Black Holes: Crash Course Astronomy #33

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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.

Crash Course Astronomy Poster:

Table of Contents
How Stellar Mass Black Holes Are Formed 1:03
The Core 1:43
Nothing Can Escape Once It’s Inside 2:29
Gravity Intensifies The Closer You Get 3:33
Spaghettification 6:01
Time Will Slow Down Near A Black Hole 8:01

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White Dwarf Pulses Like a Pulsar [credit: NASA, Casey Reed]
Swift Reveals New Phenomenon in a Neutron Star [credit: NASA’s Goddard Space Flight Center]
Black Holes – Monsters in Space [credit: NASA/JPL-Caltech, Wikimedia Commons]
What if the Sun became a black hole? (artist’s impression) [credit: ESA/Hubble (M. Kornmesser)]
Black Hole Animation [credit: NASA/SAO/CXC/D.Berry]
Star Destroyer [credit: Space Telescope Science Institute (STScI) and NASA’s Goddard Space Flight Center]
Black hole deforms space [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)]
Black hole close-up (artist’s impression) [credit: European Space Agency, NASA and Felix Mirabel (the French Atomic Energy Commission & the Institute for Astronomy and Space Physics/Conicet of Argentina)]


Akkeio Pather says:

what if the universe only exists because we are looking at it

Saahibul Ali says:

doesn't dark matter doge light so dark matter is faster then light

God is an atheist says:

I am very disappointed, of all the explanation about black holes in youtube no one mentions the scientist who actually inexorably proved the existence of black holes, Chandrashekhar, I had hoped crash course would be different. Not even a mention of the "chandrasekhar limit". I mean come on.

Shadow Sweetheart says:

Whatever happens in a Black Hole, STAYS in a black hole.

Lulu, Drinker of Coffee says:

"What ever happens in a black hole, stays in a black hole"

So what you're saying is that at a black hole's core, there's a cosmic Elvis impersonator ready to officiate your shotgun wedding in a drive-thru chapel.

Gotcha, I'm sooooo going to ACE any astronomy exam.

Sandy Aego says:

With all such amazing discoveries and science, Apple calls the earbuds innovation?

Hannah Shea says:

one time in a science lecture I was discussing spaghettification with a classmate and my professor irritatedly asked if we'd mind sharing our discussion with the class. I did, and he said he'd never heard that term before..

S.A. B says:

guys, these courses help keep me safe from homosexuals.

Patrick Hodson says:

They're acting like escape velocity doesn't depend on how far away you are…

tudor obretin says:

what if we could make a camera that stays in that point where time begins to tick slower for the camera and faster for the universe(and assume signal from that camera could travel back to us) We could see the future ta da:O

MinecraftBiss says:

i like how the gravity is so great that time would pass so fast in a black hole that would would literally be fried by just time PASSING BY

Xavier Lee says:

Knowledge always works.

Govinda Dasu says:

The particles leaking out note seems fishy/interesting.

sajid akram says:

if falling matter takes forever or a trillion yrs to fall in cos of slowed time, then blackholes 30billion masses which formed 12billion yrs ago, have no way eaten billions of masses in 2billion yrs after big bang, and thats without the other trillion yrs needed on top to eat matter.

Abeshik Vilekar says:

could you make a video about quasars

EricX 73 says:

they can't be that dangerous. Matthew McConaHegy escaped one in interstellar…

David B Jacobs says:

So you would die instantly….and live forever.

Jeremiah Noar says:

For kicks and giggles, say your in a rocket ship that can travel the speed of light +1. Would it escape the even horizon then?

Blueberry Peridot says:

Isn't it possible there are tiny particles of mass that can escape the black hole…

IanHimself says:

Black holes are said to be the creation engines of the universe. Please explain how and why in a future episode.

KnightCraft 130 says:

nothing can stop the collapse? what about superman

Aziraphale686 says:

I love how most of the questions Phil asks, he answers with "well you would die, but you would die in a very interesting way"

hallod1 says:

black holes dont even exist, what a lie.

ostrich man says:

It disintegrate's u into nothing.

ostrich man says:

(But U DIE)

ostrich man says:

i think Black holes are wormholes to other dimension. (Like my comment if you agree :D)

KerayZ says:

How exactly do you measure a black hole?

JosephHF says:

Is it just a coincidence that the minimum stellar mass required to form a neutron star is exactly half that to form a black hole, or is there a good reason why this should be the case?

Harry Ward says:

Does this 'space-time fabric' have any elasticity? Is that even a thing?


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