Scientists have found a promising new clue in the hunt for alien life.
Scientists have a new theory about the chances of finding aliens
Experts from the University of Birmingham and the Massachusetts Institute of Technology (MIT) have theorised that far-off planets with low levels of carbon dioxide could be inhabited by other life forms.
The scientists think that NASA's James Webb Telescope is the ideal tool to search for depleted levels as it has previously uncovered atmospheric conditions of exoplanets.
Julien de Wit, assistant professor of planetary sciences at MIT, said: "The Holy Grail in exoplanet science is to look for habitable worlds and the presence of life, but all the features that have been talked about so far have been beyond the reach of the newest observatories.
"Now we have a way to find out if there's liquid water on another planet.
"And it's something we can get to in the next few years."