The Last Porchlight in M88

Cal Rusk lived on Mercy, a dry little rock on the far outer limb of M88, where the spiral arm thinned into dust, cold hydrogen, and bad decisions. His cabin leaned into the wind even though Mercy had no wind worth mentioning, just habit and pessimism. At night, Cal sat on the porch with a tin cup of engine coffee and watched the galaxy curve overhead like a silver lariat, all those inner stars crowding around the bright nucleus where the big black hole sat fat and patient, eating whatever strayed too close. Out here, though, things were quiet. Quiet enough to hear the pump complain. Quiet enough to hear the stars go missing.

The first sign was the cattle. Not real cattle, because real cattle had given up on Mercy generations back, but gas skimmers, long-legged machines that grazed the upper atmosphere and bottled hydrogen for the settlement. They started coming home light. Then they stopped coming home at all. Cal rode out in his pressure buggy with a rifle, a coil of tow cable, and the deeply held belief that any problem in the universe could be fixed by either hitting it, hauling it, or insulting it until it got embarrassed and left. What he found past Arroyo Crater was not rustlers. It was the edge of the Virgo Cluster itself, invisible and enormous, scraping M88’s outer pastures clean.

The scholars back in the inner arm called it ram pressure stripping, which sounded to Cal like something invented by men who had never had their livelihood peeled off a planet one molecule at a time. M88 was falling through the cluster medium on its long road toward M87, and Mercy was on the wrong side of the wagon. The cold gas was being pushed inward, away from the frontier, toward the glowing towns and star nurseries nearer the galactic center. Cal stood beneath a sky full of hard blue stars and watched his world become the dry husk everyone in the cities had always assumed it already was. “Well,” he told the universe, “that’s a discourteous way to knock.”

So Cal did the only sensible thing a frontier idiot could do. He fired up the old orbital beacon, aimed it at the nucleus, and sent a message demanding compensation for stolen grazing rights. The reply came twelve thousand years later, which was faster than local government usually managed, and it arrived as a beam of tightly packed instructions from the central black hole’s accretion district. Cal’s descendants gathered on the same porch, translated the message, and read it twice before anyone spoke. It said: Claim approved. Herd successfully delivered. Frontier planet Mercy was established as a temporary collection station by your ancestor Cal Rusk, Acting Marshal, Outer Arm. Payment enclosed. Then the sky opened, and four hundred billion stars began depositing interest.

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