The Black Hole at the Center of Our Galaxy: Don't Panic!
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- เผยแพร่เมื่อ 15 ต.ค. 2024
- SciShow Space explores the supermassive black hole spinning at the center of our galaxy, and how we’ve all learned to live with it in harmony.
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I love how he put "Don't panic" at the end of the title:)...Hitchhikers guide!
Neeeeeeeeerd!
Coincidentally, I'm currently visiting this supermassive black hole, but I'm staying in safe distance. However, the problem is that it messes up my upload schedule : In my timeline, I uploaded my last video two earth weeks ago, in yours it's much longer. Sorry, subscribers - I should have thought of that.
Ooooh, that explains it then XD
Wrong place to say that, Zogg! But as a subscriber of your delightful channel, I do hope you will return to amaze us with alien knowledge
Time dilation again Zogg? This is starting to feel as a ritual of yours, weren't you exposed to earthling culture too much?
Please come back to us, Zogg! If you start now, you'll be back in time for Christmas.... of 3714.
no porblems there, Zogg. Although, Watch out for Massive Hurtling Objects and bring back some pics of your trip. Would be an interesting view.
You guys deserve a much greater audience!
I always assumed we were slowly being consumed by "Sagittarius A*", I'm glad I was wrong. Not that it ultimately matters the time and space are too vast to affect our lives in real-time.
+BigBoss Don't worry. There is a black hole traveling at Sub-Relativistic speeds towards the solar system that will eventually destroy us free of charge.
Chaotix Fox Wait a second...are you talking about Donald Trump??? no wait he'd never do it free of charge, he'd totally charge us for it. So where'd you hear about the blackhole?
BigBoss I was just looking up stuff about black holes and found that some black holes have been observed traveling in our(general) direction. I remember the speed since I converted it from MPH to Mach, and notices it was Sub-Rel.
Chaotix Fox Wow that's fascinating, I'm going to do some research on it. I've heard about "rogue black holes" that move around. But never one any where near us, but then again we can't detect everything around us so it shouldn't be that surprising.
We still could be, we might just be so far away that the amount closer we get over time is so negligible that we can't even measure it
Don't Panic ey? That would be a good phrase to put the front of a book... maybe flashing, in large bold letters..
Maybe on an encyclopedia?
I have it imprinted on my towel, which I carry around with me everywhere.
Maybe he wants us to watch it to get more views 😂
I really like the intro animation for SciShow Space. It's colorful and dynamic like our existence in this universe.
The 10 second explination of tidal forces in this video explained more about how the tides work on earth then anywhere before.
It seems so simple to me now as to why we have tides, I don't know if you have made a video on it previously but if not please make a video on the tides and how they are created by our moon!
Unfortunately, he conflated the event horizon with the Roche Limit. The event horizon is basically the point of no return. The Spaghettification point he described where objects start to tear apart is the Roche limit. and around planets is where an orbiting moon will disintegrate into a ring.
Thanks so much, I have bad paranoia so I get worried about stuff like this but now I'm not worried at all. I subscribed and turned on the notification bell!
"Huh. So if we're orbiting the sun, what's our sun orbiting?
...OH GOD, IT'S TERRIFYING"
Pretty much my reaction upon first learning about host of the Milky Way Galaxy party.
HalcyonSerenade what if I told you that our entire galaxy (along with everything in the Virgo Supercluster) is being attracted to a mysterious something (that some scientists believe is yet a mor massive black hole) far away in the universe?
HalcyonSerenade barycenter....
Every planets in our solar system(includes the sun) orbitting in the barycenter
Our sun is not orbiting any thing as we know
The Sun isn't the biggest boss
You have videos on all the topics Ive been waiting for videos on and now I think Im in love with SciShow Space.... thank you
One nitpick - the event horizon and the point where spaghettification would occur have nothing to do with each other. Though it's understandable - even Stephen Hawking once stated the same misconception.
The event horizon is simply the point where the escape velocity exceeds the speed of light. Spaghettification occurs where the gravitational attraction towards the black hole is increasing so fast that there is a huge gravitational gradient across the incoming object.
The odd thing about black holes is that the event horizon diameter increases linearly with mass. The gravity gradient (and the point where it is steep enough to rip things apart) has an inverse square term in it.
Small black holes will therefore spaghettify objects further out compared to the event horizon while massive black holes are the opposite. en.wikipedia.org/wiki/Spaghettification#Inside_or_outside_the_event_horizon
Fun fact: for a supermassive black hole, the gravitational gradient at the event horizon would be very low. In fact, a person in a well-built spaceship could theoretically survive the crossing of the event horizon and not even be aware it has happened. Of course, once past the event horizon, the astronaut's eventual doom is certain.
kilroy1964
That's incorrect for a couple of reasons.
For one, you absolutely need to achieve escape velocity to escape a gravitational well. You need a certain quantity of deltaV to escape and that is regardless of whether you achieve that deltaV quickly and coast out or are thrusting the whole way. Once you are inside the event horizon, it does not matter how powerful your engines are, you cannot leave.
Further, there are no stable orbits inside the event horizon so you can't even hold place. Even light will eventually spiral down to the center.
So Dan, what you're saying is if I have a jet pack that accelerates me to measly 20km/h away from Earth and then only accelerates me enough to counteract gravity and friction, that I wouldn't escape Earth's atmosphere?
