Indiatimes.com- 6/5/13
Thanks to: http://soundofheart.org/galacticfreepress/content/life-producing-phosphorus-carried-earth-meteorites

Washington: A team of scientists has finally solved a 3.5 billion-year-old mystery showing that phosphorus – key element that produced life on Earth- was carried to Earth on meteorites.
The scientists led by a University of South Florida astrobiologist found that during the Hadean and Archean eons – the first of the four principal eons of the Earth`s earliest history – the heavy bombardment of meteorites provided reactive phosphorus that when released in water could be incorporated into prebiotic molecules.
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