Prologue

It came at unimaginable speed.

From beyond the solar system, it came. Large as a planet and faster than a comet, the object barreled in from interstellar space. The object is a nomad, a rogue planet, with no solar system to call home. It is destined to spend eons floating through empty space, rarely privileged to enter solar systems such as this.

The object is neither the first nor the last of its kind to visit this solar system. In fact, 300,000 years into the future, a smaller visitor will arrive just in time for a civilization in this system to recognize it, who will dub it ‘Oumuamua. However, the arrival of the object has ensured that this civilization will never come to exist.

The object sped toward the Sun, its trajectory slicing into the ecliptic at a fine angle. It made its closest approach to the Sun, the closest it has gotten to a star in billions of years, and followed its hyperbolic orbit that will take it back to the black abyss. It will have to wait billions of years more to experience the warmth of a star again. It would, that is, if it weren’t for the orbit of another, more massive object.

This larger object is Earth, one of the Sun’s planets, and the abode of life in this solar system. As fate may have it, as the object flew away from the Sun, it barreled toward Earth. The object approached the planet as the planet approached the object, both following their orbits. The distance between them shrank and shrank, until the object’s path began to bend in Earth’s gravity, as the more massive Earth accelerated. Their separation became so small that a collision seemed inevitable, ready to wipe this planet clean of all but the simplest life.

Fortunately, their trajectories were just short of mutual destruction. Instead, the object made a close approach to the planet and shot off in a different direction. Robbed of much of its kinetic energy, this object can no longer escape into interstellar space. It will finally find a home in the Oort cloud.

Though it narrowly missed extermination, Earth will never again be the same. The extrasolar object had given Earth a gravity assist, giving it a higher velocity and pushing it into a larger orbit around the Sun. With both the object and the Sun fading in the eyes of Earth’s many and varied inhabitants, the world will experience a change like no other.