Astronomers have discovered a ‘treasure trove’ of rare dwarf satellite galaxies orbiting our own Milky Way. The discoveries could hold the key to understanding dark matter, the mysterious substance which holds our galaxy together.

Earlier surveys of the southern sky found very little, so we were not expecting to stumble on such treasure
Vasily Belokurov
A team of astronomers from the University of Cambridge have identified nine new dwarf satellites orbiting the Milky Way, the largest number ever discovered at once. Thefindings, from newly-released imaging data taken from the Dark Energy Survey, may help unravel the mysteries behind dark matter, the invisible substance holding galaxies together./.../