In wide-ranging conversations, thirteen celebrated literary figures from six nations discuss their work, politics, morals, and the future of American society.

The history and construction of the iconic Florence Cathedral.

J. Robert Oppenheimer's life and legacy are inextricably linked to America's most famous top-secret initiative - the Manhattan Project. This biography presents a complex and revealing portrait of one of America's most influential scientists.

Using forensic tools, art experts try to determine whether or not a portrait of a young woman in Renaissance dress sold at auction in 2007 is an undiscovered masterwork by Leonardo da Vinci.

Chronicles the history of the African American church from its roots in slavery to the present day.

Now, with the help of new spacecraft and Earth-based telescopes, scientists are seeing the Sun as they never have before and even re-creating what happens at the very center of the Sun. Their work will help us understand aspects of the sun that have puzzled scientists for decades. Secrets of the Sun reveals a bright new dawn in our understanding of our nearest star, one that might help keep our planet from going dark.

Carved from a hundred million pounds of stone, soaring effortlessly atop a spiderweb of masonry, Gothic cathedrals are marvels of human achievement and artistry. But how did medieval builders reach such spectacular heights? Consuming the labor of entire towns, sometimes taking a hundred years to build, these architectural marvels were crafted from just hand tools and stone. Many now teeter on the brink of catastrophic collapse.

Follows the footsteps of the Prophet Muhammad.

Examines the architecture of Gothic cathedrals and how medieval builders were able to construct them with just hand tools and stone.

Presents adventures and learning experiences for children at three zoos in the United States.