astrobiologists

We are very used to hearing that someone has found possible signs of life in space. Then life is never found, but the trail seems to be there. All of these findings often end up being false positives, something astrobiologists are more than familiar with. However, According to a study just published in Nature Astronomy, They could be overlooking false negatives and that would be serious. Pass life long. What the authors of this study point out is that false negatives could be more common than we think. That is to say, many of the times when it is clearly concluded that there is no life in a place in space, it could be that it did exist, but it had been passed by without being detected. The causes. There could be three reasons why these false negatives occur. On the one hand, no traces of life are preserved. That is, it exists or has existed, but has not left a detectable trace. It could also be that this fingerprint is difficult to detect. Or, perhaps, that the methods used to detect it have limitations. Along these lines, the authors of the study give an example. Let’s imagine that there is a living being that, through its metabolic reactions, generates some gas that is understood as a trace of life. Maybe oxygen or methane. But let’s also imagine that there is a geological activity in that place that captures that gas from the environment. I wouldn’t have time to measure it. Therefore, the detection of life would have to be covered from other points. The risks. There are two main risks of not paying attention to false negatives. On the one hand, instruments that would help find even more traces of life would be deprioritized. If we do not find anything that justifies its development, we limit the possibilities of continuing searching. On the other hand, if life is not adequately searched for, resources from other planets where such life is found could be exploited. We would destroy it before we even knew it existed. Solutions. These scientists believe that searching for patterns using artificial intelligence could be an option. If the usual methods have not worked so far, perhaps we should ask an algorithm to detect patterns that have gone unnoticed to find new search paths. Along the same lines, it would also be necessary to study the terrain better and pay attention to anomalies. For example, if an unconventional type of oxidation is detected on a planet, inexplicable with what we know on Earth, it could be that it was associated with some form of life. It may not look like the oxidation carried out by terrestrial living beings, but who says it has to be the same? You have to think outside the box. Combine different types of work. In short, these scientists consider that to adequately search for life it is necessary to combine laboratory experiments with modeling and field work. But, above all, it is important to change the questions we ask ourselves. What if it has already been found? In 2019, a former NASA scientist told in an article for Scientific American that, according to himhis agency found life on Mars, but accidentally destroyed it. Supposedly, it all happened in the 1970s, in an experiment that was part of the Viking mission. This consisted of depositing nutrients in the soil and checking if gases typical of microbial decomposition were produced. Then, to ensure that it was not a coincidence, they would repeat the process, but adding a substance lethal to living organisms to the soil. In that case, gases should not be produced. And no, they were not produced, so there was something alive generating the gases. It was great news, but NASA did not publish that result, because when trying to replicate the experiment it came back negative. In science it is very important to replicate the results, so they concluded that it must have been a false positive. However, this former member of NASA, Gilbert V. Levin, believes that they destroyed life unintentionally and that is why they could not replicate it. This is no longer an anecdote. Most likely, they would not have found life. However, this story shows that we are always more predisposed to false positive than false negative. The focus would have to be changed a little. Maybe then we will finally find some life beyond our own planet. Images | Eric Erbe and Christopher Pooley (illustrative image of E.coliit has nothing to do with the study)/ Brett Ritchie (Unsplash) In Xataka | Life on Earth underwent a spectacular change 540 million years ago. We have a new explanation why