The ambassador’s confusion turned to contemplation. The six suns were heading west and soon dipped below the horizon. When only two remained, Venus rose, and then rays of the true sun’s dawn spread from the east. Its gentle light gave the ambassador a smidgen of comfort; some things, at least, were unchanging in the universe.

“Five hundred years isn’t all that long. Why have things changed so much?” she asked, as much to the whole world as to the captain.

“The acceleration of human progress. Compare our fifty years of progress to the previous five centuries. It’s been another five centuries, which might as well be fifty millennia. Do you still think migrants can adapt?”

“And what’s the end point of this acceleration?” the ambassador asked, eyes narrowed.

“I don’t know.”

“There’s no answer to that question in the sum total of human knowledge you possess?”

“The strongest feeling I’ve gotten from my time in this age is that we’re beyond the time when knowledge can explain everything.”

“We’ll continue onward!” the ambassador decided. “Take that chip with you, as well as their device for importing knowledge into the brain.”

The ambassador saw Hua again before entering the haze of supersleep, only a glance after 620 years, a captivating, heartbreaking glance, but it anchored her to home within the lonely flow of time. She dreamed of a cloud of dust drifting over the crystal ground—was this the form his bones now took?

THE TREK

Outside of perception, the sun swept through the sky like a shooting star, and time slipped past in the outside world.

… 620 years … 650 years … 700 years … 750 years … 800 years … 850 years … 900 years … 950 years … 1,000 years.

STOP 3: THE INVISIBLE AGE

The sealed door to the freezer rumbled open and for a third time the ambassador approached the threshold of an unknown age. This time she had mentally prepared herself for a brand-new era, but she discovered that the changes weren’t as great as she had imagined.

The crystal carpet that blanketed the ground was still present and six suns still shone in the sky. But the impression given by this world was entirely different from the Lobby Age. First of all, the crystal carpet seemed dead; although there was still light in the depths, it was far dimmer, and footsteps no longer tinkled on its surface, nor did gorgeous patterns appear. Four of the six suns had gone dim, the dull red they emitted serving only to mark their position but doing nothing to light the world below. The most conspicuous change was the dust. A thin layer covered all the crystal. The sky wasn’t spotless, but held gray clouds, and the horizon was no longer a ruled line. It all contributed to a feeling that the previous age’s lobby had gone vacant, and the natural world outside had begun to invade.

“Both worlds refuse to take migrants,” the advance-team captain said.

“Both worlds?”