It is fascinating to think that all the matter that we are made of, the organic material of our body, and of all living things on planet Earth, could have traveled for billions of years on the outer edge of the Solar System.
This is the conclusion of a study that has analyzed the chemical composition within tiny crystals inside two meteorites , which separately crashed on Earth in 1998. Two isolated space rocks that, however, have something in common: the ingredients for life.
They are the first meteorites studied to have so much liquid water and a mixture of complex elements, such as hydrocarbons and amino acids. A finding that implies not only that life on Earth has an ‘extraterrestrial’ origin, but the possibility that life is prevalent in other corners of the universe , even in our cosmic neighborhood.
It is the first comprehensive chemical exploration of organic matter and liquid water in salt crystals found in meteorites that impact the Earth.
The study not only delves into the narrative of the early history of our Solar System and the geology of asteroids, but presents exciting new possibilities for the existence of life elsewhere in Earth’s neighborhood.
The researchers analyzed the chemical composition within tiny blue and purple salt crystals taken from these meteorites. In addition, they include results of X-ray experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), which also found evidence of the mixing and past of the asteroid pair. According to the researchers, the origin of these rocks would be Ceres, a brown dwarf planet that is the largest object in the asteroid belt; or the asteroid Hebe, one of the most common sources of meteorites that fall on Earth.
The study, published in the journal Science Advances, provides the first comprehensive chemical exploration of organic matter and liquid water in salt crystals found in meteorites impacting Earth.
According to Dr Queenie Chan, planetary scientist and researcher at the Open University in the UK and lead author of the study: “This is the first time that we have found abundant organic matter associated with liquid water really crucial to the origin of life. and the origin of complex organic compounds in space ”.
“The organic matter was similar to that found in early meteorites, but contained more oxygen. Combined with other evidence, the results support the idea that organic matter originated from a parent organism rich in water or previously rich in water. water: an ocean world in the early Solar System, possibly Ceres. “
If life existed at all in the early solar system, the study notes that these salt crystal-containing meteorites increase the “chance of trapping life and / or biomolecules” within their salt crystals. The crystals carried microscopic traces of water believed to date from the infancy of our Solar System, about 4.5 billion years ago.
Organic matter ‘transshipped’ between asteroids
The similarity of the crystals found in the meteorites – one of which crashed in Texas in March 1998 and another near Morocco in August 1998 – suggests that their asteroids may have crossed.
There are also structural clues to an impact, perhaps from a small asteroid fragment that impacted a larger asteroid.
This opens up many possibilities for how organic matter can pass from one object to another in space , which would involve reconsidering the processes that lead to the complex set of organic compounds in these meteorites.
Image: Dr. Queenie Hoi Shan Chan
“Everything leads to the conclusion that the origin of life is really possible elsewhere,” says Chan.
The two meteorites that produced the 2-millimeter salt crystals were carefully preserved at NASA’s Johnson Space Center in Texas, and the tiny crystals containing organic solids and traces of water are only a fraction of the width of a human hair.
Reference: ‘Organic matter in extraterrestrial water-bearing salt crystals’. Science Advances (2018). advances.sciencemag.org/content/4/1/eaao3521
