As we continue our search for alien life form, scientists are still trying to find ways to identify alien life form outside Earth. Interestingly, researchers have now said that they have found a new chemical combinations which might help to indicate possible life activities on other planets.
In order to find the possible chemical combination, David Catling and his peers at the University of Washington examined Earth’s atmosphere during different time periods. As life forms have varied during different periods, Earth’s atmosphere also showed chemical imbalances. Interestingly, the researchers suggested that the chemical imbalance might have occurred due to biological activities which are the main source of substances which shouldn’t have co-existed.
The group published their findings in the journal Science Advances as they ran simulations of Earth’s atmosphere during Archean, Proterozoic, and Phanerozoic periods. They found that during the Archean period, Earth’s atmosphere didn’t contain much oxygen with life forms finding it difficult to survive due to the coexistence of methane, carbon dioxide, and nitrogen in the atmosphere. Afterwards during Proterozoic period, Earth saw a growing number of oxygen producing microbes that helped to create life-sustaining atmosphere.
The researchers wrote, “We show that methane mixing ratios greater than 10-3 are potentially biogenic, whereas those exceeding 10-2 are likely biogenic due to the difficulty in maintaining large abiotic methane fluxes to support high methane levels in anoxic atmospheres.”