There's evidence that dark matter makes up 85% of all the matter in the universe. We can see dark matter holding galaxies together and ripping other structures apart, we even see it bending light. Dark matter itself has been around since the beginning of the universe. Without dark matter, we wouldn't be here. But if you can't see dark matter and if you can't touch it, does it really exist?
Dark Matter is thought to be the cosmic glue that holds the universe together, yet the search for it continues to eluded scientists today.

Cosmic rays capable of destroying human DNA are hurtling through outer space like subatomic bullets, causing space crews radiation damage.
Cosmic rays are intergalactic alien interlopers on our Milky Way. But the source of their power is a mystery. Are they coming from other galaxies? Are they coming from things in between the galaxies? Where do cosmic rays come from? Truth is, the most powerful ones, we haven't got a clue. The race is on to solve the mystery of the fastest particles in the universe.

The tenth season of this acclaimed series. A users guide to the cosmos from the big bang to galaxies, stars, planets and moons. Where did it all come from and how does it all fit together. A primer for anyone who has ever looked up at the night sky and wondered.
In the first episode, new astronomical research is beginning to reveal an invisible scaffold of dark matter known as the Cosmic Web, an intergalactic network that transformed the Universe from a chaotic Big Bang into the structured beauty of the present day cosmos.

Time i s a concept which is so familiar, and yet recent discoveries have revealed it to be far stranger than we could have possibly imagined. In the final programme in the series, Brian explores the enigma of time - a phenomenon we take for granted but which is one of the biggest mysteries in the universe. He recalls highlights from his TV series that touch upon this conundrum.

Brian takes a fresh look at the concept of gravity, revealing it to be far more than just the force that makes things fall to the ground.
In the last three years, we've made profound discoveries about the nature of gravity and the way it behaves, and how this relates to the origin of the universe and strange things like black holes. Our theory of gravity has become the attempt to understand the nature of space and time.

Of all the objects in the cosmos, planets, stars, galaxies, none are as strange, mysterious, or powerful as black holes. Black holes are the most mind-blowing things in the universe. They can swallow a star completely intact. Black holes have these powerful jets that just spew matter out.
First discovered on paper, on the back of an envelope, some squiggles of the pen. The bizarre solution to a seemingly unsolvable equation, a mathematical enigma. Einstein himself could not accept black holes as real. People didn't even believe for many years that they existed. Nature doesn't work that way. Yet slowly, as scientists investigate black holes by observing the effect they have on their surroundings, evidence begins to mount.