Mars' Organic Matter Unveils Life's Building Blocks Origins

In the vast expanse of a meteor crater on Mars, a solitary robot is diligently operating. Its current task involves drilling into the Martian soil and collecting samples with its robotic arm - an activity it has grown accustomed to over the years. This lone explorer, NASA's Curiosity rover, has been actively studying Mars for almost 12 years now, acting as an extended arm of science and consistently making discoveries that challenge our understanding of both Mars and Earth. 

Recently, Curiosity discovered sedimentary organic material with unique properties that left many researchers perplexed. The carbon-based materials exhibited peculiar ratios of carbon isotopes which usually indicate microbial life on Earth but can also be products of non-biological chemical processes. Researchers have yet to determine what caused these specific conditions on Mars. 

However, this discovery was met with excitement rather than confusion by a group of researchers from the University of Copenhagen and Tokyo Institute of Technology who recently published their findings in Nature Geoscience. According to co-author Matthew Johnson, this finding was "the smoking gun" needed to confirm his decade-old theory about photolysis taking place in Mars' atmosphere. 

The data obtained from Curiosity’s sample enabled them to substantiate their claim that billions of years ago sunlight broke down CO2 in the Martian atmosphere into simpler molecules like carbon monoxide which then reacted further forming complex organic compounds essential for life. 

Johnson explained how their research showed that atmospheric photochemical reactions could produce such organic material without any biological process involved – akin to creating 'eggs' before chickens even existed! However, whether these building blocks eventually led to life remains unknown. 

With similar CO2-rich atmospheres existing during early planetary history across Earth, Venus and Mars when photolysis occurred extensively; Johnson believes these findings could provide critical insights into how life originated on Earth too! 

Twelve years prior Johnson along with two colleagues used quantum mechanics-based simulations predicting outcomes when UV light from the Sun interacts with CO2 rich atmospheres leading to photolysis. They deduced that approximately 20% of CO2 would dissociate into oxygen and carbon monoxide, with the latter containing lesser amounts of heavier isotope Carbon-13 due to preferential photolysis of lighter Carbon-12. 

This led them to predict specific ratios for these isotopes post-photolysis providing distinct fingerprints for identification. One such fingerprint was found years ago in a Martian sample. 

Interestingly, this sample was part of a meteorite named Allan Hills 84001 which had landed on Earth after being ejected from Mars due to another meteor impact! The carbonate minerals present in it formed from atmospheric CO2 showed exactly the predicted ratio between carbon isotopes! 

The complementary nature between this enriched presence of Carbon-13 in Allan Hills and its depleted levels in Curiosity’s organic samples further strengthened their theory linking two samples believed to have originated during Mars’ infancy yet found over 50 million kilometers apart! 

With no other explanation fitting both enrichment and depletion patterns relative to volcanic CO2 emissions on Mars (which follow similar compositions as Earth's volcanoes), Johnson believes they've traced back the source of carbon within Martian organic material all the way up to photochemically produced carbon monoxide! 

While researchers hope for finding similar isotopic evidence on Earth, our planet's dynamic geological evolution could pose significant hurdles unlike relatively unchanged surfaces like those on Mars. Regardless, Johnson finds solace knowing we’ve taken one big leap towards understanding life’s origins by discovering its building blocks' formation process - at least on Mars!