Universal heart of darkness
Physicists currently estimate that only 4% of the universe is made up of baryonic matter, which we can detect and measure with our current senses and instruments. So, 96% of what makes up the universe is in a form that has never been observed directly in a laboratory: 73%t is believed to be dark energy and 23% dark matter. Dark matter cannot be seen because it emits no light. It was hypothesized 50 years ago to explain why the outer limits of a galaxy travel at the same speed as the dense center. With so much of the ‘verse still invisible to us, a unified Theory of Everything may be further away than we’d hoped.
The darkness inside of everything, TheAge.com.au