Living underneath an orbital defense cannon was interesting. The geostationary satellite cast its shadow elsewhere, most of the day, but Fred always made sure he was outside when it passed through his town. He’d been a child when they first put it in orbit, but he still remembered just how safe he’d felt, knowing it was up there.

Now, he just liked sitting in the shade and marveling at human ingenuity. In two generations, they had gone from launching orbital defense cannons to no longer needing them. They’d become a last, defunct line of defense in a war that was over. Curios from a past that stuck around because they weren’t worth taking down.

Today, as the shadow passed overhead and Fred enjoyed his lunch, something about it seemed a little off to him. As he munched his way through a ham sandwich, he looked at the familiar dark outline about his head. It took him a couple of minutes to figure it out, but he eventually realized that the shadow seemed off because the various shapes in its profile were on the wrong sides.

It looked like someone had just spun the whole thing around. Fred pulled out his cell phone and pulled up the space transit blotter, looking for a reference of a satellite maneuver, like they do during maintenance. Today turned up empty.

After a few more searches left him empty-handed, Fred leaned back and watched the cannon again. It was clearly pointed down at Earth, rather than just rotated around on a different axis. Suddenly, the looming shadow around him wasn’t the constant comfort it once was. It felt like he was sitting, eating a boring sandwich during a break from a dead-end job, right underneath a gun. One shot was all it would take to-