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> the 225-solar-mass black hole was created by the coalescence of black holes each approximately 100 and 140 times the mass of the Sun. Does this mean that 15

> the 225-solar-mass black hole was created by the coalescence of black holes each approximately 100 and 140 times the mass of the Sun. Does this mean that 15 solar masses were converted into energy? Because that's a LOT of energy.

andrepd 1y ago
Yes! And still, gravity is so weak that that immense amount of energy translates to just a relative contraction of less than 10^-20, or about a hair's width in the distance from the Earth to the Moon.
- cgdl 1y ago
  Do we know how far this event was from earth? Wouldn't that distance be the determiner of what the relative contraction observed on earth would be?
  - sgustard 1y ago
    estimated distance of 2.2 Gpc per https://en.wikipedia.org/wiki/GW231123 https://en.wikipedia.org/wiki/GW231123
    - irjustin 1y ago
      That's how fast the millennium falcon goes
    - BurningFrog 1y ago
      That's 7.2 billion light years. More than halfway to the most distant galaxy the Webb telescope has found. So this event happened 7.2 billion years ago. There is no mention of in which direction. Maybe the triangulation wasn't working at the time. You need three LIGOs for that.
- UltraSane 1y ago
  At 10 times the Schwarzschild radius Space literally stretches and contracts by 10-100%
- ssl232 1y ago
  This is because space is _stiff_. Recall Hooke’s law from high school physics. The k constant represents the stiffness of the object. A rubber band is about 50. A sky scraper, about a million. Space? About 10^46 if I recall correctly. So it takes a truly enormous amount of energy in the form of gravitational waves to be able to move space enough for it to be detectable on Earth. And the only objects that can do that are the most massive ones moving at close to the speed of light: black holes, neutron stars, supernovae (the latter would have to be very close for us to see gravitational waves from - close enough that we’d likely see it with the naked eye as well).
- misja111 1y ago
  Sure but we are 7 billion lightyears away from the source of the waves. Imagine if we'd be a bit closer ..
UltraSane 1y ago
Yes. Black hole mergers are the highest energy events in the universe in terms of watts.
aaronharnly 1y ago
Let’s see — the Tsar Bomba nuclear weapon released the equivalent of converting about 2.3 kg of matter into energy (1). One solar mass is about 2 x 10^30 kg, so round numbers this event released the same as 10^31 Tsar Bombas, which is … a lot of energy? That number is too big to be a good intuition pump. Let’s try again: over the course of its entire lifetime of about 10 billion years, the sun will release about 0.034% of its mass as energy (2). So one solar mass of energy is about 3000 solar-lifetime-outputs. So this event has released about as much energy as 45,000 suns over their entire lifetime. I’m not sure how much of the energy was released in the final few seconds of merger, but probably most of it? So… that’s a lot of energy. (1) https://faculty.etsu.edu/gardnerr/einstein/e_mc2.htm https://faculty.etsu.edu/gardnerr/einstein/e_mc2.htm (2) https://solar-center.stanford.edu/FAQ/Qshrink.html https://solar-center.stanford.edu/FAQ/Qshrink.html
- vjvjvjvjghv 1y ago
  I have read somewhere that an experiencing a supernova at sun distance would be the same as holding a hydrogen bomb to your eyeball. The energy released in these events is basically unimaginable.
  - aaronharnly 1y ago
    Probably here: https://what-if.xkcd.com/73/ https://what-if.xkcd.com/73/ And it’s even more astonishing — the supernova at 1 AU would be the same as a billion hydrogen bombs at your eyeball.
    - mytailorisrich 1y ago
      Another way to look at it is that a hydrogen bomb is very small at planetary scale and so microscopically small at any astronomical scale.
      - aaronharnly 1y ago
        I appreciate this point – it would take quite a few Tsar Bombas to approach the binding energy of a planet.
hansulu 1y ago
I was disappointed to learn that it would require billions of solar masses of energy from a black hole merger to be able to ride the gravitational wave starting at a distance of a few Schwarzschild radii. It seems like riding a plasma jet might be better. (Just planning my next trip.)
- pixl97 1y ago
  Much better off just chucking 90% of your mass into the blackhole to get a hella kick.
tashmahalic 1y ago
Into what form of energy is that mass converted?
- BurningFrog 1y ago
  Maybe all of it is gravitational waves? I don't think much else would escape the black hole environment.
  - misja111 1y ago
    Kinetic energy is another option
  - jajko 1y ago
    Need a bit of oomph to move the very fabric of this universe a bit. But energy conversation laws say its just then spread all over the place across time, just like ripples in pond, suspended into nothingness of its own little universe... or something Tells me a bit darker thing in between the lines - the chance some advanced civilization (or us in far future if we actually survive) traveling FTL by bending space massively is next to zero, we would see (or detect soon) the evidence... unless they do it on planck-level of precision and self-contain all ripples. Nah, it really seems c is the ultimate barrier so far... depressing.
    - mr_toad 1y ago
      > Need a bit of oomph to move the very fabric of this universe a bit. It’s enough “oomph” that we can detect it more than half way across the universe.
- csomar 1y ago
  Pure energy.
doikor 1y ago
Can some of the mass escape as gas/mass flying out into space? Basically is energy the only way for mass to exit such an event?
- Thiez 1y ago
  No mass escapes. It is purely gravitational waves that are emitted. There is no sneak peek behind the event horizon curtain during a black-hole merger.
veunes 1y ago
It's hard to wrap your head around, but that's more energy than all the stars in the observable universe combined put out during that instant
richardw 1y ago
Converted into energy and then escape the black hole, from which light can’t escape? That doesn’t seem to compute. And if it’s converted into gravity waves then we have an excellent obvious candidate for how most energy will escape a black hole. It won’t be waiting around for hawking radiation.
- dd_xplore 1y ago
  I think during the merger the event horizon must be changing rapidly, so I guess there's some(or a lot) of chance that matter can escape these merger events. The matter will already have high kinetic energy...

