Archaeaology
Panspermia
She lives in the warm seep, where the iron-rich water boils up between basalt grains and the sky is a pale butter color through the shallow flood. She is one cell. She has never been anything else. Her membrane is laminated with strange lipids that hold their shape at temperatures that would unmake any softer thing, and inside her, sulfur-loving machinery clicks through its work, pulling energy from the volcanic breath of the world.
She does not know she is on Mars. She does not know there is anywhere else.
The seep has been her whole life and the whole life of her mother and her mother’s mother, back through a chain of divisions older than the floodplain itself. The Tharsis volcanoes exhale to the west. The young sun, weaker then, throws a bronze light across the silt. She drifts. She feeds. She doubles, and her daughter drifts away from her into the same warm water and does the same.
Then the sky turns white.
The meteor arrives without warning. It is the size of a small mountain and it is moving at thirty kilometers a second and it strikes the floodplain not far from the seep. The shockwave outruns sound. The water above her flashes to steam and the steam itself is vaporized and the basalt beneath her splits and lifts. She is inside a chunk of rock the size of a fist, and the chunk of rock is inside a plume of ejecta the size of a country, and the plume is moving fast enough to leave the planet entirely.
She does not register any of this as event. She registers it as chemistry. The water around her becomes pressure, then heat, then nothing. Her lipid membrane stiffens. Her sulfur enzymes fold inward and lock. A heat-shock response that her lineage developed for hydrothermal flares triggers across her cytoplasm, and a sheath of protective proteins crystallizes around her DNA. She enters a state her descendants will one day be named for: extremophile dormancy, the slow patient waiting of a cell that has decided not to die.
The rock she is in clears the thin Martian atmosphere and keeps going.
For a time she is inside a stone the size of a fist, tumbling through vacuum. The cosmic rays come for her DNA and her protein sheath absorbs most of them and her repair enzymes, queued and ready, fix what gets through. The temperature outside the rock cycles between sun-facing scorch and shadow-facing absolute cold, and three centimeters of basalt mute the swing to something her dormancy can tolerate. She does not metabolize. She does not divide. She is a sealed envelope of intention, addressed nowhere, carried by orbital mechanics into an inner solar system that does not yet know it has been mailed.
The blue planet rises in her rock’s path.
Atmospheric entry strips the outer two centimeters of her stone in a long bright streak across a sky no eye yet exists to watch. The basalt around her glows. The temperature gradient passes through her lipid laminate so fast that the inner layer never quite reaches the threshold that would denature her, and then the rock is through, the rock is in air, the rock is falling. It hits the ocean and the ocean closes over it and the heat hisses out into water that is hot but not impossibly so, water thick with iron and sulfur and a faint sweet broth of organic chemistry that any of her ancestors would have recognized.
The rock sinks. It comes to rest on a slope of black sediment near a vent that exhales the same volcanic breath as her seep, three hundred million kilometers and many months ago. Her membrane softens. Her enzymes unfold. The crystallized sheath around her DNA dissolves back into the cytoplasm it came from. She tastes the new water and finds it acceptable.
She drifts out of the cracked rock and into the current.
Something else is already here. It is smaller than she is and it is built differently, a tight little package with a single loop of DNA and no protective sheath at all, drifting and feeding the way she drifts and feeds. She closes around it. Her membrane folds it inward, the way her membrane folds inward around any useful chemistry. She does not eat it. She houses it. The little package settles into her cytoplasm and keeps doing its own work, and her work continues alongside it, and the two sets of machinery do not interfere.
She doubles. Her daughter drifts away into the warm water and does the same.