Before Present (BP) years is a time scale used mainly in geology and other scientific disciplines to specify when events in the past occurred.his usage differs with the recommendation by van der Plicht & Hogg, followed by the Quaternary Science Reviews, both of which requested that publications should use the unit  a  [for year] and reserve the term BP for radiocarbon estimations.
The standard model of cosmology indicates that the total massâenergy of the universe contains 4.9% ordinary matter, 26.8% dark matter and 68.3% dark energy. Thus, dark matter constitutes 84.5% of total mass, while dark energy plus dark matter constitute 95.1% of total massâenergy content.
The void is an illusion. The universe is certainly not empty, that's a fact, but its not very dense either. Today, the visible universe consists mostly of empty space, void, while ordinary matter accounts for only 4 percent of the total mass. So where is the rest of 95 percent of the universe's mass? In dark energy and dark matter, according to some physical theories. Further still, the void doesn't seem to be so empty after all, but filled with an ocean of elementary sub-atomic and weakly interacting particles.