The results of a new study carried out by a team of scientists theorize that the molecular building blocks that support life on Earth began in outer space.
The research was conducted by a team of scientists from the University of Sherbrooke and produced surprising results. The round of experiments reveals, essentially, that organic molecules—among them ethane, propylene, and acetylene—are able to form under space-like conditions. The team simulated the conditions by creating a frozen vacuum of space and bombarding methane- and oxygen-rich frozen films with radiation. The presence of radiation in the harsh environments common to many of the planets in our Solar System allows organic molecules like these to evolve into a more complex form.
These tests show that the organic molecules formed in a way similar to those that appear on space dust and other interplanetary objects such as asteroids, comets and moons. The team took a close look at the impact of low-energy electron (LLE) irradiation. They were chosen for the simulation because the electrons are the result of high-energy radiation interacting with matter.
The study's findings appear in a report, titled "Synthesis of complex organic molecules in simulated methane-rich astrophysical ices", in this week’s Journal of Chemical Physics with the support of the American Institute of Physics (AIP). The panspermia theory, embraced by many in the scientific community—among them noted astrophysicist Stephen Hawking—holds that our planet was populated as a result of a cyclical transfer of microbes from a comet hitting Earth.
These experiments represent another step in proving this theory, which has been gaining more and more attention in the scientific community in the past two decades. The University of Edinburgh Astrobiologist and Professor Charles Cockell, who was not involved in the study, said about the impact of the research: “I think this study is interesting because it’s another pathway to produce organic molecules that are made more complex by radiation.”
“What these experiments show is that even at the extremely low temperatures of interplanetary or interstellar space you can get chemical reactions occurring that lead to more complex organic compounds,” said Professor Cockell.
Though he acknowledges that the study is very promising, Professor Cockell also admits that there is still more research to be done to provide clearer answers: “It’s still up in the air– people are starting to realise there may not be a special place where [organic molecules] form,” he said, adding that we should reserve a bit of healthy skepticism when forming theories about the origins of life, “It’s not as if the organics for life had to come from one place, and I think people are beginning to realise they were probably being formed on the early Earth, and potentially raining in from space as well.”
The biggest draw of the field of cosmology is that definitive—yet incomplete—answers about the origins of life on Earth can be given, and are accepted. One discovery answers a group of questions, and simultaneously creates a whole new set of questions for future scientists to solve.