Visiting a hidden location buried beneath the hills of Scotland, Helen experiences some of the most extreme acoustics in the world. Here she learns just how much information can be carried by sound. She discovers how sound has driven the evolution of truly incredible biological systems and complex relationships between creatures that exploit sound for hunting - and escaping from predators. Helen demonstrates how sound waves diffract (bend around objects) and in doing so help us sense danger and locate it. Helen explains how we are not limited to passively detecting sound waves; we can also use them to actively probe the world.
Nuclear energy might have a lot of unused potential. Not only is it one of the best mid term solutions for global warming bit despite what gut feeling tells us, it has saved millions of lives. By investing more into better technologies we might be able to make nuclear energy finally save and clean forever.
Nuclear Energy is a controversial subject. The pro- and anti-nuclear lobbies fight furiously, and it's difficult to decide who is right. So we're trying to clear up the issue - in this video we discuss how we got to where we are today, as the basis for discussion.
Horizon looks at dark energy - the mysterious force that is unexpectedly causing the universe's expansion to speed up. The effects of dark energy were discovered in 1998 but physicists still don't know what it is. Worse, its very existence calls into question Albert Einstein's general theory of relativity - the cornerstone of modern physics. The hunt for the identity of dark energy is on. Experiments on earth and in space generate data that might provide a clue, but there are also hopes that another Einstein might emerge - someone who can write a new theory explaining the mystery of the dark energy.