We are the generation of human beings that are going to know whether or not we're alone in the universe. This episode explores the search of exoplanets, from ancient Greek philosophers to the discoveries made possible with the Kepler Telescope. Unbelievable new worlds, planets made of diamond, planets of raining glass, worlds in collision, some plunging into stars, and others that just might harbor life.
Thanks to today's planet hunters, our views of the universe and of our place in it are undergoing one of the greatest revolutions in scientific history.

Humans have long gazed up at the night sky, wondering whether other lifeforms and intelligences could be thriving on worlds far beyond our own. But over the last few decades, ultra-sensitive telescopes and dogged detective work have transformed alien planet-hunting from science fiction into hard fact. We expected to find worlds similar to the planets in our own solar system, but we instead discovered a riot of exotic worlds. Vivid animation based on data from the most successful planet hunter of them all, the Kepler space telescope, brings these worlds into view: puffy planets with the density of polystyrene, unstable worlds orbiting two suns and 1,000-degree, broiling gas giants with skies whipped into titanic winds.
But perhaps the most startling discovery was the number of worlds that may be contenders for a second Earth, at the right distance from their sun to have that ingredient so crucial for life as we know it, liquid water. Amongst them, we witness the most tantalizing discovery of all: a so-called ‘super-Earth’, situated in the Goldilocks zone - the area just the right distance from a sun to potentially support life - and with the faint signal of water in its atmosphere.

Stephen Hawking, the world's most famous living scientist explores the greatest mysteries of the cosmos. In three landmark instalments he reveals the wonders of the universe as never seen before. Definitive, provocative, surprising, and beautiful, Into the Universe with Stephen Hawking is a fascinating look through the mind's eye of one of the finest brains on the planet. In 'Aliens' Hawking considers one of the most important mysteries facing humankind - the possibility of alien, intelligent life. He leads us on a journey rendered in eye-popping detail, from the moons of Jupiter to a galaxy maybe not so far, far away. We will meet possible aliens and wonder at their form, we will delve into the very principles of what it is to call something alive, and we will calculate the likelihood of 'contact' being made.

The hunt for aliens is on! After a distinguished career in cosmology Professor Martin Rees, the astronomer royal, has taken up the search for extra-terrestrials. Looking for aliens is no longer science fiction - it is a question that's engaging some of the greatest minds in science." As our knowledge of the universe has increased, we're getting closer to answers. Many scientists now think we live in galaxy with a billion Earth-like planets, many of which may be teeming with life. But what kind of life? Has anything evolved into beings we could communicate with? This film gets inside the minds of the scientists considering one of the most exciting and profound questions we can ask - are we alone in the universe? Professor Rees thinks we may have our idea of what an alien is like all wrong. If he's right, it's not organic extra-terrestrials we should look for, it's machines.

With more board configurations than there are atoms in the observable universe, the ancient Chinese game of 'Go' has long been considered a grand challenge for artificial intelligence. On March 9, 2016, the worlds of Go and AI collided in South Korea for an extraordinary best-of-five-game competition, coined the Google DeepMind Challenge Match. Hundreds of millions of people around the world watched as a legendary Go master took on an unproven AI challenger for the first time in history.
AlphaGo chronicles a journey from the halls of Cambridge, through the backstreets of Bordeaux, past the coding terminals of DeepMind in London, and, ultimately, to the seven-day tournament in Seoul. As the drama unfolds, more questions emerge: What can artificial intelligence reveal about a 3000-year-old game? What can it teach us about human mind?

The 1980s was a time when artists in both the UK and US were delivering powerful social commentary in their songs. Dylan Jones selects some of the finest alternative voices from this era. From The Cure on Top of the Pops at the beginning of the decade to The Stone Roses' debut TV performance in 1989, this episode takes a comprehensive look at the alternative music of an entire era. It also features powerful live performances from Billy Bragg, Tracy Chapman, Bronski Beat and The Selecter. In addition, there are archival gems from Pixies, The Smiths, Suzanne Vega, The Fall, REM and many more.