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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?

In the Beginning: Formation of the Solar System

4.5 billion years ago

The Milky Way galaxy
The Milky Way galaxy
 
It's believed that the solar system was formed when something, possibly the shock of an exploding star or a stellar cloud collision, disturbed an enormous cloud containing dust and cold gas, and compressed it until it collapsed inward from the force of gravity.

This big squeeze created the Solar Nebula, a giant cloud of material that is believed to have spawned our solar system. As the Nebula collapsed, its temperature and rotation increased. The increased spin began to flatten the nebula, pressing atoms and molecules together into particles. The hottest point, right at the center, became the Sun. Cooler particles spread to the outer regions and eventually formed planets and moons.

Meteors are thought to be pieces left over from the formation of the solar system and some meteorites have been dated at 4.5 billion years old.


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