But recently astronomers have used data collected by the European Space Agency’s Gaia spacecraft to detect three previously unknown black holes and, it turns out, are the closest known to Earth.

“Gaia was designed to withstand failures such as radiation storms, micrometeorite impacts or a loss of communication with Earth. It has multiple redundant systems that ensured it could always ...

Europe's Gaia space telescope was powered down and sent into "retirement" on Thursday after a decade revealing the secrets of the Milky Way, but its observations will fuel discoveries for decades ...