Scientists have created a computer model of Earth that has never had life on it, allowing them to track how the atmosphere and other planetary layers would change under the influence of geological processes. This new development will help astronomers clearly distinguish inhabited worlds from planets where life might actually exist, as well as correctly interpret signals coming from the distant universe.
Researchers at the University of Washington modeled the planet's evolution over a span of five billion years, from its formation into the future. During testing, the model accurately reproduced 19 planetary characteristics, and it can now be adapted for the study of other rocky planets outside the Solar System.
On Earth, living organisms continuously emit oxygen and methane, which enter into chemical reactions, so their simultaneous presence in the atmosphere often indicates the continuous replenishment of supplies. However, to reliably interpret such signals, it is necessary to compare observations with models of planets that lack life.
The authors also expect that this model will help effectively develop future telescopes specifically designed to search for possible signs of life on exoplanets.
This modeling fundamentally changes the approach to how scientists test the habitability potential of distant space bodies. When suspicious gases or chemical compounds are detected during observations, the primary challenge becomes determining whether their origin is natural or biological. As the capabilities of telescopes grow year by year, the availability of such comparative tools will help avoid premature conclusions and make the search for life in the universe more well-founded.
