Bud said at last, You know, at times like this I still miss a cigarette.
At heart youre just an unreconstructed high school jock, arent you?
Salt of the earth. He stared at the ceiling. But this trip is business, not pleasure, isnt it?
Im sorry.
He shrugged. Dont be. But lookas far as everybody else is concerned, youre here for the AI switch-on. Nobody but my PA knows about the other stuff.
Faintly irritated she said, Im not here to hurt morale, Bud. Im supposed to be strengthening the project, not weakening it. Thats the whole point. But
But this business of the audit has to be cleared up. He held her hand. I know. And I trust you to handle it well.
She churned with guilt. Bud, we both have our duty. And we cant let anything get in the way of that.
I understand. But a bit more pleasure before business. He sat up. Weve got twelve hours before we boot up the AI. Lets go do some sightseeing.
They washed, dressed, and drank a coffee. Then Bud escorted her to the little ship he called the V-Eye-P.
The projects one and only one pressurized inspection module was just a platform laden with spherical fuel and oxidizer tanks and a small set of hydrazine rocket motorsactually attitude thrusters cannibalized from a retired spaceplane. On top was a pressurized tent of Kevlar and aluminum, within which two people could stand side by side. That was it, save for a simple set of controls based on a joystick that sprouted from the floor, and a life support system that would keep you alive for six hours at a pinch.
The shield engineers used variants on this design, but just the platform and the engines, without the tent: why bother with a pressure cabin when you had a perfectly good spacesuit? So you would see engineers skimming over the surface of the shield riding their rocket-propelled boxes like scooters. Only this one special little craft was kept aside for VIPs, visitors like Siobhan who didnt have the time or inclination to get trained up on how to use a pressure suit.
Not, Bud said with a faintly malicious grin, that this Kevlar tent would be much protection if anything went wrong
The V-Eye-P was launched from Auroraby an electromagnetic induction rail, like a miniature version of the Sling, the giant mass driver on the Moon. The acceleration was smooth, like a rapid elevator; Siobhan quite enjoyed the feeling of her feet being pressed to the floor.
When they had climbed sufficiently far, Bud tested the little ships rockets, burping them as he called it. It sounded as if small explosions were going off all around the Kevlar hull. Bud explained that there was no exhaust from the induction rail, and rockets, however small, were never used close to the shield. Were building a mirror made of frost laced on spiderweb, he said. We try not even to breathe on it.
The craft swiveled and pitched to and fro. It was like being aboard a rather odd fairground ride.
When he was satisfied, Bud brought the craft to a halt and tipped it forward so Siobhan could see down. Behold the mother ship, he said.
The venerable old Aurora2 was still the centerpiece of the shield, still the spider at the center of the web. Despite extensive cannibalization, Siobhan could make out the main features she remembered: the long, elegant spine with the fat habitation module at one end, and the complex clusters of power plants, fuel tanks, and rocket engines at the other. Shes a game old bird, Bud said fondly. I hope she forgives us. She still has a role to play, keeping the shield spun up and oriented correctly. Of course all that will change when the AI comes online and the shield starts to control itself.
He pulled back on his control stick, and the platforms thrusters banged. The little ship rose up smoothly, rising away from the shield along an axial line that led straight up from the embedded Aurora.
Siobhan stared out, fascinated, as the shield opened up beneath her. Away from the old Mars ship the shield was a floor so flat and smooth it was like a mathematical abstraction, a semi-infinite plane that cut the universe in half. The surface shimmered, as delicate as a soap bubble, and as she rose higher prismatic rainbows fled across the surface. But the shield was still edge-on to the sun, and the low light streamed through that delicate membrane, so that she could make out the spindly skeleton beneath, struts, spars, and ribs of delicate lunar glass, a fairyland scaffolding that cast long, slim shadows.
Its wonderful, she said. The most massive engineering project anybody ever undertook, and yet it is nothing but glass and light. Like something from a dream.
Which is why, Bud said a bit mysteriously, Ive chosen the name I have for herthe shields AI, I mean.
Her? But he would say no more.
He pulsed the attitude control thrusters again and tipped the platform backward, so its windows swiveled to face the Earth. The home planet was a perfect blue marble hanging in space. The Moon, white-brown, sailed beside its parent, some thirty Earth diameters away. L1 was far beyond the orbit of the Moon; from here, there was no doubt this was a twin world.
Home, Bud said simply. Stuck out here its good to be reminded of what were working our butts off for. He leaned close to her, and pointed so she could sight along his arm. See there? And there?
Against the velvety darkness of space she saw sparks drifting, two, three, four of them in a rough line, like fireflies in the night, passing from Earth to shield.
Bud tapped the window. Magnification please.
The image in the window before Siobhan exploded in rapid jumps. Now she could see perhaps a dozen ships. Some were just large enough to show detail, hull markings, solar-cell arrays, antenna booms. The convoy looked like toys, models suspended against velvet.
A caravan from Earth, bringing up the smartskin. Bud was grinning. Crawling its way up the gravity hill to L1. Isnt that a fantastic sight? And its been going on, day and night, for years. If you turn a scope on the dark side of Earth, you can see the sparks of all those launches, over and over.
On the ground, Siobhan had inspected the collection processes. Smartskin blankets, grown out of household windows like Bisesa Dutts in London, were gathered at neighborhood collation points, and then shipped to big storage centers at the airports and spaceports, and finally bundled up and sent to one of the great launch centers at Cape Canaveral, Baikonur, Kourou, or Woomera. Just the ground operation was a stupendous enterprise, a mighty international flow across the face of the Earth. And it culminated in these sparks bravely crossing the night.
Bud said, You know the picture. Were throwing everything weve got into the launches, just like every other aspect of the project. They even dug the space shuttles out of their museums at the Smithsonian and Huntsville, and got those beautiful birds flying again. Worn-out shuttle main engines, too beat-up to be human-rated anymore, are being recycled: you can make a pretty useful throwaway booster out of a shuttle tailplane and a cargo pallet. The Russians have brushed off their old plans for Energia and have got those big old rockets flying again too.
But even that isnt enough. So Boeing and McDonnell and the other big contractors are churning out boosters like sausages. Why, some of those new birds arent much more sophisticated than a Fourth of July firecracker, and all you can do is point and shoot. But they work, with nearly a hundred percent reliability. And were getting the job done
To Bud, Siobhan supposed, this mighty space project was a boyhood dream come truespace engineering fast and brutal and efficient and on a massive scale, the way it used to be, before cost and politics and risk aversion got in the way.