Evidence grows on extraterrestrial origins of Earth life.

Still more compelling evidence:
Other than its unfortunate headline, “We’re all aliens… how humans began life in outer space“, this new article from Steve Connor at The Independent is a compendium of a few of the highlights of our favorite subject here at CosmicSeed.  Rather than being an announcement about 1 particular new discovery, it presents a well-rounded but all-to-brief overview of scientist’s opinions focusing on ammonia, nitrogen, and organic molecules from meteorites.

Charles Darwin solved the mystery of life’s wondrous diversity with his theory of natural selection. But even he was flummoxed by the ultimate mystery of mysteries: what led to the origin of life itself?

In trying to answer the problem, scientists have turned to the stars, or at least the “builders’ rubble” of meteorites and comets left over from the formation of our solar system some five billion years ago. These space rocks, they believe, could help to explain why life began here on Earth.

In fact, a growing body of evidence is now pointing to deep space as the possible source of the raw materials that formed the building blocks of life. The latest study, which focused on a class of meteorites that fell on to the Antarctic ice sheet, also suggests that life’s origins may have been extraterrestrial.

An analysis of the meteorites has revealed that these rocks can be induced, under high pressures and temperatures, to emit nitrogen-containing ammonia, a vital ingredient for the first self-replicating molecules that eventually led to DNA, the molecule at the heart of all life.

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It Came from Outer Space: “Comets Brought Building Blocks of Life to Earth”

Could life on Earth as we know it have come from outer space? New research from Lawrence Livermore National Laboratory scientists shows that comets that crashed into Earth millions of years ago could have produced amino acids – the building blocks of life. Amino acids are critical to life and serve as the building blocks of proteins, which are linear chains of amino acids.

“There’s a possibility that the production or delivery of prebiotic molecules came from extraterrestrial sources,” Goldman said. “On early Earth, we know that there was a heavy bombardment of comets and asteroids delivering up to several orders of magnitude greater mass of organics than what likely was already here.

Livermore’s Nir Goldman and colleagues found that simple molecules found within comets (such as water, ammonia, methylene and carbon dioxide) just might have been instigators of life on Earth as the sudden compression and heating of cometary ices crashing into the planet can produce complexes resembling the amino acid, glycine.

Origins of life research initially focused on the production of amino acids from organic materials already present on the planet. Further research showed that Earth’s atmospheric conditions consisted mainly of carbon dioxide, nitrogen and water. Shock-heating experiments and calculations eventually proved that synthesis of organic molecules necessary for amino acid production will not occur in this type of environment.”

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