“Nanotech is on our own horizon,” insisted Alfred. “We can manipulate atoms with microscope probe elements, we can use the amino acids to make new, non-natural proteins. We can posit self-replicating assemblers that can take inexpensive raw materials — any hydrocarbon feedstock would do — and produce anything from a rocket ship to a disease-fighting submarine that would roam your bloodstream—”

David Petit slammed the table with the palm of his hand. “Nonsense,” he said. “Sure you can manipulate atoms. You can even get them to hold still for a while. But only by cooling your sample down to liquid helium temperatures. At room temperature, the atoms of your assemblers will start combining, with the ambient air, water, with each other, whatever medium your assemblers are floating in.

“And what about the laws of thermodynamics? What about information flow? How do these assemblers get their information about which atom is where, in order to manipulate them? How do they know where they are themselves, to get from their tiny supply depots to wherever they are supposed to be working? How do they get their power for breaking up material, and navigating, and computing?” He turned to Bromwich. “Admiral, this is just more nonsense. Nanotechnology is cargo cult science. A plot generator for lazy sci-fi writers. Nobody has demonstrated any of this, outside computer simulations, where of course you can do anything you like.”

Evidently, Monica thought, watching him, the good doctor has a beef against nanotech. She wondered which grant application of his had been turned down in favour of some sexy nano-proposal.

Henry said mildly, “I’m not here to defend nanotech. The Moonseed, however, is doing one simple thing: building inward, and smaller. The structure, in fact, seems to be similar on all scales. You don’t need much stored information, or computation, or materials transfer to achieve that.”

The Admiral frowned. “I wish you scientist types wouldn’t argue with each other. So the Moonseed is some kind of artificial phenomenon. We’re looking at tiny machines here. Is that what you’re saying?”

Henry said, “Maybe they are artificial. Maybe they are alive. It may be that when a life form is sufficiently advanced, there is no difference. It may not matter anyhow.”

Bromwich shook her head, visibly angry, dissatisfied at the speculation and lack of clarity. “Continue with your analysis,” she told Henry. “What’s this thing for? What’s the point of rebuilding a rock?”

“Concentration of energy,” Henry said.

“What?”

“There is enough chemical energy in a tank of gasoline to achieve unified-theory levels of energy density — if all the energy could be applied to a single proton. Which we can’t achieve. We build colliding accelerators miles long to try to emulate that, but we don’t even come close, not within orders of magnitude.”

Bromwich pulled her lip. “You’re saying these little critters turn lumps of rock into — uh — miniature particle accelerators.”

“That’s exactly it, Admiral.”