Japan's KAGRA searches the sky for gravitational waves

The newly operational KAGRA will bump the number of gravitational-wave observatories to four, which will allow scientists to better triangulate the source of ripples in space-time. Deep underground, below a mountain and in a mine in the northern portion of the Gifu Prefecture on Japan's main island, sits an observatory that searches for ripples in space-time. It's called the KAmioka GRAvitational wave detector, or KAGRA. For several weeks earlier this year, it ran for the first time. The next ti...