Halite salt crystals from the Monahan and Zag meteorites that landed on Earth some 20 years ago both contained organic matter like liquid water, hydrocarbons, and amino acids.
Scientists believe that this discovery leads to the conclusion that the origin of life is possible elsewhere. The traces of water in both meteorites are direct evidence of the chemical makeup of a water-rich world in the outer solar system.
"Our coordinated organic analysis of the salt crystals suggest that the organic matter originated from a water-rich, or previously water-rich parent body -- an ocean world in the early solar system, possibly Ceres," said planetary scientist Queenie Chan, study author and postdoctoral research associate at The Open University in the UK.
The Origin Of Life As We Know It
The elements found in the crystals are significant organic ingredients that can lead to the origins of life. The scientists likened the discovery to a fly in amber.
While the discovery does not conclude that life existed outside of Earth, the presence of organic matter in the salt crystals raises the possibility of trapping prehistoric life and biomolecules in the meteorites.
"This is really the first time we have found abundant organic matter also associated with liquid water that is really crucial to the origin of life and the origin of complex organic compounds in space," added Chan.
Extensive analysis of the salt crystals also revealed the probable origins of the meteorites, including the dwarf planet Ceres and asteroid Hebe as major objects in the asteroid belt. Similarities of the crystals found in the meteorites are also structural clues the two might have collided with each other and mixed fragments and materials.
Monahans And Zag Meteorites
It took scientists almost two decades to comprehensively analyze samples from the pair of meteorites that were believed to have existed some 4.5 billion years ago.
Monahans meteorite landed in Texas in March 1998 while the Zag meteorite on a mountain in the vicinity of Zag, Morocco in August of the same year. Samples from the space rocks were preserved at the NASA Johnson Space Center.
The in-depth analysis of the millimeter-sized salt crystals from the meteorites took time to complete because scientists needed a highly-sensitive instrument to study the crystals of amino acids at nanoscopic scales.
The required technology was not yet available at the time when the meteors were discovered. Back then, only liquid water was found in the two meteorites.
Experiments on the salt crystals were conducted in the cleanest laboratories of the NASA Johnson Space Center to avoid the contamination from foreign elements such as dust in the air.
The Science Advances published the abstract of the study.