The shuttle’s orbital trajectory gave them only a limited amount of time near the mirror, prompting the astronaut to act quickly. In an almost unconscious act the moment the fog disappeared, he took a wrench out of his tool bag and tossed it at the mirror, but once it left his hand, he and the astronauts aboard the shuttle were paralyzed with the realization that the relative velocity between it and the mirror gave it the force of a bomb. In terror they watched the wrench tumble toward the mirror and had a vision of the spiderweb fractures that in just moments would spread like lightning across the surface from the point of impact, and then the enormous mirror shattering into billions of glittering fragments, a sea of silver in the blackness of space…. But when the wrench touched the surface it vanished without a trace, and the mirror remained as smooth as before.
It actually wasn’t hard to see that the mirror was massless, not a physical body, since floating motionless over Earth’s North Pole would be impossible otherwise. (It might be more accurate to state, given their relative sizes, that the Earth was floating in the middle of the mirror.) Rather than a physical entity, the mirror was a field of some sort. Contact with the fog and the wrench proved that.
Delicately manipulating his thrusters and making continual microadjustments of the jets, the astronaut drew within half a meter of the mirror. He stared straight into his reflection, amazed once again at its fidelity: a perfect copy, one perhaps even more finely wrought than the original. He extended a hand toward it until he and his reflected hand were practically touching, separated by less than a centimeter. His earpiece was silent—the commander did not order him to stop—so he pushed forward, and his hand disappeared into the mirror. He and his image were joined at the wrist. There had been no sensation of contact. He retracted his hand and looked at it carefully. The suit glove was perfectly unharmed. No marks whatsoever.
Below the astronaut, the shuttle was gradually drawing away from the mirror and had to constantly run its engines and thrusters to maintain proximity. However, due to its trajectory its drift was accelerating, and before long such adjustments would be impossible. A second encounter would require waiting an entire orbit, but would the mirror still be there? With this in mind, the astronaut made a decision. He switched on his thrusters and headed straight into the mirror.
His reflection loomed large, filling his field of vision with the quicksilver bubble of his helmet’s one-way reflective faceplate. He fought to keep from closing his eyes as his head touched the mirror. At contact he felt nothing, but in that very moment everything vanished before his eyes, replaced by the darkness of space and the familiar Milky Way. He jerked around, and below him was the same view of the galaxy, with one addition: his own reflection receding into the distance, the maneuvering units he and his reflection wore linked by streams of thruster jet fog.
He had crossed the mirror, and the other side of it was a mirror, too.
His earpiece had been chirping with the commander’s voice when he was approaching the mirror, but it had cut out. The mirror blocked radio waves. Worse, the Earth wasn’t visible from this side. Surrounded entirely by stars gave the astronaut the feeling of being isolated in a different world, and he began to panic. He adjusted the jets and arrested his outward motion. He had passed through the first time with his body parallel to the mirror, but now he oriented himself perpendicular, as if diving headfirst into it. Just before contact, he cut his speed. Then the top of his head touched the top of his reflection, and then he passed through and saw with relief the blue Earth below him, and heard the commander’s voice in his ear.
Once his upper torso was through he dropped his drift speed, leaving the remainder of his body on the other side. Then he reversed the direction of his jets and began to back up; fog from the jets on the opposite side of the mirror issued from the surface around him like steam rising from a lake in which he was partially submerged. When the surface reached his nose, he made another startling discovery: The mirror passed through his faceplate and filled the crescent space between it and his face. He looked downward and saw his frightened pupils reflected in the crescent. No doubt the mirror was passing through his entire head, but he felt nothing. He reduced his speed to the absolute minimum, no faster than the tick of a second hand, and advanced millimeter by millimeter until the mirror bisected his pupils and vanished.
Everything was back to normaclass="underline" Earth’s blue sphere on one side, the glittering Milky Way on the other. But that familiar world persisted only for a second or two. He couldn’t reduce his speed to zero, so before long the mirror was above his eyes, and the Earth vanished, leaving only the Milky Way. Above him, the mirror blocking his view of Earth extending hundreds of thousands of kilometers into the distance. The angle of reflection distorted his view of the stars into a silver halo on the mirror’s surface. He reversed thrusters and drifted back, and the mirror dropped down across his eyes, vanishing momentarily as it passed to reveal both Earth and Milky Way before the galaxy vanished and the halo turned blue on the mirror’s surface. He moved slowly back and forth several times, and as his pupils oscillated on either side, he felt like he was passing across a membrane between two worlds. At last he managed a fairly lengthy pause with the mirror invisible at the center of his pupils. He opened his eyes wide for a glimpse of a line at its position, but he saw nothing.
“The thing’s got no width!” he exclaimed.
“Maybe it’s only a few atoms thick, so you just can’t see it. Maybe it approached Earth edgewise and that’s why it arrived undetected.” That was the assessment of the shuttle crew, who were watching the images sent back.
The astonishing thing was that the mirror, perhaps just atoms thick but over a hundred Pacific Oceans in area, was so flat as to be invisible from a parallel vantage point; in classical geometry, it was an ideal plane.
Its absolute flatness explained its absolute smoothness. It was an ideal mirror.
A sense of isolation replaced the astronauts’ shock and fear. The mirror made the universe strange and rendered them a group of newborn babes abandoned in a new, unfathomable world.
Then the mirror spoke.
THE MUSICIAN
“I am a musician,” it said. “I am a musician.”
The pleasing voice resounding through space was audible to all. In an instant, all sleepers on Earth awoke, and all those already awake froze like statues.
The mirror continued, “Below I see a concert whose audience members are capable of representing the planet’s civilization. Do you wish to speak with me?”
The national leaders looked to the secretary general, who was momentarily at a loss for words.
“I have something to say,” the mirror said.
“Can you hear us?” the secretary general ventured.
The mirror answered immediately, “Of course I can. I could distinguish the voice of every bacterium on the world below me, if I wanted to. I perceive things differently from you. I can observe the rotation of every atom simultaneously. My perception encompasses temporal dimensions: I can witness the entire history of a thing all at once. You only see cross sections, but I see all.”
“How are we hearing your voice?” the US president asked.
“I am emitting superstring waves into your atmosphere.”
“Superstring waves?”
“A strong interactive force released from an atomic nucleus. It excites your atmosphere like a giant hand beating a drum. That’s how you hear me.”