Dan Heidel if the event horizon of a black hole is when escape velocity is equal to c, couldn't you still hold a stable orbit as orbital velocity < escape velocity for a given distance? furthermore what you can do is make a burn below the event horizon to raise your apoapsis above it (but your still orbiting it so your velocity < escape velocity and c and therefore you are not violating relativity). once you reach said apoapsis above the EH, you can make another burn to raise your periapsis above the event horizon. Once here you can make another burn to reach escape velocity which is now < c since your above the EH and viola, you have successfully escaped from beyond the EH without violating relativity. of course this will require a phenomenal amount of dV but the point is that the astronaut's doom is not certain.
PajamaMan Assuming that the jetpack has magic, infinite fuel, yes, it would. That's because it's imparted an initial deltaV and you're continuing to accelerate at roughly 9.8 m/s^2. Of course in practice, such a rocket would need an ocean of fuel but let's ignore that for now.
You have to look at this problem from first principles. You're being pushed down by a constant 9.8 m/s^2 of gravitational acceleration. That gravitational field drops off as an inverse square of distance from the Earth.
You have to integrate that acceleration against gravity from 0 to infinity and that gives you the total velocity you need to escape. The most efficient way to escape is to gain that velocity instantaneously since then you are wasting a bunch of thrust fighting the 9.8 m/s^2 gravitational acceleration for as short a period of time as possible. However, as long as your engine ultimately brings you to escape velocity, you will leave - it doesn't ultimately matter how you do it.
A black hole has a total escape velocity greater than c. That is definitionally impossible for any material object to do. It doesn't matter how fast or slow you do your acceleration, relativistic effects make it so that it rakes an infinite amount of energy to get that deltaV.
Wouldn't the light inside the spaceship begin traveling exceptionally odd paths once the event horizon was crossed?
What about the people that don't believe in black holes? Do they feel the gravitational pull of one?
No the black hole just kills them first for being so dumb.
If a tree falls in the forest and the only person there is deaf guy, does the tree still make a sound?
God created black holes
GarudaLegends Proof? plz :)
Holland Novak oh ok. Let me upload the video of him creating it, because obviously i was there with my camera.
I don't want my noodle to be cooked! :'0
im gona ask the chinese guy lulu whos confused for a woman often of ownagepranks channel if he cooks his noodle n ballsack often
Who was panicking? Even if we was being sucked in it wouldn't be in my lifetime, or indeed in the lifetimes of any generations I witness in my own lifetime.
Or whatever, it would probably not be that painful and something else would kill us before that, probably in a quick way.
I'm more concerned about what another man could do to end my life rather than what giant entity could make spaghetti out of me. As interesting as it is knowing what could happen, I'm not losing sleep about it. If anything I'm only fascinated by the scale of everything beyond our little planet, and how i wish I could witness this scale of other world's with my own eyes.
It would still be pretty depressing if you knew that at least some time after your lifetime, the whole galaxy would be destroyed, along with all of its humans.
Even at the speed of light we're thousands, if not millions of years from the black hole. And the earth is moving in any direction at barely a fraction of that speed. So no, mankind will be long extinct or long moved on from planet earth before the planet becomes a serving suggestion for ragu.
Vadix Vadexi That's a certainty already. Whether it happens in our lifetime, our children's lifetime, or at the end of the sun's life, who could say. A natural disaster, nuclear war, etc. could all lead to end of the galaxy. Or, the sun going out will certainly take our world down.
Where's my spaghetti?
Black hole: Gurp.
I'm hungry now.
You are spaghetti
One thing faster than the speed of light: the narrator´s speech. Bet his dying screams would escape the pull of the Event Horizon.
"Here on earth the gravitational pull of a person standing 30ft away from you is 10.000x stronger than the pull of the supermassive black hole"
add another 30ft and make it 100.000x when case of mother-in-law ._.
Great video... galactic centre black holes now make MUCH more sense.
Trust me, I have spaghettified a lot of Kerbals...
I love playing KSP!
Gilian Rüsterholz long Live KSP
whats a kerbal
@@bberzamin the hell is ksp?
@@electricpants8196 kabel special provocations?>
Not gonna lie, this is the most informative video I have seen on yt about black holess's ins and outs. explains things such as the even horizon and why it's black. Find it strange how we don't know how the supermassive ones form
Literally makes me panic!
bah, humbug. next you're gonna tell me there's a skeleton hiding inside of me
Cuda FX There's a skeleton hiding inside of you.
There is really a supermassive black hole in the centre!
And also it inactive at the moment.
It will awaken during the collision between our Milky way and Andromeda galaxy.
It's true
2:37
Hmmmm....
The symmetry in this model draws out an EYE!!!
Super massive black hole is not 93 million miles away. ITS WAY FURTHER
Yea, I think he accidentally used the Earth to Sun distance for that part.
he does say its 26000 light years
It has a probability of infinity to minus one of being a distance of 42 lightyears away from earth
9112274 can I tell you bout space engine
A couple million au's from earth I thinm
Serious question. If you could be in a spaceship (or on a planet) far enough away not to be sucked into the black hole, would you actually see anything? Because if light can't escape it, then I'm assuming there would be nothing for you to actually see.
highdough Indeed; it would appear as a solid black sphere (or oblate spheroid if it's rotating) against the background of stars, unless it were orbited by an accretion disc.
