The sense of motion surprised him. No feeling of acceleration, of course; but still the Earth unrolled beneath him, new features washing steadily over the horizon, littered with clouds that were strikingly three-dimensional. Here came the Florida peninsula, for instance, like a raft of land suspended on the royal blue waters of the ocean, its coast fringed by a delicious electric blue, the shallower ocean floor of the continental shelf. A little way out to sea, over the Atlantic, a bank of cloud was gathered in great three-dimensional ripples, like scoops of ice cream layered over the pond-like air. On the land itself, he could make out the spit of land that marked Cape Canaveral. Straight inland from that, surrounded by the central lakes, he could see the Disney World complex, splashes of white and grey. On the other side of the peninsula he made out Tampa Bay, and Miami in the south. The cities were bubbly grey, their boundaries blurred. The whole thing looked like a map — but in three dimensions, with that visibly thick layer of air above it.

He was struck by the land’s flatness, the way it barely seemed to protrude above the ocean’s skin. In fact Florida was indeed a karst topography, a bed of limestone laid down in a shallow, ancient sea, and the lakes were just hollowed-out sinkholes in the limestone. Little separation between land and sea.

But his view was never stable. The spacecraft turned, slowly, so that its big, wing-like solar panels caught the sunlight. If Henry craned his head he could see the panels, jutting out like an airplane’s wings from the hull of the ship, the solar cells gleaming gold, as the Soyuz turned like a flower to the light.

They flew into darkness: what Geena called the shadow, the dark half of the orbit. Reflections from the cabin lights on the windows made it hard to see out at such moments, but still Henry could make out continents outlined by cities, chains of them like streetlights along the coasts, and penetrating the interiors along the great river valleys. The strings of human-made light, the orange and yellow-white spider-web challenging the night, were oddly inspiring.

Over the Pacific’s wrinkled hide he saw a dim glow: it was the light of the Moon.

And then they flew towards the sunlight once more. It was quite sudden: a blue arc, perfectly spherical, suddenly outlined the hidden Earth, and then the first sliver of sun poked above the horizon. The shadows of clouds fled across the ocean towards him, and then the clouds turned to the colour of molten copper. The lightening ocean was grey as steel, burnished and textured. The horizon brightened, through orange to white, and the colours of life leaked back into the world.

He had the feeling he could spend his life up here and not tire of this.