Something had been broadcasting radio signals from the moon since before the dinosaurs. Not speech, but prime numbers and other patterns that no natural source could possibly produce. When we figured out how, the first flight to the moon was sent to visit the outsider. The lander camera showed a spiky coral reef of glistening black, hundred-meter long needles that waved slowly as if in an underwater current.

The astronauts approached it to bring our message of peace and understanding between sentient beings, and the ground swallowed them. We wondered if it had been an accident, but the still running camera recorded the thin black tendrils that regurgitated the dissected parts of the men out of the hole after a quarter of an hour. We could only speculate, but I think the outsider was looking for something in our bodies, or inside our cells, or in our brain structure, and we came up short.

After that, we only got up-close observations from the lone astronaut left on the orbiter, who survived for a week, reporting until his air ran out. Rifts started opening on the moon’s surface. The outsider seemed to have permeated the ground like some titanic fungus. Great pits the size of cities formed all over the surface, tens or hundreds of kilometers deep: gun ports for mountain-sized projectiles.

We managed to strike before the asteroid throwers were fully online. Our hastily built nukes obliterated the outsider’s site, but like an iceberg, the main part was hidden and unharmed. The counter-strike was coming. Even the most optimistic predictions said that the projectiles would sterilize the surface to a depth of several kilometers. Nothing of us, not even our DNA-based part of the phase space of life, would remain.

We decided that the only thing left for us was to give something else a chance to call this planet home, some time in the unimaginable future. We filled capsules with hardy spores and non-living viruses and prions that might serve as a template for self-replicating life and fired them into decaying orbits. We relied on sheer numbers, filling Earth’s orbit with a dandelion cloud that will come down over the eons. Some we threw into the depths of space to maybe reach another sun, mementos of our long forgotten world. For what it’s worth, we packed as much of human knowledge, art, and history engraved on metal sheets onto the probes as we could. Truthfully, nobody expects these to last or be comprehensible even if they are found.

As we watch the skies, waiting for the incandescent final curtain to fall, we dream of the beings that may follow in our footsteps. We hope you will know we lived and look back and feel some kinship with us. We, the extinguished, salute you.