What might look like a tear in the fabric of reality (the Pandorica opens), is actually a dark molecular cloud. A dark molecular cloud is a patch of space with a high concentration of dust, and molecular gas which absorbs practically all visible light. You can however see right through the cloud when observing it at the infrared energy band.
We don’t know how they form but it is thought that they are breeding grounds for new stars, and it has also been found that Barnard 68 is likely to collapse and form a new star system. (x)