“But just think what you’d finish up with. A planet much more like Earth than Mars could ever be: continents called Aphrodite and Ishtar, oceans called Guinevere and Niobe; even enough geological activity to sustain a biosphere for billions of years.” He sighed. “It was always remote. But it was possible. Maybe that is why Venus was put in the Solar System in the first place.”

She eyed him. “As a place for us to colonize?”

“Why not? But now, it’s gone. Taken from us…”

“You sound as if you’re mourning. Mourning a planet.”

“A whole world has died here, Monica. Everything we could have learned from it, all its future possibilities lost, for all time. A world. What more appropriate object of mourning is there?… Maybe we ought to hold a wake. A global wake.”

She shivered, despite the warmth of the day. She was aware of Alfred watching her with barely concealed concern, but she had no time for that.

She looked around the bright sky for Venus, but it was either below the horizon or lost in the glare.

Henry Meacher flew British Airways direct into Edinburgh.

His ticket was for what BA called World Traveller Class, which meant, essentially, steerage. Henry found himself in a middle seat in the central bank of four, a long way away from the 747’s tiny windows. The stewardesses, expertly encased in make-up, were all anorexic-slim English girls with what he thought of as cut-glass accents; they walked as if their orifices were all sewn up. The distant communal video screen showed a BBC news round-up preceded by a tourist’s-eye view of the alleged ancient beauties of Britain; a little menu card told Henry he would be eating a roast beef dinner — American beef — and, later, a traditional English breakfast.

Henry buried his face in the Journal of Geophysical Research and tried to ignore all this fake Englishness. It was like a chintz spread thrown over the battered American engineering of the aircraft. Who did they think they were kidding?

BA irritated him. The Venus scare had caused a huge curtailment in long-haul flights, so every airline was suffering — the rules about every passenger wearing a radiation exposure dosimeter badge had seen to that — but even so the length of queues BA maintained at check-in astounded him. But they pretty much seemed to have a monopoly on direct flights to Britain aside from into London, so BA it was.

The flight was late leaving Houston Intercontinental. An O-ring on one of the ageing 747’s engines had to be replaced, and the engineers, worryingly, seemed to have trouble finding the right inspection hatch.

The seat next to Henry was occupied by a USAF airman who was stationed at a base in Suffolk. He was returning with his two kids from leave in Texas, and he was homesick before the Boeing left the ground. “The bathrooms in Britain are just disgusting. Even the hotels. They just never heard of sanitary seals. The Germans aren’t so bad with the bathrooms. But the French, my God, one place we stayed there was just a hole in the ground you were supposed to squat over…” Bathrooms on planes and on trains and in stations and in hotels, bathrooms in Britain and Italy and Greece and Sweden. It was, Henry realized with dismay, nothing so much as an asshole’s travelogue of Europe.

And after a couple of hours, the plane had metamorphosed, as ever, to a giant, stinking pig-pen in the sky, and every toilet Henry tried had a sticky floor and an overflowing trash can.

They flew out of bright morning light, from the west, towards Edinburgh. Henry peered out a window near the stewardess” station, and took his first look at Scotland.

He was descending into the Midland Valley, a broad belt of lowland that stretched from Glasgow to Edinburgh. This was actually what geologists called a graben: a rift, a block of land that had dropped between two faults. He could see the roads from England, to the south, sweeping down out of the hills to the valley floor, which was settled and arable, coated with picture-book fields and towns, though he could see, in some places, the scars left by Venus: failing crops, fields left brown and bare, a portent of troubled times to come.

But what made this valley different were the extinct cores of old volcanoes that stuck out of the ground, remnants of a volcanism spasm three hundred million years gone. The cones were an uncompromising demonstration of the old geologist’s saw that the stuff that’s left sticking out of the ground is harder than whatever has been worn away.

And as he descended towards Edinburgh itself he caught a glimpse of Arthur’s Seat, a composite volcano that was the greatest of the volcanic plugs; the buildings of the old city lapped around its flanks.

He landed at 7.00 a.m. local, having missed an entire night out of his life. A bright early spring day stretched ahead of him, and he felt like a piece of shit.

“The name’s Mike Dundas.”

The kid was waiting for Henry at the departure gate, when he finally got through queuing to have his passport checked.

Henry shook his hand. “We e-mailed. Good to meet you, Mike.”

Mike took Henry’s bag, a wheeled suitcase, and hauled it away through the terminal towards the car park. Mike was a technician in the University geology department here; he was in his early twenties, with — to Henry’s eye — brutally short-cut hair, a disconcertingly pierced nose, placid blue eyes. He wore the bright Day-Glo sunscreen popular with the young around the world, huge dabs of orange and yellow on his nose and cheeks. His accent was distinctly Scottish, but gentler than Henry had expected — lots of strong r’s, “ye” for “you’, “tae” for “to’, and so on. No big deal.

“The rock’s already here,” Mike said.

“The rock?”

“86047. The Moon rock. We’ve set up our sample lab. I don’t mind telling you we’re all excited about this, having the rock here.”

“It’ll be glad to know it’s a celebrity.”

Mike looked cut by the mild sarcasm, and Henry instantly regretted it.

“I’m sorry,” Mike said. “We’re glad to welcome you too, sir.”

“I know what you meant, Mike. And for Christ’s sake call me Henry; you make me feel old enough as it is.”

“I’m sorry.”

“Stop apologizing, already.”

“I’m—” Mike laughed, and seemed to relax a little. “You’re the boss.”

Mike’s car, in the multi-level airport car park, turned out to be a small, battered Rover. Henry, unfamiliar with the Brit numberplate system, couldn’t tell its age, but he was willing to bet it hadn’t been radiation-proofed according to the new international code. There was room in the trunk — no, the boot — for Henry’s luggage, but Mike had to clear boxes and papers off the seats before Henry could sit down.

“Sorry,” Mike said. “I wanted to pick you up myself. But the car’s always full of shit.”

Henry shrugged as he buckled up his seat belt. “We’re geologists, remember. Geologists live in shit. It’s in the job description.”

“Here.” Mike handed Henry a cardboard carton of orange juice.

“What’s this for?”

“Jet lag. I know how it feels.”

Henry grinned, and held the carton to his mouth.

Mike queued his way out of the car park, and set off along the freeway — motorway — towards central Edinburgh, eight miles away. The sky was blue, fresh, marked by a few moist-looking cumuli; but, when Mike opened a window, it was cold.

He became aware that Mike hadn’t spoken since the airport. Mike seemed to have picked up Henry’s inner sourness; maybe the poor kid thought Henry’s mood was somehow his fault.

“So,” Henry said with an effort. “What’s the shit, specifically? The boxes in the car.”

“Oh.” Mike looked vaguely embarrassed. “They’re for my sister. I get her samples through my buddies at the University. She sells rocks.”