Mass.) WGBH (Television station : Boston

Stick around with the scientists who remain behind when the Philippines' Mount Pinatubo erupts and see astonishing footage of the world's largest volcanic eruption in 80 years.

On the picturesque bluffs of Martha's Vineyard, disaster looms. The historic Gay Head Lighthouse, weighing more than 400 tons and soaring 175 feet above the sea, is precipitously close to toppling into the ocean. As a team of engineers attempts to move the iconic red brick structure inland to safety, discover the geology they encounter, the archaeology they discover, and technology they employ in this lighthouse rescue.

Alzheimer's disease ravages the minds of over 40 million victims worldwide. The cause of Alzheimer's and whether it can be stopped is one of the greatest medical mysteries of our time. Join courageous patients participating in clinical trials, and then go behind the scenes of the major drug trials to see how researchers target and test therapies that may slow and even prevent Alzheimer's.

Host Neil deGrasse Tyson will tackle one of science's major challenges in each video, framed as a simple question that ordinary people wonder and worry about. Neil will guide us as he explores dramatic discoveries and the frontiers of research that connect each central, provocative mystery. Episode includes: 1) How Smart Are Dogs? - Meet an extraordinary boarder collie and other dogs changing our view of canine intelligence. 2) How Smart Are Dolphins?...

"Twenty-five years ago, NASA launched one of the most ambitious experiments in the history of astronomy: the Hubble Space Telescope. This single telescope has helped astronomers pinpoint the age of the universe, revealed the birthplace of stars, and uncovered black holes lurking at the heart of galaxies. In honor of its anniversary, Nova tells the remarkable story that forever changed our understanding of the cosmos and our place in it." --

Documentary about Theodore Roosevelt. Explores the influence of Rossevelt's childhood, his rise to the U.S. Presidency, and the years after he left office.

Five years after the Fukushima disaster, the future of nuclear power is in question. Join engineers as they embark on an unprecedented cleanup and investigate new nuclear technologies that would prevent future meltdowns.

This inspirational documentary is about a band of courageous civil-rights activists calling themselves the Freedom Riders. Gaining impressive access to influential figures on both sides of the issue, it chronicles a chapter of American history that stands as an astonishing testament to the accomplishment of youth and what can result from the incredible combination of personal conviction and the courage to organize against all odds.

Host Neil deGrasse Tyson will tackle one of science's major challenges in each video, framed as a simple question that ordinary people wonder and worry about. Neil will guide us as he explores dramatic discoveries and the frontiers of research that connect each central, provocative mystery. Episode includes: 1) Space Dangers - Can we protect Mars-bound astronauts from deadly meteroids and the ill effects of radiation and zero gravity? 2) Next-Generation...

On 12/26/04 a series of tidal waves killed thousands and devastated communities around the Indian Ocean. With around 100 tsunamis striking the world's coastlines each decade, Nova investigates what made the recent event so powerful and catastrophic.