That is an interesting question. I have heard that strange things can happen when you're near black holes. Generally, space/time is out of whack. When you see an object or a person falling into black hole, it will eventually stop falling from an observer's perspective. But the object itself will continue to fall into it. From a perspective of the falling object would eventually see everything around it will dilate and distorted and eventually be able to see itself falling into it. When looking back, you'd be in a "white hole" where everything seem to appear.... White. But this is just a speculation based on all mathematics.
Space around the black hole would also look very strange due to the gravitational lensing. Kind of like a lens with a dark spot in the middle that smudges and distorts what is behind it. You wouldn't actually 'see' anything, not even a black object - because there is no object to see. It is a singularity from an outside viewer's perspective. There would be nothing visible except strangely distorted renditions of whatever was behind it.
The movie interstellar has some scientifically accurate visualizations of what gravitational lensing looks like, it's really cool
Please confirm:
A black hole doesn't weigh more than it did before collapsing. No mass was added. Instead, the collapse means the surface sort of "retracted". Retracted so far that it sunk below the event horizon.
The star which existed pre-black hole would have the same gravity at up to the surface of that star. It too would have had a theoretical event horizon, SORT OF, except the mass was distributed and not concentrated (like a black hole's is). But this "event horizon" would be inside the star, and the star's mass is better distributed, and so no physical event horizon would actually exist. Only by concentrating the mass into asymptotically high density does an event horizon form.
An object orbiting the massive star at distance X would also orbit its black hole "form" at the same distance (assuming the masses don't change).
This is why the new reboot of Star Trek made me scoff. Enterprise orbited an object before it became a black hole, yet once it became a black hole its gravitational pull (at the same distance) magically increased. That seems to be a physics 101 fail IMO.
malignor Confirmed.
id imagine a black holes mass would grow in time with more mass getting trapped inside.
wouldnt explain the star trek effect tho.
yunthi It will grow in time, until its supply of matter runs out and the microwave background cools enough for the black hole to net radiate energy away in Hawking radiation.
was also thinkin that even if the gravity does not increase in the transformation, still solar winds would probably cease, and the matter in that solar wind would start gravitating towards the black hole.
not a huge difference perhaps but still some minor change.
I am not sure if I understood your comment and if I did, I apologize in advance. There is a massive misconceptions about what gravity is. To this day, we are still trying to figure it out but I think Enstein is on a right track. Gravity itself does not pull anything. From what I understand from general theory of relativity, space and time is relative meaning they are basically different side of a same coin. When we say gravity, we are actual seeing an effect of an object with mass being affects by another object that curved the space. So in a way, objects are basically moving in an efficient straight line through a curved space. So when we talk about black hole, when an object with mass becomes a singularity, space is compressed into infinite degree. So an object going past it thinks it is going straight but actually the space is so curved, everywhere you go leads to the singularity. And I think this is where we got things confusing with "event horizon" and "escape velocity". Past the event horizon, increasing velocity does not make sense because everywhere you go will lead you into singularity. So when we say a stellar object having event horizon is kind of wrong because those object do not have a singularity where it warps space to a same degree of black hole. So stellar object do have escape velocity but not an event horizon. And black hole does have event horizon but not an escape velocity. I hope that made sense.
I love that the first picture of a black hole they showed is the same exact picture that has been my computer screensaver for months now.
1:55 umm...isn't 93 million miles just 1 AU?
+Eric Southard yes
One.. Australia?
PneumaticFrog Au stands for Astronomic unit and is the distance between the earth and the sun at roughly 92.955807 miles.
+MartinG. No, it is one Australia, dont lie to him bro.
MartinG. yeah stop lying
one thing i don't get it, once you get past the event horizon the escape velocity is greater than the speed of light. so that would mean that if you'd fall to the center of the black hole your speed would be faster than the speed of light right?
Just the other day I was having a conversation about the impending Andromeda/Milky Way collision and this seems like a perfect time and place to ask about it. As I understand it, most solar systems in both galaxies would pass through unharmed due to the great distances between celestial bodies. My friend insisted that the black hole at the center of Andromeda would spell disaster for the entire galaxy, but as you've mentioned in the video, at galactic distances the gravitational pull of a black hole is really quite miniscule.
My question: What happens when two galaxies collide?
all that needs to happen to spell doom for us, is that our orbit around the sun gets put out of balance. Doesn't seem all that unlikely to happen.
Pivitrix That would indeed cause problems, but that's harder to do than you think. Assuming Andromeda's black hole doesn't come particularly close, a star would have to come *very* close, close enough that the distance from the Earth to the sun is non-negligible in comparison. For reference, the nearest star to us is about 253,000x farther away from us than the sun. It would probably have to be like < 1,000x in order to have a serious effect.
Ryan Harding It always amazes me just how big and mostly empty space is.
But if you look at a simulation of the crash, the galaxies are slingshotting back and forth through eachother before eventually settling down. I'd say there are pretty big forces at play there, i just have a hard time imagining our solar system being left to itself without interference through all the madness.
Although it would take a very long time and isn't as dramatic as it looks like.
Vsauce made a video about that called "what will we miss"
Ryan Harding There will be a huge burst of star formation as the interstellar mediums of the two galaxies collide, but largely nothing will happen - space is so incredibly empty that the gravitational interaction between stars is much more likely to fling stars out of the galaxy than collide them. The black hole will eventually emerge with the one in the centre of our galaxy, which will likely release a lot of energy, although likely not harmful to someone as far out as us.
