Early life probably fell victim to massive space rocks
Planet-sterilizing asteroids struck Earth until around 4.3 billion years ago

PUMMELED PLANET Colossal rocks pelted Earth during the planet’s early years, annihilating any emerging life and creating magma-gushing gashes (red), as seen in an illustration. Scientists now estimate that the final Earth-sterilizing object hit 4.3 billion years ago.
S. Marchi
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