At first glance there is nothing special about Kepler-62, just one star against a backdrop of the Milky Way’s 300 billion others. But to astronomers, its flickering light has revealed it as the host star to five orbiting planets, including the most Earth-like world discovered beyond our solar system.
Crucially, two of the planets are in the “habitable zone”, at just the right distance from the star to be neither too cold nor too hot for liquid water to exist on their surface. The observations, which suggest that the necessary conditions for life exist around other suns, have been hailed as a milestone in the discovery of extra-solar planets.
Eric Agol, the University of Washington astronomer who identified the star’s outermost planet, Kepler-62f, which is