Four billion years ago, Earth was hit by space rocks much more often than today. These impacts were very destructive, but scientists now think they might have helped life begin. New computer simulations show that when asteroids hit the young Earth, they created underground networks of hot water. These warm, wet places could have been where the first living things started.
Usually, we think of asteroids as dangerous, like the one that killed the dinosaurs. However, this new research, published in AGU Advances, looks at Earth's early history. When asteroids hit the planet's rocky surface, they created cracks deep underground. Liquids and vapors could then flow through these cracks. The heat from the impact, along with heat from inside the Earth, created warm water systems.
Scientists at the Southwest Research Institute used computer models to study this. They calculated how impacts made the Earth's crust porous, allowing water to circulate. They found that the top part of the crust was very porous about 4.3 billion years ago.
These underground hot springs could have lasted for thousands of years, giving simple chemicals enough time to form the complex molecules needed for life. Because the early Earth was hit so often, these warm, wet areas were common. Instead of just causing damage, the asteroid impacts helped create places where life could begin and grow. This research suggests that the same events that caused destruction also helped create the conditions for life.