No collision, no life: Earth probably needed supplies from space - Phys.org

1. No collision, no life: Earth probably needed supplies from space  Phys.org
2. Cataclysmic crash with neighboring planet may be the reason there's life on Earth today, new studies hint  Live Science
3. Life on Earth might not have emerged without a great collision  Universe Space Tech
4. A Mars-Sized Planet Crashed Into Earth — And Created Life As We Know It  The Daily Galaxy