Very interesting, thank you! It's a pity the video wasn't longer, but I understand.
as the black hole sucks up more mass, won't it eventually become larger and more scary?
I don't think so, the objects it sucks up are crushed to a point it would not affect the black holes size, not to mention energy is released in the form of Hawking radiation
coolguyman16 Yes, as the black hole grows in size, its gravitational pull increases. However, it's actually fairly difficult for a black hole to gain mass. They are extremely small targets for something else to hit. The vast majority of stuff around the black hole will just end up orbiting it rather than falling in.
coolguyman16 But actually, black holes are getting scarier by sucking up things. The mass of a star that enters a black hole is not lost, and even though Hawking radiation removes bits of the black hole over time, if a stellar black hole consumes more than it loses (and it really just loses tiny amountss of itself), it gets bigger, heavier, scarier and even darker (Stephen Hawking himself said that tiny black holes (+/-mass of the Himalaya) would actually glow from their radiation.
Yes, but not by much. Sagittarius A*'s event horizon is only 0.4 AU from its center. The largest known black hole, S5 0014+81, has an event horizon 1805 AU from its center. That sounds like a lot, but considering a light year is 63,000 AU, even the scariest black holes are _tiny_ compared to the size of the Universe.
Dan Heidel But in the accretion disk, wouldn't the particles lose velocity due to their insane friction? And if that happens, wouldn't it cause orbiting mass to start falling into the hole? Btw nice to see you again :)
Zog, question. if 1) nothing can travel faster than light, and 2) past the event horizon, gravity is so strong that nothing traveling at light speed or slower can escape it, then 3) how it a black hole capable of emitting energy bursts? A curious mind.
If our galaxy is orbiting the supermassive blackhole, what is the supermassive blackhole orbiting if it's even orbiting anything at all?
That's asking like what does our galaxy orbit around.
My best bet is that our galaxy is still flying away from the center of the universe, and that nothing yet exists that is so massive that it can force our galaxy out of course and into an orbit. Or that, if such a massive object exists, it's too far away for our galaxy to be affected by it in any significant way.
It's probably possible for two galaxies to orbit one-another, or one galaxy to orbit an other, but I think the galaxies would have to be "relatively" close to each other.
I don't think our galaxy is orbiting anything, dark matter is just keeping everything in place so to speak (even though the universe is expanding and galaxies are moving further away from us, with the exception of the Andromeda galaxy)
It isn't really orbiting anything but it is moving towards something. "The great attractor"... but even that unknown huge mass is moving toward something with even more mass. So our "tiny" super massive black hole will eventually orbit something too.
galaxies form clusters which means they form groups that orbit each other but on a scale so big i have no words for it. there are some small galaxies that orbit our galaxy and when galaxies combine (like ours will with Andromeda) the black holes will temporally orbit each other but these are on the scales so huge that they are only meaningful to type 2 or 3 post-human civilisations.
Imagine being on a planet that's in orbit just above the event horizon of a super-massive black hole... Damn it would look scary AF. Or what if a moon was orbiting a black whole, which was orbiting a super-massive black hole, and you were stood on the moon? Damn............ I wouldn't like to be there.............
there was a planet orbiting near a black hole in interstellar
MidoriFlygon I haven't seen it yet :(
I think a planet close enough to a black hole that you'd get a good view would be torn apart by the tidal forces mentioned in this video.
MidoriFlygon Unless you're on a page that is explicitly for talking about the contents of recent movies, posting openly about them is extremely inconsiderate, so please keep stuff like that to yourself in the future.
Jordan O'C watch it. it's amazing. like compared to other sci fi flicks out there, this one's so accurate and is based on actual theories, and it never patronizes and talks down to the viewer by dumbing down scientific explanations. obviously some parts are a bit of a stretch and a bit made up to fuel plot, but still it's a wonderfully made movie.
So if black holes are just super dense solid objects, what elements are they made from that makes them so dense?
penises ...
They're not exactly elements anymore. The core of a star is rather dense as you can imagine. At the end of a big star's life, there's a whole process going on that eventually causes the core to become even denser. The pressure increases, and more mass gets cramped into a smaller volume. This causes the gravity to increase, and the force to get stronger, and the pressure to get higher still. Etc. Normally there are other forces that can counter all this pressure, but if the star's heavy enough, they too fail, and the core fully collapses to within its own event horizon. Then the entire core just keeps on collapsing into itself, and the blackhole is born. The whole concept of the elements just breaks down in such conditions. We don't quiet know yet what form the mass in there will have taken after the collapse.
They're likely made of neutrons, but we don't know. We can't go to one.
Edit: Original comment deleted, read what Arceus said.
All hail Helix.
Black holes are more dense then the nucleus of atoms. So they can't be made of any elements we know of.
I remember in grade school there was this kid who found out about the black hole in the center of the milky way, and they started panicking and telling everyone about it as if they were announcing the end times. I, being a kid who was really interested in space at the time and knew more about it than the average grade-schooler, sat quietly and watched as my class went into panic mode.
If light can't escape from a black hole, wouldn't it be extremely light in a black hole? I wonder how bright things could get?
