Virtually no one thinks that we are alone in the galaxy anymore. However, as data collected by NASA’s Kepler satellite indicates, it appears that there are many more planets than we can think of with life far from the Solar System. According to these data, one in five stars similar to our Sun would have a planet similar in size to Earth in a habitable zone.
Of the approximately 100 billion stars found in our galaxy, how many can a planet within the habitable zone have orbiting around it? This is the question that researchers from the University of California at Berkeley and the University of Hawaii have asked themselves. And it is that for there to be life (as we know it) it is necessary that it have water, as on Earth, that is to say at a distance neither too far nor very close to its star. If it is too far it will be too cold, while if it is too close it will be too hot a planet.
Researchers have analyzed thousands of data collected by the Kepler and Keck space telescopes in Hawaii. Their conclusion: About 22 percent of Sun-like stars (at the temperature level) have planes of similar size to Earth (between one and two times its size) and orbit around them at a distance within the habitable zone.
As Erik Petigura, director of the study published in PNAS explains, “this means that when you look up at the thousands of stars in the night sky, the closest Sun-like star with an Earth-sized planet located in the habitable zone is probably only 12 light years away and can be seen with the naked eye. “
However, the fact that these conditions exist is not a safe value for liquid water and life to exist on other planets.
