Lasers demonstrate how oxygen was created before life evolved on earth

Graduate student Zhou Lu at the University of California, Davis, has shown that it is possible to form oxygen using a high-energy vacuum ultraviolet laser to excite carbon dioxide.

This process could be happening naturally right now, taking place in the Earth’s upper atmosphere, where vacuum ultraviolet light from the sun hits Earth.
 

It was previously thought that the formation of oxygen in the absence of life forms was a more complicated process.

 

“Our results indicate that O2 can be formed by carbon dioxide dissociation in a one-step process,” Zhou said.

 

Zhou worked with professors in the Departments of Chemistry and of Earth and Planetary Sciences. Funding came from NASA, the National Science Foundation (NSF), and the US Department of Energy.

 

Around one-fifth of our planet’s atmosphere is made up of oxygen, which is produced by green plants during the process of photosynthesis.

 

Previous research indicated that earth’s air—before the evolution of photosynthesizing organisms—was made up mostly of carbon dioxide, methane and nitrogen.

 

It was speculated that there was a small amount of “non-life” oxygen in the atmosphere even before the appearance of photosynthesis-capable organisms, but have been unable to answer definitively where the “non-life” oxygen came from.

 

“Our results indicate that O2 can be formed by carbon dioxide dissociation in a one step process,” Zhou said. “The same process can be applied in other carbon dioxide dominated atmospheres such as Mars and Venus.” — TJD, GMA News