Scientists Propose a Radical New Method To Find Alien Life

Researchers propose Assembly Theory, which measures chemical complexity instead of specific biosignature gases.

The method assigns an assembly index that counts minimum steps needed to build molecules and flags unlikely-to-form compounds.

Earth's atmosphere rates higher in molecular diversity by this measure compared with Venus, Mars and exoplanet archetypes.

Assembly values can be derived from infrared spectroscopy and are intended for use with NASA's Habitable Worlds Observatory.