+Merlyn Schutterle
Nope. Even if you were conscious through the whole ordeal, you can't see the light because it's traveling away from you at the same speed you are, and once you're at the center, no light can "emit" because it can't escape the hole.
+Merlyn Schutterle If your flying into a black hole and turn around all you see is light being sucked in and in front ofyou its blaaack
If you turn around, you wouldn't see light either
you would. saw it on Vsauce
+GweiTheLeafChild Maybe I should just pick my banjo and not worry about things like that.
You should never use the comment "nothing can travel faster than the speed of light", rather nothing can accelerate to a speed faster than the speed of light. Keep the videos coming!
Vote for Pedro!
Hey Hank, why are most models of black holes 2D when they are spherical? And when visuals are shown of accretion disks forming, how come they form in a disc shape, and don't form like a shell around the black hole? And finally, where are the poles of the black hole that matter spews out of? Please help, really confused!
probably because making a sphere all black won't project to our eyes
in fact, any sphere projected on a 2d surface will appear 2d, it's not like a cube that can be shown at a good angle.
What if you're stuck between 2 equal sized black holes?
Well, if they are the same mass and you're exactly in the middle, they would be equally pulling on you. However they would also attract each other so you'd have two black holes flying towards each other and by extension, you.
If they were orbiting binaries, you could float there. But if you moved the slightest bit in any one, you'd fall out of unstable equilibrium and fall towards one of them. Good luck with that:P
kilroy1964
If they are orbiting each other, yes. However, the question seemed to imply two static black holes.
Dan Heidel you are incorrect. static implys they are motionless. it really depends on the distance between you and the two black holes. if they were static and not attracting eachother or attraction was ballanced by repultion or attraction in the opposite direction, if you were close enough you would be stretched in two directions due to spagettification down to what singularity remained which would stay in the middle.
yipfrr
I'm not sure why you're being so sure about this. This is a purely hypothetical question and so if the starting condition has stationary black holes, it has stationary black holes. If you bothered to read my first response, I explicitly stated that they would start moving towards each other. The statement of them being static also has nothing to do with spaghettification - it was in response to kilroy1964 stating that orbiting black holes would be in a stable configuration.
And you also have no basis for stating that spaghettification would occur. There is nothing in the question that states the distance between the black holes. The spaghettification radius occurs quite close to the singularity and can even be well inside the event horizon. Unless the black holes are starting quite close to each other, the tidal force on a person in the center would be tiny. Eventually, they black holes would get close enough do to a double spaghetification but at that point, both black holes would be moving at a significant fraction of the speed of light. So the spaghettification process would be incredibly brief and would probably not even finish before both singularities came crashing together.
Awesome video.
Nothing travels faster than the speed of light... hmmm... thats your belief today, I still dont think it makes sense that the "endless" universe has an ultimate speed which nothing can beat, and yet this speed is so incredible slow that it would take 100,000 years to just cross our galaxy.
Torben Rudgaard dont remember how, but you may want to research why light is the fastest speed you can ever get. Something to do with mass. So yea dont have an aguement over someone else's stupidity.
Torben Rudgaard An infinite speed of light would imply that all particles are massless and therefore experience no time. This means that the universe, at least as we know it, cannot exist as it would be infinitely large and it would take no time for light to travel through it as it travels infinitely fast. It just doesn't work.
Torben Rudgaard And yes the speed of light is very slow relative to the expansion of the universe, which happens faster than light at large scales. Perhaps in the very distant future we can find an explanation for why all this is.
Torben Rudgaard there is something faster then speed of light its called speed of dark google it
Nothing is faster than light in space. But interestingly enough space itself does expand faster than the speed of light.
I'm confused, he said the supermassive black hole was the size of the orbit of Mercury but that the event horizon was much larger. If we don't know what's inside the event horizon how do we know how big the black hole itself is? I thought all the mass was concentrated in a single point infinitely dense singularity at the center?
Oh baby don't you know i suffer,
Oh baby can you hear me moan
You got me under false pretences
How long before you let me go?
Hope you get it :)
I thought I was a fool for no one
Ooh baby I'm a fool for you
You're the queen of the superficial
And how long before you tell the truth
Freakin great song btw!!
+DJR agree 100%
Shyderr P It's playing in my head now :-D
FINALLY I found what I was looking for
a couple questions; 1. what happens if a 2 or 1 dimensional object approaches a black hole's even horizon? it cant stretch one end faster because it is only 1 plane,. 2. "nothing can travel faster than the speed of light" except gravity? so could we use gravity to travel faster than light? this is technically time travel yes?
SNiD4 Gravity moves at the speed of light. As for the 2- or 1-dimensional object, if placed correctly they won't experience spaghettification.
Thanks God...
Don't thank god, thank the universe.
@@TON-ou1rt Noice whats where your mommy little felia??
Well put sir!
There is one forty billion times the mass of the sun
And I am 66 billion times the size of the sun.
@@TON-ou1rt So how is M87 doing?
Still wondering if they're a mass from pulling in material, did a tucked spin thing, finally causing too much gravity, super whatevering the make up of the star(s), causing a meltdown thing, causing a super nova, finally spinning even more freely, (faster than the speed of light), leaving the look as if not lit while actually being super heated and having light, being too much for standard light to escape, puling light into and/or around itself, and rip tiding it away..
