video recordings for people with visual disabilities

Discusses attempts by scientists to explain the dramatic weakening of Earth's magnetic field and contemplates what might happen to the planet if the magnetic field were to vanish.

The source of the earth's great variety of animals was a scientific mystery until Charles Darwin proposed the idea of natural selection. Nova presents breakthroughs in a new science nicknamed "evo devo" that are linking the enigma of origins to another of nature's mysteries, the development of embryos.

A look at the life and career of Depression era heavyweight boxer James Braddock, and his experiences as a fighter and a longshoreman, and his bout with champion boxer Max Baer.