As new and more powerful telescopes blink on in the next few years, astronomers will be able to aim the megascopes at nearby exoplanets, peering into their atmospheres to decipher their composition and to seek signs of extraterrestrial life. But imagine if, in our search, we did encounter alien organisms but failed to recognize them as actual life.
Source:
https://phys.org/news/2020-05-life-survive-hydrogen-world.html