Until Andromeda comes crashing in...
x TROLLING x in 1 billion years mate
And andromeda will be eaten by our galaxy and we won’t be affected
I hope we are around to detect the gravitational waves from the 2 supermassive black holes colliding. that would be way cool. probably not though...
I'll kill andromeda.
I have a question for SciShow, recently they discovered the Higgs particle, and according to what i can get, this particle is of the boson type... So here is my question, the bosons are particles that transmit force, electromagnetism, gravity, weak force, etc. so if the Higgs is a boson and it explains mass... is mass a force also?
leandr0varela A gauge boson is a particle that carries one of the four interactions (strong, weak, electromagnetism and gravity from strongest to weakest). A gauge boson is a type of boson, which is a type of particle with integer spin, such as photons, helium-4 nuclei and yes, the Higgs boson. The Higgs doesn't carry a force, though, only mass.
Oh this sounds delightful
so, if the pull is greater than the speed of light, does that mean something falling into a black hole can move faster than light? What if it's light itself that traveling into the black hole? Will the light then move faster than light?
Started singing muse's super massive black hole half way through, got distracted, had to watch again to really hear
My professor discovered this black hole about 20 years ago. So cool!
You need a correction at 1:53 of the video. Earth and 'our' supermassive blackhole is more than 92 millions miles away, even Mars is over 200 million miles away (average).
Hey all! I am starting to get more interessted in space.
So is it because of a black hole that the galaxy looks like it's spinning? Meaning orbiting? And i know it is not the only black hole in our galaxy as they do appear after stars death? And that star also have to be quiete big enough?
And a black hole will always be at the center of a galaxy as it's the thing with the strongest gravitational pull?
I did read about a black hole in the center of our galaxy a long time ago but never paid any particular mind to it, but i am geting more interested in understanding how they work.
I am challenging myself right now by trying to see if my knowledge about black holes is good or not...
+LEGRAND I think you will find that the reason there is a black hole at the center of each galaxy is because it is a normal part of galactic formation. I read quite some time ago something like this:
[NB, Btw this is a rough sketch at what I remember and if anyone reading this has a much better understanding please feel free to correct me or to elaborate and improve upon this]
When enough material (mostly hydrogen gas) gathers for a 'proto' galaxy a black hole will form at the center of this mass making an accretion disc, consuming huge amounts of matter for a long time but also emitting lots of high energy radiation.
There is an opposition between the force of incoming matter being pulled by gravity and the force of the radiative pressure pushing back outward. The radiative pressure grows and grows as the supermassive black hole gets bigger until it finally is able strike an equilibrium and halt the rapid in-falling of surrounding matter.
By now the galaxy probably has gathered into something more compact and with more defined structure and it is in a stable phase of development.
For your first question, the spinning has to do with the gathering of all of the mass into more compact forms:
A very large cloud of gas gathers due to gravitational force slowly over a very long time and any tiny amounts of angular velocity it might have get amplified as its mass occupies a smaller and smaller volume, getting more and more compact and coalescing into things like stars, planets and black holes. So the spinning has to do with all the mass/matter, not just that of the black hole.
You are correct that black holes can appear after a stars death, and that a star must be heavy enough for that to happen (multiple times the mass of the sun but I don't remember exactly how many). If it is not quite that heavy then a neutron star can result instead
I hope this helps
Sagittarius arm or Orion spur? Been seeing a lot of science shows alternating between those... Are they the same?
Hey SciShow Space I think the graphic is incorrect. At ~1:56 it shows the distance between Earth and the black hole being 93 million miles.
I don't mean to knit pick but the distance between the Earth and Sagitarius A* you've put up in the video is wrong, you've mentioned that the distance is 93 million miles which is 1AU, the earth is 23,000 light years away which would make it 132 quadrillion miles away.
How and why do black holes evaporate? You can supposedly "starve" one into evaporation if it doesn't "eat" anything, so if everything in our galaxy is just orbiting it, how long before it evaporates? If it is "eating" stuff, does do we have an estimate on when it when it will eventually starve?
If I'm not mistaken, what scientists are trying to figure out is why galaxies are structured the way they are and spin around with extra energy without falling apart, aka Dark matter and Dark energy right? The black hole has nothing to do with everything spinning around it?
Astrophysicists have a great understanding of galaxy structures, though they are still doing a lot of research. Our galaxy spins due to conservation of angular momentum, from being a cloud with an initial angular momentum that is conserved when it forms into a disk. The central black hole is one central force of gravity, but it's really all the mass around the center that keeps it spinning. The spinning near the center is faster than what we would expect from the baryonic matter, so we suspect there is dark matter. Dark energy is something different; it is the part of the space energy density that accounts for the accelerated expansion of the universe.
God, i really love this guy.
holy shit, for a second in the middle of this video i had the strangest existentialist feeling ever, as i imagined in a split second a galaxy, dazzling with lights, and then zoom into a planet orbiting an ever speeding sun, as i sit in my chair in said planet watching this video as we sling around our own black hole.
So here's a question: For a super massive black hole, where the spaghettification won't occur right at the moment you cross the event horizon, wouldn't there be an absurd amount of light, like enough to fry everything and anything, right there, as the photons that crossed it, would be traveling at the speed of light, and basically be in orbit? Since they'd be traveling at the speed of light, and right at the edge where it's not enough to escape, they'd be stuck there, accumulating more and more from all sources of light? Or am I completely off base here?
