First, it's important to know that the big bang wasn't an explosion of matter into empty space—it was the rapid expansion of space itself. This means that every single point in the universe appears to be at the center. Think of the universe as an empty balloon with dots on it. Those dots represent clusters of galaxies. As the balloon inflates, every dot moves farther away from every other dot.
Mapping the universe and its billions of galaxies is a tedious business, but a project spanning more than a decade and mashing up near-infrared sky surveys with painstaking redshift analysis has produced the wold’s most detailed 3-D map of the local universe. Reaching out to a distance some 380 million light-years from our own solar system, the 2MASS Redshift Survey (2MRS) was presented today at the 218th meeting of the American Astronomical Society.
After a five-year study of 200,000 galaxies, scientists are more certain than ever that dark energy acts as a repulsive force, tearing the universe apart at an accelerating rate. The research confirms the idea that dark energy dominates gravity throughout the cosmos. But no one has any idea what dark energy actually is or how it works.
Every December since 2004, engineers have flown to the South Pole to drill 8,000-foot-deep holes in the ice. The team lowers cables, each strung with 60 disco-ball-size light sensors, into the holes and let them freeze over. So far they have completed 79 such holes, set in a grid half a mile on each side, and plan to drill the final seven this month. The result will be the IceCube Neutrino Observatory, a cube of ice packed with 5,320 sensors looking for cosmic particles.
The Wilkinson Microwave Anisotropy Probe, or WMAP, has been gathering information about the Big Bang, dark matter, and the nature of the universe for nine years now, and it's finally being put to rest (rest being a "parking orbit" around the sun).