https://phys.org/news/2018-06-greenland-telescope.html

It is located on the northwest coast at the US Thule airbase, and is part of an ambitious project, the Event Horizon Telescope (EHT), to study black holes.

Black holes are areas of space where the concentration of matter is so high that gravity is incredibly strong. So strong, in fact, that no light can escape when it ventures too close.