Saturday, February 20, 2010
I WENT OUT INTO THE NIGHT, I WENT OUT TO FIND SOME LIGHT
Pictures of space via NASA's Astronomy Picture of the Day. The pictures are accompanied by brief explanations written by astronomers. Below is an example of the kind of thing that makes you feel incredibly small and useless. On top of the near-crippling awe that these photos inspire, we are also informed of the existence of a mysterious dark energy. The presence of which only serves to expand and preserve the universe. It's half comforting, half terrifying.
"Explanation: This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for its discoverer, who, 50 years ago, was trying to understand why fluids like mayonnaise move so slowly. Today, evidence is accumulating that most of the energy density in the universe is in an unknown form dubbed dark energy. The form and genesis of dark energy is almost completely unknown, but postulated as related to vacuum fluctuations similar to the Casimir Effect but generated somehow by space itself. This vast and mysterious dark energy appears to gravitationally repel all matter and hence will likely cause the universe to expand forever. "