The systems artificial intelligence (AI) are learning to do many tasks that are complex for people. Rare is the week in which we do not know its application or advances in some new field. Well, this Monday, an American team reveals that an AI system is doing quite well – with 90% reliability – in carrying out a key step in the search for life outside Earth: distinguish whether the origin of samples is biological or not (abiotic). Or what is the same, if these samples indicate that there are (or were) living organisms in that place.
Searching for traces of extraterrestrial life, past or present, is the great desire of scientists. This research is carried out within our solar system with robotic missions such as those of the Curiosity or Perseverance vehicles on Mars, and in much more distant worlds (exoplanets or extrasolar planets) through other techniques and telescopes that try to detect those worlds outside. of the Solar System biosignatures or biomarkers, that is, elements that may indicate signs of life, as we know it on Earth.
Among these biosignatures (elements, isotopes, molecules or phenomena that provide evidence that there has been or was life) are molecular oxygen, ozone or methane. But the existence of one of these elements does not necessarily mean that there is life, that is, that it is a biomarker. For example, on Earth methane is produced by living beings such as bacteria or cows. This gas has also been detected on Mars, but the origin could be both volcanism and biological processes.
In the same way, there are organic components that have been produced by biological activity (by living beings) or non-biological, and it is there, in the distinction between the two, where the artificial intelligence system that this Monday presents in the magazine is being trained. Proceedings of the National Academy of Sciences (PNAS) a team led by Jim Cleaves and Robert Hazen, from the Carnegie Institution for Science, in the USA.
As astrobiologist and mineralogy specialist Robert Hazen explains, they started from “the idea that the chemistry of life differs fundamentally from that of the inanimate world, that there are ‘chemical rules of life’ that influence the diversity and distribution of biomolecules. If we could deduce those rules, we could use them to guide our efforts to model the origins of life or to detect subtle signs of life on other worlds.”