Dark Matter, Dark Energy

Sounds like something from Star Wars, or perhaps Harry Potter. It's actually some theories astrophysicists are throwing around. Apparently, this is the composition of our universe:

5% normal matter, 25% dark matter, 70% dark energy

"Normal matter" consists of things that we can see. All these things give off energy at a certain wavelength of light that may or may not be able to be seen with the naked eye (ie visible light versus UV, infrared, radio waves).

In recent decades, researchers have become more and more convinced that there is a vast amount of material in the universe that does not give off any energy. This mysterious "dark matter" is thought to be common but invisible. Its presence is inferred because "normal matter" cannot account for all the gravity that exists. As in, if there weren't an explanation beyond what we can see, galaxies would fly apart rather than hold together.

If all this weren't mysterious enough, scientists invoke "dark energy," a force that is slight stronger than and goes against gravity, which is responsible for causing the universe to continue to expand slowly.

Interesting stuff. They may be right, they may be wrong - only time will tell. Science makes observations of the world around us, and scientists work to make sense of these observations. Hypotheses and theories of how things work evolve as our understanding of the world changes. Whether there are distinct entities of "dark matter" or "dark energy" is a matter of human interpretation of scientific data. These current theories may hold true for the next several hundred years, or may fall by the wayside, joining ether theory and other theories that have since been disproven. But it doesn't matter. What matters is that the investigative human spirit is a beautiful thing and that our universe --- is truly awe-inspiring.