Is there anyone out there? Astronomers have been pointing their radio telescopes at the skies for decades trying to pick up alien signals, so far without success. But now there's a new way of looking for aliens. Hitch a ride with Dr Graham Philips as he joins astronomers trawling through the galaxy looking for signs of extra-terrestrial intelligence.

NASA may have just gotten one step closer to the answering the question: are we alone? The Spitzer Telescope has made a groundbreaking discovery of exoplanets that could be similar to our own. And as Kepler also continues its search, our understanding of the universe continues to be redefined.

For decades some have suspected that there might be others out there, intelligent beings capable of communicating with us, even visiting our world. It might sound like science fiction, but today scientists from across the globe are scouring the universe for signals from extraterrestrials. Horizon obtained exclusive access to film researchers at the Green Bank Telescope searching for radio signals from Tabby's Star, a star so mysterious that some scientists believe it might be surrounded by a Dyson Sphere, a vast energy collector built by advanced aliens.

In August 1977, the Big Ear Radio-telescope in Ohio received a strange signal from the Sagittarius constellation while searching for intelligent extra-terrestrial life. It had a duration of 72 seconds and an intensity 30 times higher than usual. Named the Wow signal, it is still being considered as one of the best examples of having being sent by intelligent extraterrestrial life. But, nothing has revolutionised the search of extra-terrestrial intelligent life as much as the recent discovery by the Kepler Satellite, of thousands of Earth-like planets where life could be possible. Join the debate with this stunning documentary, as we ask Is Anybody Out There?

An informative and ambitious journey exploring how the evolution of scientific understanding is intimately interwoven with society's historical path. The Story Of Science tells the forces that came together to create scientific knowledge; the practical business of making instruments and machines; the great forces of history – revolutions, voyages of discovery and artistic movements – and the dogged determination of scientists and experimenters. This is the story of how scientific ideas shaped the modern world and how science made history. Michael Mosley begins the first episode with the story of one of the great upheavals in human history - how we came to understand that our planet was not at the centre of everything in the cosmos, but just one of billions of bodies in a vast and expanding universe. He reveals the critical role of medieval astrologers in changing our view of the heavens, and the surprising connections to the upheavals of the Renaissance, the growth of coffee shops and Californian oil and railway barons. Michael shows how important the practical skills of craftsmen have been to this story and finds out how Galileo made his telescope to peer at the heavens and by doing so helped change our view of the universe forever.

20 years ago, two astronomers made a remarkable discovery, one which would change the way we view the universe for ever. A planet outside our solar system, orbiting a distant star - an exoplanet. Since then, we have found worlds where it rains diamonds, ones that boil at 3,000 degrees centigrade and even a world with four suns in its sky. But the big question is - will we ever find another Earth? As we close in on the discovery of the 2,000th planet outside our solar system, or exoplanet, we investigates the techniques that are revealing so much about these alien worlds. The documentary asks if we are really any closer to finding another world like our own - a second Earth.