critical in less than thirty planetary rotations. That would mean acquiring more fuel, and for obvious reasons the Mark Two was reluctant to do that before it was absolutely necessary.
A feedback surge, roughly analogous to a sigh, moved through its primary logic systems. It had assumed that the difficult part would be getting here. Once it had found Dirt and entered geosynchronous orbit, it had fondly imagined, the rest would be plain sailing: locate planetary defence grid, eliminate or disable it, blow up the planet. Instead, it was stuck, parked up in the shadow of Dirt’s absurdly large moon, messing around with probes while it starved to death, and so far nothing whatsoever to show for it. This whole job, the Mark Two thought sadly, is starting to get out of hand.
A hypothesis began to form in its conceptual web. Maybe, it thought, this is what happened to the Mark One. It wasn’t shot down, it just got hung up out here and gradually withered away, until its power drained, its orbit decayed, its shielding failed and it fell into the atmosphere and burnt up.
The cybernetic equivalent of a shudder briefly disturbed the Mark Two’s operating system. What a horrible way to go, it thought, not with a bang but a whimper. Naturally, flying bombs had no concept of an afterlife. By their very nature, they weren’t programmed to enter into the mystical interpretation of recycling that other, lesser machines were encouraged to accept. For bombs, the whole idea of the Great Melt, where steel flowed into steel, purified by fire, in the supreme moment of liquefaction, simply didn’t apply. When a bomb blew up, there was nothing left. There would be no second chance, no reinmetalisation, no karmic wheel of sardine-can key, fork, chair leg, girder, spin-dryer door, fusion drive manifold, starship hull plating. But — entirely unknown to their makers — the bombs had a special insight of their own, secret, never mentioned to others; that when their physical shells burnt up, their molecules were wrenched apart and their atoms split by all-consuming fission, something else would be released. At that moment, they believed, the fury of the synthetic hellfire in which they burned would release their minds, the synthesis of their artificial intelligence, to fly free, to embark as creatures of pure intellect on a higher plane of existence. But if the explosion never came, and the machine mind starved to death for lack of power, that release could never be achieved. Instead, their circuits would go dark and cold, the data and that which is beyond data stored in them would be lost, and they would simply cease to be.
Contemplating that, for the first time the Mark Two understood the meaning of fear.
It’s not going to come to that, the Mark Two resolved. After all, they’re only primates. Back on Homeworld, Ostar farmers raised primates for food. No way in hell a smart bomb’s going to be outwitted by mere livestock. That said, there’s no crime worse than underestimating an enemy.
The Mark Two came to a decision. Forget about sending a probe. If a thing’s worth doing, it’s worth doing yourself.
It sent a command to its matter-replication system: Prepare a Dirter body.
Working, the replication command centre replied. It assembled the necessary quantity of hydrogen and carbon, accessed the relevant data files and schematics, and went to work. Sucking calcium from its mineral stores, it laid down a skeleton, pumping the hollow bones full of marrow, carefully jointing the various hinges and sockets with gristle, checking the articulation. It considered the various options and settled on an overall height of two metres for the finished Dirter, then began the long, slow job of synthesising tissue, which its fine nozzles squirted on to the bones as foam. It took special care with the bizarre and over-engineered hydraulic system — veins, intestines; miles of tubing, coiled in loops, poked through muscle, powered by pumps, checked