Or in a few centuries.

“Pan view.”

The computer heard her words and adjusted the image. The planet shrank to pea size, a bright bead of light at the middle of the screen. The surrounding nimbus of intensive in-space construction was revealed, a gleaming nacreous setting within which the planet nestled like a pearl in an oyster. Slender tendrils of construction stretched out endlessly, thinner and thinner, until they fell below the resolution of the observing sensors.

“Not our kind, Tamara,” the man said softly. “That’s not us.”

No human works, not even the ring cities that surrounded Earth itself, came close in size and complexity. Some of the spiraling filaments around the planet had to be over four hundred thousand kilometers long and many kilometers across. They should have been unstable to gravitational forces from the planet, to tidal perturbations, and to their own interactions. And yet clearly they were not.

“Time to wake the others,” Tamara said.

“And then?”

“And then…” She sighed. “And then, I don’t know what. We finally did it, Damon. We found another intelligent species. A technologically advanced one, too. But if they could build that” — she gestured at the dazzling structure on the screen, and her voice became husky — “why didn’t they find us? Well, I guess we’ll know the answer to that in a few more days.”

Three weeks later the ship’s pinnaces were roving the veins and arteries of the space artifact. For fifteen days the main vessel had hovered five million kilometers away, waiting for and expecting contact from the planet in response to radio and laser signals. They had been met with total silence. Finally they had approached and begun direct exploration.

The misty filaments on the screen resolved themselves to the interlocking network of a colossal artifact. They stretched down to the surface of the planet, an uninhabited world apparently well suited to human colonization; but the tendrils also reached far out into space, for purposes that could not even be guessed at.