Astronomers using the NASA/ESA Hubble Space Telescope have for the first time precisely measured the distance to one of the oldest objects in the Universe — a globular cluster called NGC 6397, one of the closest such clusters to Earth. The new measurement sets NGC 6397’s distance at 7,800 light-years away, with just a 3% margin of error, and even provides an independent estimate for the age of the Universe. This image shows the nearby globular...
