Season 49

Discover how NASA engineers built and launched the most ambitious telescope of all time.
Ultimate Space Telescope

Ancient footprints provide new evidence of humans and extinct giant beasts of the Ice Age.
Ice Age Footprints

Dinosaur Apocalypse: The Last Day
Scientists use new fossils to reconstruct the day the dinosaurs died.
Dinosaur Apocalypse: The Last Day

Dinosaur Apocalypse: The New Evidence
Striking new fossils paint a picture of life right before the asteroid impact.
Dinosaur Apocalypse: The New Evidence

Determined: Fighting Alzheimer's
Follow three women enrolled in a new study to try to prevent Alzheimer’s.
Determined: Fighting Alzheimer's

Sir David Attenborough explores a site with traces of ancient mammoths and Neanderthals.
Great Mammoth Mystery

In the Arctic, enormous releases of methane, a potent greenhouse gas, threaten the climate