More Evidence that Life First Came from CometsS

Many people believe the seeds of life on Earth came from someplace else — but there's always been a huge stumbling block for this theory. Any amino acids carried on a meteor would have needed to survive the intense journey through the Earth's atmosphere, in order to be the origin of life on our planet.

But now, new research has shown the building blocks of life might not just have lived through the journey — it might have triggered their transformation.

Top image: Comet Hale-Bopp, photographed by Kevin Dooley/Flickr.

New research by NASA is being presented at the ACS Spring Meeting, and lead researched Dr. Jennifer Blank and her team have shown that the amino acids we know are on board meteoroids can survive the trip to becoming meteorites.

Blank's research team simulated the trip the amino acids would have taken through the atmosphere by blasting them with a gas gun, a device capable of shooting a high-pressure shot of gas at supersonic speeds. The amino acids would have been protected by being on the interior of the comets, and the heat and shock of the trip and impact was not enough to break them down. In fact, pressure from the impact apparently counteracted the intense heat and even supplied the energy needed for the amino acids to start forming peptide bonds, allowing the creation of proteins. That's right, the crash could be what triggered their transformation into a more complex form.

These experiments, coupled with computer simulations, lead the team to think that Earth could very well have been seeded by life from the skies, possibly even multiple times.

"Our research shows that the building blocks of life could, indeed, have remained intact despite the tremendous shock wave and other violent conditions in a comet impact," Blank said. "Comets really would have been the ideal packages for delivering ingredients for the chemical evolution thought to have resulted in life. We like the comet delivery scenario because it includes all of the ingredients for life - amino acids, water and energy."