Till today we have no evidence of extraterrestrial life, but that doesn’t mean it doesn’t exist. Given the size of the universe (there are at least 100 billion stars in our galaxy alone and perhaps 100 billion galaxies of more or less the same size) few scientists believe that Earth is the only one to host life. Let’s take stock of the situation with NASA expert Lindsay Hays.
Read also: Brown dwarfs die alone
What do astrobiologists think?
Until recently, the field of astrobiology was quite disappointing. In the 1960s and 1970s, robot planetary explorers found no traces of life or sustainable environments in the solar system, and the Mars Viking Lander of 1976 failed to detect any biological activity on Mars.
However, the outlook has improved significantly since then. Recent discoveries have raised the possibility of life elsewhere in the solar system and beyond. Astronomical observations have revealed planets around more than 60 nearby stars, while the Galileo probe has detected a possible ocean beneath the surface of Europa, a moon of Jupiter.
But the most significant discoveries were made on Earth itself. Extremophiles, organisms that thrive in extreme environments, have shown that life can adapt to incredibly hostile conditions. Such organisms suggest that life does not require traditional conditions such as sunlight or organic molecules.
Featured Image: Artist’s impression of astronauts on Mars during a dust storm. Credit: NASA/Paul DiMare.
Sources: NASA, ESA.
If you appreciate our scientific dissemination project, you could also consider taking part in it by subscribing to Passione Astronomia. We promise that with your help there will be more and more content to explore and understand the universe.
