In 1996, near Kennewick, Washington, a suspected murder victim is identified by forensic anthropologists as Caucasian - but turns out to be almost 10,000 years old. For fifty years our picture of prehistoric America has rested on the premise that the earliest inhabitants of the Americas were east Asians of mongoloid stock, the ancestors of today's Native Americans. But the discovery of the Kennewick Man, along with several other startling finds in recent years, has thrown that once widely accepted idea into question and revolutionized the science of paleo-anthropology. It has also embroiled scientists in a bitter conflict with Native American groups who want the scientific study of early Americans halted. Who and what do Kennewick Man and others represent? NOVA is following the efforts of paleo-anthropologists work to decode the story in the bones of people who died 10,000 years ago.

The film probes the enigma of our Neanderthal cousins and the roots of our own ancestry.

Go inside NASA's risky field trip to the red planet in this tense and dramatic behind-the-scenes chronicle of the $820 million Mars Exploration Rover (MER) project.

NOVA follows a team of scientists as the monitor the Martian rovers Spirit and Opportunity. Spirit runs into some problems, but Opportunity takes a photograph that may confirm the existence of water on Mars.

A look at the 2002 discovery of a four-winged crow-sized dinosaur fossil dubbed Microraptor, which has rekindled the scientific debate over the origins of flight. Included is a wind tunnel test of a "flight-ready" model of the 130 million-year-old Microraptor.