On the outskirts of our solar system there is a ring of broken lumps of rock and ice. They form a roughly spherical border marking the outer reaches of the sun’s influence, a loosely strung fence around our stellar home. Against this backdrop, a meteor the size of Central Park flies past.

Not that its size is particularly unusual.

Size, like speed and distance, can only be judged as usual or unusual when taken in context. So as we consider this particular meteor, even though it is the size of Central Park, or about three times the size of the largest aircraft carrier on earth, it is dwarfed by the multitude of extra-stellar debris relegated by chance to the cold, distant reaches of our sun’s gravitational well, which, in turn, are made minuscule, negligible even, by the unfathomable expanse of the void beyond.

All that said, no human eye could compare them in order to judge the disparity. For even if someone happened to be in the vicinity as this particular meteor came by, its passing would be so fantastically fast as to be imperceptible, and would do little to break what would be a phenomenally boring existence for this lone stellar observer. For this is a place that any vessel we could build would take more than a lifetime to reach, and it would probably be even less interesting up close than it has been in the glimpses we have snatched by telescope. No, to travel from this point to the earth in the two months it will take this meteor to get there, you would have to be going at the blurringly astonishing rate of two thousand kilometers every second, at which speed you could circumnavigate the Earth twice in less than a minute.

Of course, this meteor’s seemingly incredible speed is also not that exceptional, for an interstellar body, which, though rare, are not unheard of.

No, the only truly exceptional thing about this meteor is that spread out behind it by a complex, invisible web of magnetic forces is a vast, atom-thin surface, so thin that matter passes through it unhindered, leaving it unharmed by the cosmic dust that would otherwise tear anything so huge to shreds. Its delicate mesh reflects only a small wavelength of plasma. Catching and resisting this particular wavelength, however, in this ocean-sized parachute, means that the very sun the meteor is rushing toward is filling the thousand-mile-wide radiation chute with solar wind.

Indeed the only exceptional thing about this meteor is not its size, which is puny compared to its neighbors, or its spectacular speed, which, though rare, is far from unique. No, what would have astonished any spectator that could see this particular meteor is that this particular meteor is slowing down.

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