andrepd 1y ago

Yes! And still, gravity is so weak that that immense amount of energy translates to just a relative contraction of less than 10^-20, or about a hair's width in the distance from the Earth to the Moon.

cgdl 1y ago
Do we know how far this event was from earth? Wouldn't that distance be the determiner of what the relative contraction observed on earth would be?
- sgustard 1y ago
  estimated distance of 2.2 Gpc per https://en.wikipedia.org/wiki/GW231123 https://en.wikipedia.org/wiki/GW231123
  - irjustin 1y ago
    That's how fast the millennium falcon goes
  - BurningFrog 1y ago
    That's 7.2 billion light years. More than halfway to the most distant galaxy the Webb telescope has found. So this event happened 7.2 billion years ago. There is no mention of in which direction. Maybe the triangulation wasn't working at the time. You need three LIGOs for that.
UltraSane 1y ago
At 10 times the Schwarzschild radius Space literally stretches and contracts by 10-100%
ssl232 1y ago
This is because space is _stiff_. Recall Hooke’s law from high school physics. The k constant represents the stiffness of the object. A rubber band is about 50. A sky scraper, about a million. Space? About 10^46 if I recall correctly. So it takes a truly enormous amount of energy in the form of gravitational waves to be able to move space enough for it to be detectable on Earth. And the only objects that can do that are the most massive ones moving at close to the speed of light: black holes, neutron stars, supernovae (the latter would have to be very close for us to see gravitational waves from - close enough that we’d likely see it with the naked eye as well).
misja111 1y ago
Sure but we are 7 billion lightyears away from the source of the waves. Imagine if we'd be a bit closer ..

UltraSane 1y ago

Yes. Black hole mergers are the highest energy events in the universe in terms of watts.

aaronharnly 1y ago

Let’s see — the Tsar Bomba nuclear weapon released the equivalent of converting about 2.3 kg of matter into energy (1). One solar mass is about 2 x 10^30 kg, so round numbers this event released the same as 10^31 Tsar Bombas, which is … a lot of energy? That number is too big to be a good intuition pump. Let’s try again: over the course of its entire lifetime of about 10 billion years, the sun will release about 0.034% of its mass as energy (2). So one solar mass of energy is about 3000 solar-lifetime-outputs. So this event has released about as much energy as 45,000 suns over their entire lifetime. I’m not sure how much of the energy was released in the final few seconds of merger, but probably most of it? So… that’s a lot of energy. (1) https://faculty.etsu.edu/gardnerr/einstein/e_mc2.htm https://faculty.etsu.edu/gardnerr/einstein/e_mc2.htm (2) https://solar-center.stanford.edu/FAQ/Qshrink.html https://solar-center.stanford.edu/FAQ/Qshrink.html

vjvjvjvjghv 1y ago
I have read somewhere that an experiencing a supernova at sun distance would be the same as holding a hydrogen bomb to your eyeball. The energy released in these events is basically unimaginable.
- aaronharnly 1y ago
  Probably here: https://what-if.xkcd.com/73/ https://what-if.xkcd.com/73/ And it’s even more astonishing — the supernova at 1 AU would be the same as a billion hydrogen bombs at your eyeball.
  - mytailorisrich 1y ago
    Another way to look at it is that a hydrogen bomb is very small at planetary scale and so microscopically small at any astronomical scale.
    - aaronharnly 1y ago
      I appreciate this point – it would take quite a few Tsar Bombas to approach the binding energy of a planet.

hansulu 1y ago

I was disappointed to learn that it would require billions of solar masses of energy from a black hole merger to be able to ride the gravitational wave starting at a distance of a few Schwarzschild radii. It seems like riding a plasma jet might be better. (Just planning my next trip.)

pixl97 1y ago
Much better off just chucking 90% of your mass into the blackhole to get a hella kick.

tashmahalic 1y ago

Into what form of energy is that mass converted?

BurningFrog 1y ago
Maybe all of it is gravitational waves? I don't think much else would escape the black hole environment.
- misja111 1y ago
  Kinetic energy is another option
- jajko 1y ago
  Need a bit of oomph to move the very fabric of this universe a bit. But energy conversation laws say its just then spread all over the place across time, just like ripples in pond, suspended into nothingness of its own little universe... or something Tells me a bit darker thing in between the lines - the chance some advanced civilization (or us in far future if we actually survive) traveling FTL by bending space massively is next to zero, we would see (or detect soon) the evidence... unless they do it on planck-level of precision and self-contain all ripples. Nah, it really seems c is the ultimate barrier so far... depressing.
  - mr_toad 1y ago
    > Need a bit of oomph to move the very fabric of this universe a bit. It’s enough “oomph” that we can detect it more than half way across the universe.
csomar 1y ago
Pure energy.

doikor 1y ago

Can some of the mass escape as gas/mass flying out into space? Basically is energy the only way for mass to exit such an event?

Thiez 1y ago
No mass escapes. It is purely gravitational waves that are emitted. There is no sneak peek behind the event horizon curtain during a black-hole merger.

veunes 1y ago

It's hard to wrap your head around, but that's more energy than all the stars in the observable universe combined put out during that instant

richardw 1y ago

Converted into energy and then escape the black hole, from which light can’t escape? That doesn’t seem to compute. And if it’s converted into gravity waves then we have an excellent obvious candidate for how most energy will escape a black hole. It won’t be waiting around for hawking radiation.

dd_xplore 1y ago
I think during the merger the event horizon must be changing rapidly, so I guess there's some(or a lot) of chance that matter can escape these merger events. The matter will already have high kinetic energy...