A massive bombardment of meteorites billions of years ago could have brought in enough water and carbon dioxide to jump-start the chemistry that let the Earth develop into the garden spot of our solar system.
This isn't the first time scientists have theorized that the ingredients for life on Earth could have been delivered. Comets and asteroids both have been proposed as carriers of water as well as organic compounds to Earth.
What distinguishes the new research, published in the earth and planetary science journal Geochimica et Cosmochimica Acta, is its suggestion of when and how the Earth received its shipment of life-giving material.
The incident at the heart of the study is known as the Late Heavy Bombardment, a time about 4 billion years ago, not long after the Earth was formed from the dust and debris swirling around the young sun.
clipped from: www.latimes.com