NASA’s Kepler mission is over, but the data that it collected is still being studied by astronomers all over the world. During its search for planets amongst billions of stars in our galaxy, just how many are possibly habitable? According to astronomers, the answer is much more than we think. Astronomers at UC Berkeley and the University of Hawaii now believe that the odds of a star having a potentially habitable planet is one out of every five.
We define habitable planets by their size. Potentially habitable planets are generally around the same size as Earth and show characteristics of a surface temperature that could sustain life. With the information collected by Kepler, astronomers now think that tens of billions of planets possibly fall into that category. This means that if you look up at the stars each night, one of those stars you see with your naked eye might contain a habitable planet. In other words, finding Earth-like planets isn’t as rare as one might think. In fact, planets like ours might be common, at least in the Milky Way galaxy.
Of course, before we get too excited, there is always a big “but.” Just because a planet is Earth-sized doesn’t necessarily make it habitable, even if the temperature of the planet might make it seem so. Some of these planets could have hot atmospheres that wouldn’t allow for life to survive. Others could have atmospheres that are too cold. At this point, we just don’t know enough about the variety of planet types out there.
However, this research team is going further with analyzing Kepler’s data. They used a series of algorithms and tests to determine which planets exist in habitable zones, including some that might were missed by other astronomers looking at the same data. They even introduced fake planets to test their software. Their findings determined that at least 22 percent of stars similar to our sun could have planets capable of supporting life.
Kepler went to space to ask the question: How many stars in the night sky have potentially habitable planets? Now, we’re finally seeing answers: more than we ever thought.