Snack-Sized Science
A New Way to Find Life?
Finding life outside of Earth is one of humanity’s biggest challenges. It could answer a fundamental question — are we alone? — but it’s a difficult problem, since life is complex. What if complexity isn’t a problem, but actually the solution?
Biology is very good at creating complexity, since life has ways of encoding detailed information and running complex chemical reactions. New research published in Nature presents the Molecular Assembly Index (MA), which measures the complexity of molecules. Complicated molecules created by life have a higher MA value than other non-organic materials, like rocks.
The researchers calculate a molecule’s MA based on the minimum number of steps it would take to assemble that molecule from basic building blocks. They measured the MA of many different materials — from beer to bacteria to limestone and beyond — to prove that this method reliably works as an indicator of life (which it does!). This adds to astrobiologists’ ever-growing toolkit for identifying extraterrestrial life.
Many methods for detecting biological life are meant for remote observations, like a telescope peering at a far away exoplanet’s atmosphere to see what it’s made of. Measuring MA, on the other hand, happens in situ with an instrument like a mass spectrometer, so it could someday ride aboard a rover to investigate another planet, like Mars.
Read the original study here: https://www.nature.com/articles/s41467-021-23258-x
