University of Washington researchers built a computer model of Earth without life that covers five billion years and can help astronomers assess whether distant planets’ atmospheres point to life or can be explained by geology alone.
The simulation tracks chemical exchanges among Earth’s core, mantle, crust, surface and atmosphere from the planet’s formation about 4.5 billion years ago to roughly 500 million years in the future. The team left biology out to create a starting point for interpreting atmospheric observations. A planet may be able to support life without actually having life.
The model matched 19 measured features of preindustrial Earth, including heat flow through the mantle, within estimated uncertainties. The researchers also generated a spectrum of reflected light that could help guide observations by future telescopes, including the proposed Habitable Worlds Observatory. The work does not identify life on any exoplanet.
Instead, it may help astronomers assess whether a planet’s atmospheric signals could exist without life. The study was published in The Planetary Science Journal on September 18. UW announced the research on November 2.