—The Quebecois said you have a plan.
—I do. Half of one anyway.
—That’s a half more than what we had an hour ago.
—I suppose so.
—Well? What are you waiting for? We don’t have all day!
—Yes, sir. You know I’ve been going through everything we learned about the metal these robots are made of. There are slight differences, but it’s essentially the same material they built Themis with. It’s an alloy, mostly iridium, and it has a bunch of properties we can’t explain but that we’re beginning to understand. For example, we know it’s able to store energy. We don’t really know how it works, but we can make things with similar properties. We can make metal that stores solar energy and releases it when we want it to. We turn ruthenium into fulvalene diruthenium. That will store reasonably large amounts of solar energy that can be released using a catalyst.
—Ruthenium … Isn’t there some of that in the metal that makes up Themis?
—There is, but in very minute quantities. Nothing that could explain what it does. And the metal in Themis actually prefers nuclear energy. It can store a phenomenal amount of power. The closest thing we have is something like uranium. We can’t make it do what the metal in Themis does, but uranium does store energy and releases it over time. It’s slow if you don’t do anything to it, but it’s enough to keep the Earth cooking. About half of the heat inside the planet comes from radioactive decay. We have little control over the amount of energy uranium releases and the speed at which it does, but if we create a fission chain reaction—in a nuclear reactor, for example—we can release a lot more energy, and a lot faster.
Anyway, I decided to think of it as uranium, see where it would lead.
—And?
—It gave me an idea. There’s this special kind of bacteria, Geobacter. They have tiny wires on them—they’re called pili—that insulate them from the toxic environment they live in, and they’re able to transfer electrons to radioactive metal and change its properties. Basically, they can clean up radioactive waste, turn radioactive metal into a mineral by changing its molecular structure. It’s a slow process, though, way too slow. Takes years for these things to eat just a tiny bit of radioactive waste.
There’s a lab at Michigan State—it’s run by a Dr. Lina Texera. They play with a particular kind of these bacteria, Geobacter sulfurreducens. They were able to increase the strength of the pili and make them more efficient. Basically, they added armor to the bacteria, made them more resistant so that they can mineralize uranium a lot faster.
It sounded promising. Even with some superarmor, it would take forever for these things to colonize something as big as the alien robots, but I thought it was worth a shot. Anyway, I called her. Nice woman. She called me Rose, said we met at a conference before—must have been before I died. I had her send over a sample by helicopter.
It’s really disgusting, green, gooey stuff. I wasn’t sure what to do with it. Anyway, I put on two pairs of gloves, one on top of the other, I took the little shard we had chipped off one of the panels and rubbed some of that goo on it with a Q-tip. The plan was to expose it to radiation and see if it would take longer to saturate and discharge, maybe release less energy, something. I let it rest on a block of plutonium for a good hour, I couldn’t get it to release anything at all. The last time I had tried that, it took only ten minutes to destroy half my lab.
I tried a few drops of the mixture on one of the panels. Nothing happened. I put some of it under the microscope and all the bacteria were dead. So I took the whole thing—about a cupful of it—and just poured it on the panel. It didn’t do anything at first, as I expected. I figured I’d come back later during the day. I turned off the light on my way out, then I noticed that the turquoise light in the symbols was wavering. Just a bit at first, then a little more. After about five minutes, the panel went completely dark. That was two hours ago and it hasn’t turned back on.
Whatever makes that metal do the things it does, it must be a very fragile equilibrium. I think the bacteria just throws it off balance, enough to make it stop functioning.
—So that’s your plan? Throw some green goo at the robot— —At one of them, yes.
—When you got back from Washington, you told me you believe these aliens are waiting for us to demonstrate that we could be just as evolved if they hadn’t messed with our gene pool.
—Yes. I could be wrong, of course.
—So the idea is to beat them without using anything that didn’t exist before they showed up thousands of years ago.
—That’s what I’m running with.