The Unruh Effect • 2018 • PBS Space Time

89:09

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

10:35

Last week we covered multiple star systems, but what if we added thousands or even millions of stars to the mix? A star cluster. There are different kinds of clusters, though. Open clusters contain hundreds or thousands of stars held together by gravity. They’re young, and evaporate over time, their stars let loose to roam space freely. Globular clusters, on the other hand, are larger, have hundreds of thousands of stars, and are more spherical. They’re very old, a significant fraction of the age of the Universe itself, and that means their stars have less heavy elements in them, are redder, and probably don’t have planets (though we’re not really sure).

35 • Crash Course Astronomy • 2015 • Astronomy

49:17

The story of how we discovered Dark Matter and what we do and don't know about this mysterious substance. Did Vera Rubin discover the glue holding galaxies together? What composes dark matter? What are Dark Stars and what is super symmetry, the potential answer to the questions around Dark Matter?

4 • Cosmic Front • 2014 • Astronomy

14:44

66 million years ago, an asteroid slammed into Mexico’s Yucata´n Peninsula, causing a dinosaur mass extinction. With over 700,000 asteroids in space, what's in store for humanity and our planet if it happens again?

Breakthrough • 2019 • Astronomy

12:35

Thanks to the wonders of physics, astronomers can map a timeline of the universe’s history. Today, Phil’s going to give you an overview of those first few minutes (yes, MINUTES) of the universe’s life. It started with a Big Bang, when the Universe was incredibly dense and hot. It expanded and cooled, going through multiple stages where different kinds of matter could form. It underwent a phenomenally rapid expansion called inflation, which smoothed out much of the lumpiness in the matter. Normal matter formed atoms between 3 and 20 minutes after the bang, and the lumps left over from inflation formed the galaxies and larger structures we see today.

44 • Crash Course Astronomy • 2016 • Astronomy

44:01

Relive some of the most unexpected accidents in spaceflight and meet the astronauts who had to fix them on the fly

S1E3 • Space Disasters • 2020 • Astronomy