New 'exomoon' detection challenges cosmic labels | ESO News

Using ESO's Very Large Telescope (VLT), astronomers have found an object in another planetary system that challenges astronomical labels. The object resembles a moon in that it orbits another object which in turn orbits a star. But the newly found ‘moon’ is itself as massive as a planet, and the object it orbits is neither a planet nor a star. This video summarises the discovery.