Black Holes: Crash Course Astronomy #33

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.

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Chapters:
Introduction 00:00
How Black Holes Are Formed 1:03
Misconceptions About Black Holes 3:05
Stellar Mass Black Holes 5:03
Spaghettification 5:50
Black Holes Warp Space-Time 8:00
Review 11:07
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PHOTOS/VIDEOS

[michaelconstantind.l.mendo]

"The Universe is under no obligation to obey our preconceptions. "

That's beautiful and terrifying at the same time.

[TheFireflyGrave]

Black holes, The Event Horizon, and Spaghettification. Astronomers really know how to name stuff.

[Elrond_Hubbard_]

I've got it.

The only way to survive falling into a black hole is to be _made_ out of spaghetti, because if you already are spaghetti, how can you be spaghetified?

[MrInitialMan]

"The core of the star is about to go bye-bye." My FAVOURITE line in this series.

[DodgimusPrime]

"As you hit the event horizon, all of time would pass."

Me: "All of...?"

"ALL OF IT."

[sid]

If I had to fall in a black hole, I'd do it twice. Once looking directly at the black hole, and once looking out into space.

[Filippirgos]

Today the history was made, the first picture of a black hole ever has been captured !

[kem]

I'm not even watching this for a class I just love astronomy and our school in Ohio doesn't provide the course :(

[dorkmax]

Only 4 years after this video was released, a team was able to composite an image of Messier 87 and it's supermassive black hole. We are an incredible species

[joshuahellauer]

Ok, the gig's up. We know you're Vsauce's brother.

[sapphael.]

That's just freaking me out! The idea that as you fall in ALL OF TIME passes before your eyes...

[WhosFaulty]

new uploads from this series is my favourite time of the week

[cholten]

No love for PBS Space Time? Would have been the absolute ideal time to point people over there :-)

[chibinyu]

"The universe is under no obligation to obey our preconceptions.." The best quote ever! <3

[ffggddss]

Phil: Thanks for the incredible ride!

Just two things I might (or might not) add:

1. Tidal "spaghettification" is just as much about transverse compression as it is about longitudinal stretching.

2. An alternative, and perhaps even neater way to explain the inability of anything escaping from inside the event horizon, is that while outside it, the radial direction is spatial, inside it, the radial direction is time! And forward in time points toward the central singularity. So escaping from inside, is exactly the same as traveling backward in time!

[Connarthian]

Actually, I think that falling into a black hole is somewhat a romantic idea now. Falling in, I would see everything happen. All of the future. The price is life. That's frickin' deep man.

[CuppaGi]

My favorite astronomical object.
I need to know if you'll be covering the theory of White Holes.

[strmanballtouch]

"hole in space, very very frightening me" - Albert Einstein

[MrTmm]

8:50 Einstein was right, he was right a lot….”
I love it!

[mercybellafiore]

"All of time would pass. ALL OF IT."