One out of every five Sun-like stars in our galaxy has an Earth-like planet in orbit, according to an exciting new analysis of data collected from NASA's Kepler telescope. The Kepler, which recently ended its mission to find Earth-like planets, provided years' worth of data for scientists to dive into in the search for other worlds with conditions amenable to hosting life. The latest study out of that trove is evidence that we're far from hearing the end of Kepler's work.
The analysis is actually an educated estimation based on data collected from one small sample of our galaxy, using Kepler's technique for detecting planets around other stars. Looking at a planet at the proper angle, the telescope could detect slight dips in light from far away stars. Those dips, reliably, represent a planet orbiting between the sun and the device, blocking some of the light. And the amount of light it blocks indicates the size of the planet. That's how Kepler identified over 3,500 potentially Earth-like planets over its tenure. For the most recent study, a team of researchers concentrated on data from 42,000 Sun-like stars. 603 of those stars contained candidate planets in orbit, only 10 of which turned out to be Earth-like, defined here as having a similar size and distance of orbit to Earth's.