Frontiers of Deep SpaceExplore the revolution in our understanding of the nature of the universe and how it came to be.

Scientists have further narrowed the search for a hypothetical particle that could be dark matter, the mysterious stuff that makes up 80 percent of all the mass in the universe. The video from NASA Astrophysics presents the new results, compiled from two years' worth of data from NASA's Fermi Gamma-ray Space Telescope.

Although no one is sure what dark matter is, one of the leading candidates is a yet-to-be-discovered particle called a weakly interacting massive particle (WIMP). When two of these WIMPs meet, the theory goes, they can annihilate one another and generate gamma rays.

From EsoCast, Dr. J. explores the upheaval in our understanding of the universe brought on by the discovery that the universe is not just expanding, but is accelerating outward at an ever increasing pace.

Was Einstein wrong? Are we missing something crucial in our understanding of how it all began? Either way, this is one of the most exciting scientific discoveries in a long time.

Watch the full documentary now (playlist - 3 hours, 37 minutes)