Immediately liking this video because it's finally Hanks
I like your presentation style
In a different solar system closer to the center of the milky way, what is the possible effect and kind of environment if they are near that super massive black hole?
Isn't Sagittarius A* supposed to Jet outward soon? I'd heard it was going to be in a few years. Also Doesn't the Crab Nebula also have a Singularity?
I've got a question and I'm sorry if it sounds a little idiotic. But I got curious. What would it take to make Jupiter explode/ignite, and what would that mean to our solar system?
neino36 A _lot_ of mass. You could get some fusion if you increased its mass by a factor of one hundred, or you could just burn the hydrogen by increasing its mass by a factor of ten using just oxygen.
is it possible that the black hole could eventually stop spinning, and if not what kind of evidence do we have to confirm this?
How does an object with a gravitational force 10,000 times weaker than that of a human standing 30 feet away pull us in enough to keep us in its orbit?
Does it pull nearby things close to it, creating a larger mass with the black hole at its centre, and then this mass pulls more stuff in, eventually pulling us in? Are we held in place not so much by the black hole, but by all the stuff around the black hole, with the black hole simply at the very centre of the mass (comprised of tens of thousands of solar systems, etc.)?
By pulling on every atom in the solar system with that same force for millions of years. It may be a tiny force but it is acting on a vast amount of mass for a vast amount of time. The result is orbit.
Gravitational force drops with the square of distance so the mass of a human body a few km away will already only have a fraction of the pull of the blackhole tens of thousands of light years away. Scale that up to the solar system. The body is dominant over a tiny area, whereas the black hole is dominant for the system overall.
And this does not stop at the black hole. That, and the whole galaxy are gravitationally bound to the local group of galaxies by the same force, and the local group to the virgo supercluster, the virgo supercluster to Laniakea and so on.
I am pretty sure I found a mistake. at 1:52 you say the distance to the black hole is 93 million miles, but that is the distance to the sun. the distance to the black hole is around 1.6*10^14 miles which is 16 trillion miles. Correct me if I am wrong.
danytnt Their diagram is wrong.
One thing we’ll never know is if Black Holes are conscious or not, so I like to think of them as gigantic OG’s in space, chilling without fear.
Nice and funny video!!
so if the velocity to escape is faster than the speed of light but they do eject jets how are the jets coming from and moving away from the center without the jets moving faster than the speed of light at some point?
" Your noodle is essentially cooked" Yeah, I lost it there.
a thought just came in to my head, so you need an atmosphere or basically particles to hear sounds or for sound to travel through so if a black hole were to have a atmosphere of some kind for sound to travel around, what would a black hole sound like? i may be far off from what i am trying to say but basically i am wondering if a black hole would sound like a really low constant bass sound or maybe nothing at all
i thought this was pretty cool to think about
Christian Chaparro Well knowing that might not be possible, nothing escapes event horizon you can still (i guess) hear the accretion disk the sounds are made by em waves conversion not like physical conversion.
If I'm not mistaken, some mass must be pulled in past the event horizon. Approximately how much mass per unit of time is this at Sagittarius A? Do we know?
Me Moi I've tried looking up the information from you, but after reading doi:10.1038/nature10767 and doi:10.1038/nature10652 the only answer I can find is that the amount of mass per unit time is 'low', and it's apparently surrounded by low-density hot gas. Sorry I can't answer your question.
hank. Spaghettification is dependent on dg/dr (change in gravity) rather than g itself so it does not necessarily happen just beyond the event horizon. in fact, for small black holes, it can happen outside of it and for supermassive black holes you can theoretically survive just beyond the event horizon (ignoring all the high energy radiation and heat).
Hihellohi610 How would you survive inside the event horizon? The radial dimension is time-like, meaning that bits of you closer to the centre can't communicate at all with bits of you further out (that is, the future light cone of any object inside a black hole does not encompass anything farther out).
Yeah, he seems to conflate the event horizon with the Roche Limit. Orbiting objects get torn apart by tidal forces at the Roche Limit, not the event horizon. Light cones in Relativity are the reason why we focus on the event horizon.
Ok, a few problems here.
1. The tidal forces can absolutely do damage when you approach a black hole. What makes them so dangerous isn't their incredible mass, but the fact that you can get so much closer to them than you would anything else without hitting any surface. This allows you to get close enough so that the tidal forces will actually rip things apart. This generally happens long before the event horizon.
2. You can never cross the event horizon. due to relativity, the event horizon is not just the point where light can no longer escape, but it is the point where the universe, well, ends. as you approach the event horizon, gravity becomes so strong that space-time warps to the point that time slows down, and at the event horizon, stops. so you can never pass the event horizon because it is the point where time literally stops, and the universe ends. Pretty cool if you think about it.
the second part is completely wrong. From the outside perspective, your light would appear "frozen" if it wasn't red-shifted into invisibility, but you yourself are absolutely going to experience that event horizon. Time isn't this objective force that gets slowed because of gravity, GR says space and time are connected, and the speed of light is the absolute speed limit. When you start getting to close to the speed of light and around massive bodies, your clock ticks seem to slow to an outside observer, but you think their clock is ticking fast. Your clock never "stops" even inside the black hole itself.
This guy is the best host on the show
woke up and asked myself: What's in the center of the galaxy?
well thank bro you earned a sub
I've always wondered that if nothing can escape a black hole, why do tons of pictures, even 2 or three in this video, show the jet streams being emitted from the center of them? Are they above the event horizons and what makes them be pushed out instead of being drawn in?
