It's a mystery that has plagued scientists for a while, but no more.
Scientists claim to have cracked the code on a mystery that has been nagging them for a while now: where is all the carbon that’s supposed to be here?
They now have a culprit ultraviolet rays from the sun have been forcing carbon dioxide out of the atmosphere, finally putting that puzzling mystery to bed, and scientists couldn’t be happier, according to a Business Standard report.
Mars doesn’t have a thick, protective atmosphere like us — its atmosphere is mostly a thin layer of carbon dioxide which is unable to keep water from freezing or evaporating. But at one point in its history, Mars was a pretty warm and moist place, scientists believe.
“Our paper shows that transitioning from a moderately dense atmosphere to the current thin one is entirely possible,” Caltech postdoctoral fellow and lead author Renyu Hu said in a statement. “It is exciting that what we know about the Martian atmosphere can now be pieced together into a consistent picture of its evolution — and this does not require a massive undetected carbon reservoir.”
That’s why for years, even though scientists knew that the sun would have stripped much of the carbon out of the atmosphere by now, they still expected a lot more carbonate in the Martian rocks. But measurements indicate that the Martian atmosphere has far more carbon-13 than carbon-12, but why?
The scientists think it began with UV light from the sun first splitting carbon dioxide in the upper atmosphere into carbon monoxide and oxygen, and then further splitting the carbon monoxide into carbon and oxygen. Some of the carbon atoms then had enough energy to escape the atmosphere — in this case, carbon-12 had more energy than carbon-13.
Not only does this close the book on that mystery, it could help them better calculate what the atmosphere looked like 3.8 billion years ago, and just how similar its atmosphere was to Earth’s today.