Phrenotopia | Alternative Biospheres: Mars-class worlds #astrobiology #evolution #alienbiospheres @Phrenotopia | Uploaded 2 weeks ago | Updated 18 hours ago
Mars-class worlds are terrestrial and temperate worlds too small to retain a thick atmospheric blanket and an active geology.
As frozen, irradiated deserts, any Life they may have hosted at the surface would be forced into the underground.
A planet like Mars was too small and therefore, because of its greater surface to volume ratio, was losing heat too quickly.
This ground down Mars geology to a halt and with it a protective magnetic field.
Given how quickly Life arose on Earth it is not implausible that it likewise did on Venus and Mars only for it to get snuffed out again or pushed into refugia.
Methane detected on Mars may hint at Life persisting deep in the underground.