Modeling Lithopanspermia: Earth-Derived Material Reaching Europa and Enceladus Is Extremely Small, Indigenous Life Most Likely
To the point
Life in the buried oceans of moons like Europa and Enceladus would most likely be native to those worlds rather than seeded from Earth or Mars, because the odds of microbes hitchhiking on rocks reaching them are vanishingly small, would take billions of years, and would face deadly high-velocity impacts.
