PICTORIAL: THE ROCKET BUS ARRIVES AT TMA-1 EXCAVATION

TMA-1 EXCAVATION: Floyd, Halvorsen, Michaels, a photographer, and two others approach the ramp entrance of the excavation. It's illuminated with a bank of lights.

All of them stand motionless and in silent appreciation.

The monolith is completely inert. No sound or energy sources have been detected. At first glance, black would suggest something sun-powered, but then why would anyone deliberately bury a sun-powered device? And so this is the first sun that it's had in four million years.

The surface is made of something incredibly hard and Halvorsen's team have been barely able to scratch it. They considered trying a laser drill, but they didn't want to be too rough until they knew a little more. They were able to determine it was deliberately buried by the deformation between the mother rock and the fill.

Was it abandoned, forgotten, left for a purpose? Was it a tomb, a shrine, a survey-marker, a spare part? No one knew, the only thing about it that they were sure of, is that it is the first direct evidence of intelligent life beyond the Earth. Four million years ago, something, presumably from the stars, must have swept through the solar system and left this behind. The moon would have made an excellent base camp for preliminary Earth surveys.

The photographer motions the others to line up in front of the monolith to take a few photographs. Floyd stands in the middle with Michaels and Halvorsen on each side.

The photographer motions his hand for them to stand closer to each other.

As the men form their picture pose, suddenly there is a piercingly powerful electronic shriek, like a hideously over-loaded and distorted time signal.

Floyd involuntarily tries to block his ears with his hands. Then comes merciful silence.

A hundred million miles beyond Mars, in the cold loneliness where no man had yet travelled, Deep-Space-Monitor-79 drifts slowly among the tangled orbits of the asteroids. Radiation detectors noted and analyzed incoming cosmic rays from the galaxy and points beyond; neutron and x-ray telescopes kept watch on strange stars that no human eye would ever see; magnetometers observed the gusts and hurricanes of the solar winds, as the sun breathed million mile-an-hour blasts of plasma into the faces of its circling children.

All these things and many others were patiently noted by Deep-Space-Monitor-79, and recorded in its crystalline memory. But now it had noted something strange - the faint yet unmistakable disturbance rippling across the solar system, and quite unlike any natural phenomena it had ever observed in the past.

It was also observed by Orbiter M-15, circling Mars twice a day; and High Inclination Probe-21, climbing slowly above the planet of the ecliptic; and even artificial Comet-5, heading out into the cold wastes beyond Pluto, along an orbit whose far point it would not reach for a thousand years. All noticed the peculiar burst of energy that leaped from the face of the Moon and moved across the solar system, throwing off a spray of radiation like the wake of a racing speedboat.