“The spacecraft cemetery is where they’re dropped. It’s the center of the South Pacific, about as far from land as you can get on this planet, somewhere between Easter Island and Antarctica. There’s been around three hundred spacecraft sunk there over the years. The Mir space station’s down there, various resupply craft belonging to the ISS, some transfer vehicles from the European Space Agency. It’s a junkyard over thousands of square kilometers, as deep under the sea as you can go.

“Obviously, none of them is just sitting neatly on the ocean floor. Re-entering the atmosphere is like being hit by a bomb. The heat generated can burn metal. But that’s not to say you don’t get some interesting fragments. And piloted vehicles like the Space Shuttle or Russia’s Soyuz capsules have thermal shielding to protect them. The Chinese wanted to know what they could find, but also what of theirs the Americans might be able to find. I was instructed to help prepare an assessment, show them how it could work. I told them it was near impossible—looking for a satellite the size of a car in the Pacific, trying to retrieve a sea drop. You needed razor-sharp trajectory prediction followed by ultrafast response using vehicles that could go deep.

“I don’t know if you know how deep the ocean goes. The Spacecraft Cemetery is down in the abyssal zone. That’s about four to six thousand meters below the surface. There’s no life down there. Maybe sponges, the odd octopus or viperfish. The water pressure means diving’s impossible. But if anyone could do this work, it was me. The underwater vehicle I use has speed and, more importantly, thermographic cameras. For recent drops you’re not looking for something cold but something hot. And the Chinese were improving their location estimates. A couple of days before a spacecraft drops, whichever space agency is in charge of it has to notify authorities in Chile and New Zealand. Those countries share responsibility for the cemetery, and they publicize expected re-entry times and where debris is likely to fall. The Chinese had access to all that. They also had extensive systems of submerged microphones each with a range of several hundred miles. And for a while, of course, you have heat, a lot of heat. But satellites sink fast.”

As Lau described it, they’d set off—sometimes from Easter Island, sometimes from Concepión in Chile—sail three or four days, anchor at designated coordinates until instructions came in. At that point you were already above the abyss; nothing but water beneath you for thousands of feet.

“Then, as soon as we had word of impact, we’d begin searching.”

At three thousand feet you were entering what he called the midnight zone, light fading, six thousand pounds of pressure per square inch.