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.
We believe most of the dark matter is composed of new particles smaller than atoms that are different from anything scientists have ever detected and studied. It seems that the very essence of most of the matter in the universe is different from what you and I and rocks and trees and Earth and the Sun are made of. Trying to understand dark matter is one of my favorite topics in science, so I'm glad I had the chance to shed some light on it for you.