For most of the Earth's history, life consisted of the simplest organisms; but then something happened that would give rise to staggering diversity, and, ultimately, life as complex as that which we see today. Scientists are still struggling to figure out just what that was.
2015 • Nature
We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar mass black holes form when a very massive star dies, and its core collapses. The core has to be more than about 2.8 times the Sun’s mass to form a black hole. Black holes come in different sizes, but for all of them, the escape velocity is greater than the speed of light, so nothing can escape, not matter or light. They don’t wander the Universe gobbling everything down around them; their gravity is only really intense very close to them. Tides near a stellar mass black hole will spaghettify you, and time slows down when you get near a black hole — not that this helps much if you’re falling in.
Forget the big bang. The real moment of creation was the Cosmic Dawn - the moment of first light. This is the scientific version of the story of Genesis. The big bang gets all the credit for creating our universe. But in fact, the universe it gave was dark and boring. There were no stars, no galaxies, just a vast, black fog of gas - the cosmic dark ages. But, after a hundred million years of nothing, came a dramatic moment of transformation - the Cosmic Dawn. It's the moment the first stars were born, the moment that lit up the Universe, and made the first structure and the first ingredients of life. This was the real moment of creation. Astronomers are now trying to witness the cosmic dawn. For the first time they have the tools to explore the very first stars of the universe and to tell the scientific story of our creation.
When Neil Armstrong stepped onto the moon in 1969, America went down in popular history as the winner of the space race. But that history is bunk. The real pioneers of space exploration were the Soviet cosmonauts. This documentary combines rare and unseen archive footage with interviews with the surviving cosmonauts to tell the fascinating and at times terrifying story of how the Russians led us into the space age. A particular highlight is Alexei Leonov, the man who performed the first spacewalk, explaining how he found himself trapped outside his spacecraft 500 miles above the Earth.
2014 • Astronomy