“Right. And your nuke is going to melt it all.”

“Oh, no.” He sounded surprised. “Don’t you get it? To melt all that ice would take the energy of…” He thought about it. “Maybe ten times Earth’s whole nuclear arsenal.”

“So how is the bunker-buster going to work?”

She could hear the grin in his voice. “Judo.”

Suddenly, she felt weary. She just wanted done with all of this, all these schemes and plans, one way or the other.

She closed her eyes.

“You’ve got to be a believer,” he whispered gently.

Arkady checked the controls set out before him. There were instruments and switches for the main systems, a TV screen, and an optical orientation view-finder set up on a small porthole next to the panel; there were orientation controls on his right, and manoeuvring controls to his left. His small laptop, with its weapons controls, was fixed to the couch to his right.

For the nuclear device, he had rigged a simple dead man’s switch. If possible, he would set the timer after a careful emplacement. But if power was lost, the device would detonate anyway.

His craft was prepared, and the weapons it carried.

He closed his hands around the joysticks that controlled the spacecraft’s systems. There was no computer program to control what he was going to attempt, with this poor Soyuz; he must lead it perhaps to its destruction himself.

He was ready.

Two minutes left. Just ten thousand feet now. The Moon ground fled beneath him, flattening, bellying up towards him.

His descent was actually very shallow — just ninety feet in every mile, much shallower than even a civilian airliner. His path, in fact, was almost tangential to the Moon’s surface. But his speed was gigantic. The pocked ground fled beneath him, like a scarred runway in the last few feet of a descent.

One minute.

Five thousand feet up, and he was still sixty miles from his goal.

The land seemed to flatten further, the close horizon receding.

And then he flew past the flank of a round-shouldered lunar mountain, grey, pock-marked. Its shadowed far side was limned by a graceful, powdery curve of sunlit regolith, and its summit was lost above him.

As soon as he perceived the mountain, it was gone, lost behind him, as unreachable as his childhood.

Twenty seconds. Less than two thousand feet. The craters ahead were foreshortened to ellipses, pools of shadow in the sunlight, flattening.

He flew into shadow, and he could see no more.

And so, in darkness, Arkady — still moving at a mile a second, sitting up in his couch — hit the surface of the Moon.

Arkady’s life, the success of his mission, was utterly dependent on Henry’s theories.

At the moment of touchdown — the instant at which the rounded belly of the Soyuz impacted the lunar dirt — two things happened.

First, the attitude thrusters beneath Arkady’s feet fired on full strength, lifting Soyuz away from the regolith. The thrust was sufficient to hold eighty per cent of the Soyuz’s weight up from the surface; the actual depth of contact ought to be no more than a few inches. Other thrusters fired intermittently, to keep the craft upright, stop it tumbling.

Second, the Star Wars laser fired from the craft’s nose.

If this South Pole crater was indeed a frozen lake of water, dusted over by regolith, then the laser should blast-melt a shallow furrow, a canal of glowing steam, utterly straight ahead of Arkady. The liquid water — persisting for a few seconds before boiling away — would lubricate the ferocious contact between the hull of the Soyuz and the ancient ice.

The Soyuz would shed its orbital speed in friction with the water, and — sliding home like a baseball player coming to a plate — would come to a gentle halt, with barely any fuel expended.

That, at any rate, was the theory.

A hundred seconds and it would be over, one way or another.

Arkady was thrust forward against his chest restraints. The impact was violent, spine-jarring, harder than he expected.

The Soyuz groaned like a tin can. The craft rattled and jumped, as if some giant were battering its hull, the vibration so violent he could no longer see the instruments. The deceleration should be less than one and a half G, but it was a long time since he had been on Earth, and it was in any case the vibration that was shaking him to pieces.

…But the craft held. The cabin lights flickered, but stayed bright.

The pressure, the noise and vibration, continued. He struggled to stay upright, to keep breathing. His ribs ached, and there was a greying around the rim of his vision.

He heard a series of jolts and bangs: that was the solar panel wings, the optical sighting system periscope, perhaps the rendezvous antenna on its stand, being ripped off the hull. His craft was being stripped down to its basics by this brutal passage.

In the first ten seconds, hardly any of his velocity gone, he covered ten miles, scouring across the Moon’s shadowed surface.

But the seconds wore on, his heart continued to beat, and the structure of the craft was still holding. He allowed himself a grin. This rattling Soyuz was a tank, ploughing resolutely through the lunar ice; the Americans” tin-foil Apollo would not have lasted a dozen yards!

He caught glimpses of the Moon, fleeing past his window: dune fields lit up by a red, spectral glow, obscured by sprays of steam. The glow was his own, he realized: it was the hull of his Soyuz and the dirt of the Moon, turned red hot by his spectacular arrival.

He must be a wonderful sight, raising parabolic plumes of glowing spray and steam to either side, as he cut his geometrically straight line across the surface of the Moon. If the Moon were tipped up a little more, in fact, on Earth they would even be able to see, with the naked eye, the gash he must cut in the surface.

Twenty seconds, seventeen miles covered; thirty seconds, twenty-four miles…

His velocity was dropping, then, almost as planned. Yet the ride grew no less violent, the shuddering dips and bangs of the craft no less pronounced. Sometimes the bangs were very severe, as the Soyuz hit some inhomogeneity in the ice.

Suddenly the deceleration increased, and he was thrown with fresh vigour against the restraint straps. But he had been expecting that; as his velocity reduced the Soyuz was sinking more deeply into the lunar ice, digging in, braking him more rapidly.

Now a full minute had elapsed since that first jarring touchdown, and, by God, he was still breathing. Just ten miles to go, and his speed must be no more than Mach Two, and falling…

He had of course broken all land-speed records in the process of this landing. And, whatever the outcome, he would become the first human to die on another planet, the first to create a myth on this world without history, without monuments. Let them engrave that on the statue they would build to him, on Leninski Prospect!

Seventy seconds, eighty; forty-five miles, forty-seven. The shuddering of the craft, the howling of the metal scraping on poorly-lubricated ice, all of it seemed to him to be smoothing out and reducing. The vibration now was much diminished, and he was even able to read his instruments.

Ninety seconds. Another lurch, a plummet downwards, another savage bite of deceleration.

Now the attitude thrusters had cut out, and he would complete his final glide unpowered, the Soyuz ploughing ever deeper into the ice of the Moon.

Ten more seconds. The Soyuz slowed in violent lurches, and Arkady was still pinned forward against his straps. But he felt exultant. It had worked, by God! His speed was now no more than a couple of hundred miles per hour, and he began to believe, cautiously, that he might actually live through this. He would be a Russian cosmonaut, alive on the Moon, even if for just a few minutes or hours… It would be glorious!