The Gun

In The Gun, by Philip K. Dick, nothing moved or stirred, everything was silent and dead, and only the gun showed signs of life. The Captain peers into the eyepiece of the telescope and says "It was an atomic fission we saw, all right." Dorle, the Chief Navigator, asks "Why did we come all this way, then?" and says "There's no point even in landing."

The Captain slides back the port window so that the surface of the planet under them is visible, and mile after mile of unbroken ruin stretches out, blackened slag, pitted and scarred, and occasional heaps of rock. Nasha jumps and tells the others to look over there, at the edge, where they see a circle of dots, white pellets on the dead skin of the planet. Dorle laughs and says no one fires the gun, because "It fires itself," and that it is "alert to anything that flies or moves above the ground level."