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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?

Discovering a Left-Handed Link to Space: Amino Acids Found in Meteorite

Findings published February 14, 1997

Molecular model of an amino acid.
Many left-handed amino acids were found inside the Murchison meteorite. Most were kinds not found on Earth.
 

Scientists found evidence in Murchison fragments that life-forming, left-handed amino acids may have originated in deep space. From deep within the meteorite, Dr. John Cronin and Dr. Sandra Pizzarello extracted amino acids not found on earth. These amino acids were predominantly left-handed, the kind that could give a kick-start to life.

So far, 92 different amino acids have been identified in the Murchison meteorite. Of these, only 19 are also found on Earth. The remaining amino acids have no apparent terrestrial source. This discovery led scientists to consider the possibility that Earth's life forms originated elsewhere in the universe. And the same cosmic process that may have helped life arise on Earth could also be seeding life elsewhere in the universe.


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