The journey to Mars to search for evidence of past water.

Rare lemurs and crocodiles with bizarre cave-dwelling behavior draw scientists to remote corner of Madagascar.

NOVA goes beyond the wagging tails and floppy ears to reveal surprising insights into the origin and evolutionary strategy of our canine companions. From a wolf research facility in rural Indiana to New York’s Westminster Dog Show, you’ll discover some amazing dog facts. Did you know the Saluki can beat any other mammal on earth in a three-mile race? That dogs developed spots for a specific reason? And that their evolution is helping us learn about our own?

A team of "glacionauts" verntures into a labyrinth of unexplored and hazardous glacier caves on France's Mt. Blanc.

One of the most exhaustive investigations in aviation history reveals telling clues to the cause of a dissaster off Nova Scotia.

An American mobile hospital mobilized in Iraq faces a daily drama of war-time treatment.

Scientists, meteorologists and storm chasers try to uncover the secrets of F5 tornadoes, the largest, most powerful and most dangerous on Earth. Included are looks at how funnels form and the devastating 2003 tornado in Moore, Oklahoma, plus "tornado tourists," who pay companies to take them to the ferocious phenomena to see them first-hand.

Nova investigates the impact of forces that are radically changing populations in both rich and poor nations.

Can the US military's high tech weaponry prevail against insurgants.

NOVA traces Earth's geologic evolution. The program chronicles the formation of Earth from solar system dust particles that coalesced and became one of the four rocky planets closest to the sun.

NOVA chronicles the discoveries that led to scientists' current understanding of how the universe was formed. The program describes the serendipitous discovery of the Cosmic Microwave Background (CMB) radiation, a faint energy signal believed to be left over from the big bang.

NOVA explores the search for extraterrestrial life. The program describes the Search for Extraterrestrial Intelligence (SETI), a program that scans star systems for radio transmissions from advanced extraterrestrial civilizations and introduces the Drake equation, created by SETI founder Frank Drake, which attempts to quantify the probability of intelligent life in the Milky Way galaxy.

NOVA reports on the different ways scientists explain how life emerged on Earth. The program relates the discovery of extremophiles—bacteria that thrive in harsh subterranean and deep ocean environments similar to those believed to have existed on primitive Earth and describes an attempt to determine when life began on Earth by searching rock formations in Greenland for higher-than-expected ratios of carbon 12 to carbon 13 (in ratios currently only known to be created by life processes).

Examine the complex case of Typhoid Mary, a cook that was quaratined for life against her will in the early 1900s.

Who were the first Ameicans and where did they come from?

Archeologists excavate Stalag Luft 3, the site of the greatest WWII prisoner escape. Prisoners of the camp are also interviewed.

Isreal's remote Cave of Letters holds clues to a Jewish uprising against the Romans.