Down to the Earth's Core • 2012

11:54

Today on Crash Course Astronomy, Phil explains comets. Comets are chunks of ice and rock that orbit the Sun. When they get near the Sun the ice turns into gas, forming the long tail, and also releases dust that forms a different tail. We’ve visited comets up close and found them to be lumpy, with vents in the surface that release the gas as ice sublimates. Eons ago, comets (and asteroids) may have brought a lot of water to Earth -- as well as the ingredients for life.

21 • Crash Course Astronomy • 2015 • Astronomy

42:01

Asteroids strike, planets collide, black holes blast out death rays, volcanoes erupt and ice engulfs the planet. These are the universe’s weapons of extinction. They’ve happened before - wiping out entire species, and they will happen again. Are we next?

S3E6 • How the Universe Works • 2014 • Astronomy

10:27

Will resources on the Moon be the determining factor in whether the next human destination in outer space is Mars or the Moon? Google Lunar, Space X and other private industry efforts may lead the way.

S1E5 • Destination: Moon • 2016 • Astronomy

5:45

The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.

Veritasium • 2014 • Astronomy

9:41

The Mars InSight lander is on a 6-month journey to the Red Planet, with hopes of uncovering some of our planetary neighbor's secrets. Digging deep into Martian soil, the lander will measure marsquakes and also study the deep interior of Mars - perhaps revealing the origins of the planet.

Breakthrough • 2018 • Astronomy

0:00

In this episode, they investigate whether we should really be giving up bacon and sausages, after new research suggested they're bad for us. The programme explores why eggs, for years demonised as unhealthy, are now firmly back in fashion and apparently now about as healthy as you can get. Could butter or dripping be next? Plus why white bread isn't necessarily as unhealthy as assumed.

S1E4 • Food: Truth or Scare • 2016 • Astronomy