From a palace in Ferrara, Italy, cosmologists have unveiled the most detailed maps yet of the infant universe. The announcement, on December 1, kicked off a weeklong conference showcasing the latest findings from the European Space Agency’s Planck satellite. The new results largely confirm earlier measurements of the makeup of the cosmos, but they also rule out some ideas about dark matter, the elusive substance thought to bind galaxies together.
There are no major surprises, says David Spergel, a cosmologist at Princeton University who, like most researchers, is relying on e-mail and Twitter to hear about the results. Compared with Planck’s first results, presented in 2013, not much has changed (SN: 4/20/13, p. 5). We live in a 13.8 billion-year-old universe where atoms and their subatomic components account for only 4.9 percent of all the mass and energy that’s out there. Dark matter makes up 26.6 percent, and 68.5 percent resides in the even more enigmatic dark energy, a repulsive force that is speeding up the expansion of the cosmos.