Astronomers have catalogued more than 6,000 planets beyond our solar system. None has settled the question that matters: is anyone home?
The simulation was released on 18 September 2026 in The Planetary Science Journal by a University of Washington research group led by Samantha Gilbert-Janizek. Gilbert-Janizek is now based at UC Riverside. Earlier models created by the same lab under Rory Barnes from the University of Washington considered the core, mantle, and crust.
She ran the simulation from the formation of the planet about 4.5 billion years ago until almost half a billion years in the future without any life. This simulation can accurately simulate 19 observational properties of the preindustrial Earth. Thus, this world without life still possesses oceans and atmosphere.
Some gases come from living things. Others can come from geology too, so spotting one in a distant atmosphere proves little by itself.
The solution is right here on Earth. Plants and animals release both oxygen and methane, gases which react to annihilate each other. Both of them at the same time would point to an alien astronomer to the presence of living organisms on that world, replenishing their numbers.
The model itself can be used like a plug-and-play system. The parameters of a planet are put in; the model produces the outcome, which should be compared to the observations. These observations could be made by the James Webb Space Telescope, future 30-meter-class ground-based telescopes and NASA’s own Habitable Worlds Observatory.
In case when the planet without any life fits the observations, then no life exists on that world as we know it. In case it does not fit – the planet gains more interest.
Barnes says the model’s calibration against Earth gives the team confidence in future exoplanet simulations. NASA funded the work.
