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Exploring Space - The Quest for Life Exploring Space - The Quest for Life Exploring Space - The Quest for Life
Meteorites and Life - The Possible Relationship to Life

Did We Come From Comet Dust?

Crumbs of Creation: Formation of the Oort Cloud

Slightly less than 4.5 billion years ago

Artist's rendering of the Oort cloud
Artist's rendering of the Oort cloud
 
The Oort cloud is believed to be a potential source of meteorites that fall to Earth. During the planet formation process, smaller objects — including asteroids and comets — were drawn to the outer edges of the solar system. These became an immense cloud called the Oort cloud.

Every 225 million years, the solar system, with its sun, planets, stars and Oort cloud, circles the Milky Way galaxy. The stars don't follow the same orbit and sometimes come into close contact with the cloud, the sun or other stars. These close encounters can disturb the Oort cloud and spin comets directly into Earth's path.


Back Introduction 4.5 billion years ago  - In the Beginning: Formation of the Solar System less that 4.5 billion years ago - Crumbs of Creation: Formation of the Oort Cloud less that 4.5 billion years ago - More Crumbs of Creation: Formation of the Asteroid Belt May 1848 - Louis Pasteur's Discovery: The Design of Life Feb. 1953 - Stanley Miller's Experiment: Sparking the Building Blocks of Life Sept. 28, 1969 - The Murchison Meteorite Meets Earth Feb. 14, 1997 - Discovering a Left-Handed Link to Space: Amino Acids Found in Meteorite Dec. 20, 2001 - A Sweet Discovery: Sugars Found in Murchison Today - The Research Continues Next