Meteor impacts on Earth could have transmitted life to other planets

BBC : The theory of panspermia suggests that microbial life could survive in the extreme conditions of outer space. Hidden in the rocky debris of planetary collisions, microbes could travel between bodies in the solar system and then find suitable environments in which to grow. Rachel Worth of the Pennsylvania State University and her colleagues have estimated the amount of debris ejected from Earth by collisions with asteroids over the last 3.5 billion years. They then calculated likely trajectories and sizes of the debris. Any rocks larger than 3 m were assumed capable of shielding microbes from solar radiation. Most of the debris fell back to Earth or into the Sun, but a sizable fraction of the debris could have collided with other planets or moons, some of which, like Mars and Europa, are believed to have been capable of supporting life. Worth’s group says that if ancient microbial life is found on other bodies in the solar system, it is possible that it originated on Earth.