WASHINGTON, Aug. 8 (UPI) -- U.S. researchers say building blocks of genetic material reach Earth from extraterrestrial sources, and in greater quantity than previously thought.
Scientists at the Carnegie Institution say chemicals that existed in the early solar system, and may have been a pivotal source of organic compounds that gave rise to life on Earth, have arrived on our world in a type of organic-rich meteorite called carbonaceous chondrites.
The researchers used advanced spectroscopy techniques to purify and analyze samples from 11 different carbonaceous chondrites, an institution release said Monday.
They found a diverse array of nucleobases and compounds that are very rare in terrestrial biology and were not found in soil and ice samples from the areas near where the meteorites were collected.
"Finding nucleobase compounds not typically found in Earth's biochemistry strongly supports an extraterrestrial origin," Jim Cleaves of Carnegie's Geophysical Laboratory said.
The findings suggest the earliest forms of life on Earth may have been assembled from materials delivered to Earth by meteorites, the researchers said.
"This shows us that meteorites may have been molecular tool kits, which provided the essential building blocks for life on Earth," Cleaves said.