Insight into planet Earth through satellite photography from space, as well as vantage points from helicopters and cameras on the ground.

Insight into planet Earth through satellite photography from space, as well as vantage points from helicopters and cameras on the ground.

Stephen Hawking challenges volunteers and viewers to consider some of humanity's greatest questions.

Stephen Hawking challenges volunteers and viewers to consider some of humanity's greatest questions.

Using Aviva's invention, the Time Trampoline, the Wild Kratts jump back in time to visit animals that have become extinct.

Using Aviva's invention, the Time Trampoline, the Wild Kratts jump back in time to visit animals that have become extinct.

Co-produced by PBS and BBC, Great Yellowstone Thaw documents how animals in the Yellowstone National Park ecosystem adapt to the changing seasons. Bison, grizzly bears, [More]

Co-produced by PBS and BBC, Great Yellowstone Thaw documents how animals in the Yellowstone National Park ecosystem adapt to the changing seasons. Bison, grizzly bears, wolves, beavers and great grey owls are some of the species that use their innate survival instincts to adapt to the drastic change in temperature -- temperature that can swing as much as 140 degrees over the course of a few months. Dr. Kirk Johnson, the Sant Director of the Smithsonian National Museum of Natural History, hosts the presentation.

The Wild Kratts team ventures into the deep sea aboard Aviva's newly designed Deep Sea Explorer.

The Wild Kratts team ventures into the deep sea aboard Aviva's newly designed Deep Sea Explorer.

The Kratts brothers take their friend Aviva down the Amazon River to help her get inspired for her next invention.

The Kratts brothers take their friend Aviva down the Amazon River to help her get inspired for her next invention.