Voyager has had a profound effect on our knowledge of the cosmos. Its mission was supposed to last five years but remains ongoing, fundamentally changing our understanding of the solar system. Featuring contributions from key scientists, we’ll explore what’s been achieved and what happens next.
2016 • Astronomy
Scientists are only now starting to unravel the secrets of comets. Often referred to as dirty snowballs, they contain ice and elements from the very start of the universe. Some theorize that a comet, crashing into our planet, brought with it the organic material that started life on Earth. Spacecraft continues to offer new information on their makeup, from bringing back samples from a comet's tail to direct contact when a NASA-launched craft slammed into the comet Tempel-1.
Sagan discusses comets and asteroids as planetary impactors, giving recent examples of the Tunguska event and a lunar impact described by Canterbury monks in 1178. It moves to a description of the environment of Venus, from the previous fantastic theories of people such as Immanuel Velikovsky to the information gained by the Venera landers and its implications for Earth's greenhouse effect. The Cosmos Update highlights the connection to global warming.
Almost everything we know today about the beautiful giant ringed planet comes from Cassini, the NASA mission that launched in 1997 and arrived at Saturn in 2004. Since then, the space probe has been beaming home miraculous images and scientific data, revealing countless wonders about the planet, its rings and 62 moons - including some that could harbor life. As the mission approaches its final days in 2017, it attempts one last set of daring maneuvers - diving between the innermost ring and the top of Saturn's atmosphere. Aiming to skim less than 2000 miles above the cloud tops, no spacecraft has ever gone so close to Saturn, and hopes are high for incredible observations that could solve major mysteries about the planet's core. But such a daring maneuver comes with many risks and is no slam dunk. In fact, slamming into rocks in the rings is a real possibility. Join NASA engineers for the tense and triumphant moments as they find out if their bold re-programming has worked, and discover the wonders that Cassini has revealed over the years.
Scientists using the Hubble Telescope study vivid images from 12 billion and more light years away and observe that many galaxies cluster together like -- soap bubbles! Analyzing factors like dark matter and gravitational lensing, how can astronomers confirm this amazing bubble structure?
Harvard professor and best-selling author, Dr. Lisa Randall, simplifies and expounds upon some of modern physics' most basic questions. What is dark matter and dark energy? What is the fundamental nature of space and time? What do we not know yet about the universe and its fundamental properties?