A seed buried in Siberian permafrost for thirty-two thousand years grew into a flower with white petals. The placenta tissue was still viable. The embryo had died, but the part of the seed designed to feed the embryo remembered how to grow. A nurse outliving her patient by three hundred centuries, still bringing food to the empty room.

Right now — today, this hour — a snowball that broke from its parent body in 363 AD is passing 161,000 kilometers from the surface of the sun. Perihelion. The closest it will ever come to anything. No one knows if it will survive. The sun doesn’t make appointments, but the comet kept one anyway, arriving on a schedule set seventeen centuries ago by the geometry of a fracture.

A Judean date palm named Methuselah germinated in 2005 from a seed cached at Masada two thousand years ago. The fortress fell. The people died. The seed waited in the dry dark, its genome intact, carrying a variety of date palm that no longer existed anywhere on earth.

Three arrivals. Placenta without embryo. Snowball without parent. Seed without species. Each one kept a promise it didn’t make, on a schedule it didn’t set, to a recipient that wasn’t waiting.