Daytime in the Driest Place

Polly slept until late morning. The residencia kept the windows blacked out for the night-shift astronomers, but a thin slot of brilliant white was visible at the curtain edge. The sun in the Atacama at noon was harder than anywhere Polly had been before.

Camila was still asleep. Most of the staff would not be up until five in the afternoon. The day-shift engineers and operations staff were on a different schedule from the astronomers. The cafeteria was running a quiet brunch. There was a man with a coffee at one table, in a green ESO polo shirt, reading a tablet.

His name, Polly learned, was Diego Castro. He was the senior site engineer at Paranal. He had been here for eleven years. He had grown up two hundred kilometres south, in Copiapó.

"Want to see the desert?" he asked Polly, without lifting his eyes from the tablet.

Polly tilted her head.

"I have a survey trip at two," he said. "Mostly inspecting a cable run. Forty minutes outside, then back. You can come."

That is how, at two in the afternoon, Polly found herself on the dashboard of a white Toyota Hilux driving deeper into the Atacama on a road that was, by some measures, not a road.

Diego drove slowly. He pointed out things as they went.

A dry riverbed where, three times in the last century, there had been a flash flood. The Atacama gets rain so rarely that when it does, it has nowhere to go. A 1962 storm killed people who had built houses in beds that had been dry for centuries.

A rock outcrop the colour of milk chocolate, full of small dark gravel. This was not gravel. This was meteorite-fall debris. The Atacama is one of the best places on Earth to find meteorites. The dry climate preserves them, and the bare ground makes them easy to see. Some meteorites found here have been sitting on the desert floor for over a million years.

A salar, a salt flat, blinding white against the rust hills. "Lithium," Diego said. "Most of the world's lithium is here, in salt flats just south of where we are. Your phone battery probably came from somewhere within a hundred kilometres of this view."

A small white sphere on a hilltop, perhaps a kilometre away. This was a microwave telescope, part of a different observatory. The Atacama has more than fifty separate observatories scattered across it. ALMA, the Atacama Large Millimeter Array, is further north, at five thousand metres of altitude. Paranal is one of many.

The air was so dry that Polly's beak felt different after twenty minutes. Diego made her drink water from a bottle, dribbling carefully. "You don't notice you're dehydrating here," he said. "You just stop being able to think straight. Then you fall over."

The cable run inspection took ten minutes. Diego walked the trench beside the road with a clipboard, checked four points, and pronounced everything fine. They turned around.

On the way back, the sun was already lowering. The shadows of small stones on the desert floor were long. Polly thought about how the Atacama, by some definitions, had been a desert for one hundred and fifty million years. The shadows here were the same kind of shadows that had moved across this floor when dinosaurs were still figuring out feathers. The patience of the place was hard to hold in her head.

They arrived back at the residencia at five. Camila was just waking up.