A Year on Planet Earth

Stephen Fry hosts a new landmark wildlife series exploring how our annual journey around the sun impacts nearly all life on Earth. As we orbit our star, it is on a tilted axis of around 23.5 degrees and this creates the seasons. For those in the northern hemisphere, Winter brings plummeting temperatures, darkening days and times of hunger. On Svalbard's frozen sea-ice, a polar bear mother is preparing her cub for a life alone. Each week without food, she loses around a tenth of her body weight.

On the other side of the planet the far south leans towards the sun, bringing warmth and light.

It is the southern summer. Deep in the Southern ocean, King Penguins flock to Marion Island, a tiny spec of land between South Africa and Antarctica. It is breeding season at this time of year and it becomes home to a million penguins. In the tropics the intensity of the sun drives cloud formation, bringing the rains. For a baby African elephant, this is the season of play but tougher times lie ahead.