Grand Design

S1 E5: The forces of nature, operating at large and small scales create a universe of symmetry and form. Now we consider the interplay of those forces in creating structures as dramatic as Saturn’s rings and the Whirlpool Galaxy, a classic example of a grand design spiral. Stretching the Canvas – The matter we see, both the bright stars and gas and the dark dust, is really just the tip of the iceberg. By watching how galaxies rotate, astronomers realized there must be something else there that is invisible but exerts a powerful gravitational pull. This is dark matter. It has an amazing influence on the universe, forming a “gravitational lens” which distorts our view of distant stars, but also keeping gravity from pulling the universe in on itself. The Hubble Space Telescope not only has allowed us to learn more about dark matter, but about dark energy, the mysterious force that is causing the universe to accelerate outwards. That discovery helped resolve one of science’s great mysteries, the age of the universe.