Grant Brewer Those jets are above the event horizon and occur at the poles of the accretion disc due to magnetic fields and turbulence (which is astrophysics talk for 'we're not quite sure of the physics behind it but we know these things are responsible').
black holes are messy eaters. Everything gets sucked in so fast that a lot of the matter bounces off of other matter and gets carried by magnetic fields and shot off at the poles. That matter never actually enters the black hole
“It’s not that bad. It’s just called a supermassive black hole. Also it’s also 4millions times bigger than the sun. But don’t worry there’s ones 100million times bigger than the sun” what a rollercoaster in 1 minute
"TON 618" to my knowledge is the largest known Black Hole in the universe at 66 billion Solar Masses. Yeah our galaxy's resident Black Hole is a freaking tadpole compared to that.
Happy holidays Hank.
I have one question is a black hole just a thin layer in space and could you go behind it or is it a literal hole in space or just a infinite long tube?
Actually, the event horizon of a black hole would be an almost perfect sphere. After all, space has three dimensions (if we disregard time).
Moreover, the area that appears as a black sphere would actually be slightly bigger than the event horizon. Contrary to what Hank says in this video, a black hole isn't black because light can't escape it, but rather because light escaping from slightly outside the event horizon is red-shifted into invisibility.
you could say a behind the event horizon are, as the name suggests, events that did never take place from an outsiders perspective.
cool, where can I download one?
I assume that the "Don't Panic" would be written in large, friendly letters if TH-cam allowed that.
you can escape a black hole, you dont have to reach lightspeed to escape. lets say you have a jetpack that travels at 1 mile a second, earths escape velocity is 7 mps, with constant thrust you can escape at 1 mps (ignoring the atmosphere) the same is with black holes (assuming your not dead) so you CAN escape black holes.
Donut Ten This is false. The geometry of space-time inside a black hole is so warped that no direction actually points out - the rest of the universe is actually stuck in the 'past', and thrusting radially actually makes you reach the singularity _faster_ than not thrusting at all.
There's nothing to escape from in black hole because in a singularity, space itself is warped. You are basically still moving in straight line but you are just riding that curved space so any thrust in movement will only help you go towards singularity.
Good video John Green but still waiting your new book to come out
The graphic shows the earth being 93 million miles from the center of the galaxy. That's actually our distance to the sun.
Like you said at the beginning, we're ~26,000 light years away. Each light year is about 6 trillion miles.
It seems like black holes essentially recycle galaxies matter. They are destructive but they also contribute to a galaxies size and creating new stars and matter.
I wish I was a doggo or something so I wouldn't be able to have the capacity to think about this stuff and have existential crisis's about how insignificant I am in the Universe every time I watch a sci show video about space
Without a black hole, our galaxy wouldn't hold together very well.
TheSonicGod Why not?
It is the consistent gravitational pull that our galaxy circulates around. Without it, everything would be flung into the abyss.
Except that it only weighs about four million solar masses, while the galaxy as a whole has a mass of about one trillion solar masses. Removing one millionth of the mass of the galaxy wouldn't have a noticeable effect on objects that weren't already right next to Sagittarius A*
A question to understand it simply...
Moon revolves around earth.
Earth revolves around sun.
Sun with everything else (solar sys & stars) makes a galaxy which is also revolving around the center of milkyway galaxy with black hole in the center saggitarius A????
Is not the whole disk of our galaxy an accretion disk? Are not the spiral arms just warped gravitationally bound filaments being twisted by what ultimately is frame dragging of the black hole?
No, the frame dragging effect, even for a supermassive black hole is still a tiny, tiny effect. Also, the galaxy is not the accretion disk for the black hole. Even the most massive supermassive black hole is much too small for that. The galaxy is held together by the aggregate mass of the black hole, stars, gas and dark matter of the galaxy.
The spiral arms of spiral galaxies are somewhat mysterious. We don't actually know what forms them. They do not actually correspond 1:1 to the mass distribution. They appear to be more of a travelling pressure wave going around the galaxy which triggers star formation. We see them because that's where bright stars associated with star formation show up. It is not even clear that the arms rotate at the same speed as the galaxy.
I really need your help guys! I am trying to find the mass of the black hole by myself and something is wrong..are you sure that the attraction between 2 humans is 10,000 times more powerful that the attraction betwen me and the black hole? or that was an estimation?
DivineHell666 This sounds fun, so I'm going to do it too (you've probably figured it out by now, and if so sorry, but it does look like fun). Force between two objects F = G m M / r^2.
So F(two humans)/F(black hole) = m(human) r(human-black hole)^2 / r(human-human)^2 M(black hole)
Call a human 100 kg, distance between humans being 1 metre, and the distance to Sagittarius A* is 25 900 LY. This gives us:
F(two humans)/F(black hole) = 6E42 kg / M(black hole)
If the ratio of the forces is really 10 000, then the mass of the black hole must be 6 E38 kg. Looking it up on Wikipedia, we find that its mass is actually 9E36 kg, so the two humans would have to be standing about 5 metres apart. It's a pretty good estimate, though!
Natasha Taylor That's pretty much what I did, it gave me 8.57E36 kg so I estimated right , and I also got an A for it. Thank you though for solving it .