The news: A new analysis of data collected by NASA’s Kepler space telescope has predicted that there are at least 300 million potentially habitable planets orbiting stars like the sun, and likely way more—possibly over 3 billion. Given that the best opportunity for finding extraterrestrial life resides in locating planets that resemble Earth, it’s a tantalizing finding.
How they reached that figure: Scientists have made several attempts in the past to use Kepler data to work out how many sun-like stars in the galaxy have potentially habitable exoplanets in their orbit. But the answers have had extremely wide ranges. Two major issues have created this large window: incomplete data, and the need to cull false detections from the Kepler data set. The new study addresses both of these problems, by also using stellar data from Gaia, the European Space Agency’s mission to map every star in the Milky Way, and spending years analyzing the Kepler catalogue to strip away obscuring elements and ensure that only real exoplanets are left.
However: The study has yet to be peer-reviewed, and although its uncertainties are smaller than those in previous efforts, they are still quite large. Read the full story.