Assertion: dark matter | /r/AtLocation | the universe
Facets:
Source sentences:
text: In the 1980s it was proposed that these may be the explanation for the dark matter thought to exist in the universe.
text: However, not everyone is convinced, with some physicists saying that these primordial black holes are unlikely to explain all the dark matter found in the universe.
text: So, it is important to know how much dark matter exists in the universe.