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The Sound of a Black Hole
Snags writes "Astronomers have used the Chandra X-ray Observatory to observe the deepest, lowest-frequency sound waves ever observed. By my calculations, the 'B-Flat 57 octaves below middle-C' has a period of 9.8 million years. Despite arguments that explosions in space movies should be silent, it is legitimate to call these sound waves because at that frequency, particles of space dust can 'see' each other through gravity. These notes are 'over a million billion times deeper than the limits of human hearing', so to call it infra-sound would be a bit of an understatement."
Infrasound! Now that explains why many people have this irrational fear of black holes! :-)
I suffer from attention surplus disorder.
When I read "The Sound of a Black Hole"
the sound I heard in my mind was "oh shit there's a black hole!"
Infrasound is a sound wave. Black hole infra radiation is not sound at all. It is x-ray...
Code poet, espresso fiend, starter upper.
So this is a 639 year concert that has started in Germany. The concert has been ongoing for 17 months (the initial "quiet period" of the organ filling) however the first three note chord has been hit.
Boy wish I had that kind of time to waste... Imagine the monks 630 years from now going - "Well, this is over now - what the hell are we going to do now ?"
I have mod points and I am not afraid to use them
They're not saying that infra-radiation is sound--they used the telescope to see ripples in the gas. That's the sound.
AKA "a giant sucking sound."
B-Flat 57 octaves below middle-C, and it's the sound of a black hole. My , they've discovered the brown note!
Umm, sorry for that...
My extreme audiophile friend now has to replace his whole system to capture the experience of these new sounds.
__ Someday, but not this morning, I'll finally learn to use the preview button.
Sound is the word defining that which the ears hear. Is it possible to listen, directly, to that shock wave even if one were standing (floating) in the midst of it? If not, it ain't sound.
Why is everything good always in B-flat? The only good B-sharp ever was a Simpsons episode: Homer's Barbershop Quartet. Ah, a classic. Now, where can I find Homer at the Bat?
And now, for a sig that's a complete copout.
In space no once can hear you hum...
.sdrawkcab si gis siht
"These sound waves are thought to have been produced by explosive events occurring around a supermassive black hole (bright white spot) in Perseus A, the huge galaxy at the center of the cluster. The pitch of the sound waves translates into the note of B flat, 57 octaves below middle-C. This frequency is over a million billion times deeper than the limits of human hearing, so the sound is much too deep to be heard."
A blog like any other.
I wouldn't buy tickets to a music-playing blackhole concert. They suck.
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Roses are #FF0000, Violets are #0000FF, find / -name '*base*' |xargs chown -R us && mv zig greatjustice
Seems that Satchmo (Louis Armstrong) found his soul home. Of course, there have been other infra-bass singers, too. PRE
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
Seems that Satchmo (Louis Armstrong found his 'soul home' among the stars... PRE
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
Who have they convinced to sit there holding down the keys for the chord for the next 1.9 years???
A little planning goes a long way...
play the "brown note" ?
I'm on the team that did this. Ask any questions you like!
In other words: in space, nobody can hear you scream... but they can hear you fart
Black holes rely on an assumption that gravity has no limits on its strength, and to some extent on it following a strict Newtonian curve.
Thinking of "curves" in space-time is an interesting analogy for gravity, but still doesn't address the mechanism - sure, the planet may be on a "45 degree" incline in spacetime, but what forces it down... and not up? You would nearly have to posit the existence of some constant stream of gravitons coming at 'right angles' to three-dimensional space in order to actually push things 'down the well'.
There are alternate corpuscular (i.e. caused by particles; "quantum") models of the mechanism of gravity. There's the LeSagian model, with modern reworks that range from the bizarre-yet-possible theories of Tom Van Flandern, to the more "moderate" theories of Paul Stowe explaining how the "drag" factor that detractors expect doesn't show up, in exactly the sort of way that Feynman expressed it for electromagnetism.
The LeSage-type theories are, in general, "push" theories, which operate in a medium filled with gravitons (just as space is filled with photons) that are deflected/absorbed near bodies and cast 'shadows' that create a low "pressure" area close to surfaces and, to a lesser extent, between bodies.
The formulae calculate out approximately to Newton's/GR's gravity equation, but with some interesting exceptions:
This upper limit on the strength of gravity may prevent the ultimate collapse that black hole theory requires.
Black holes are still a theoretical construct. Even the jets, now often taken as a 'sign' of a black hole, are still a largely unexplained phenomenon, one that is also associated with accretion disks for newly-forming stars.
So if something's singing in that cloud, it may not be as dense as it's accused of being.
I apologize for all the jargon. I shall go read another thread on SCO as just punishment :)
Binary geeks can count to 1,023 on their fingers
... was identical to that sound Anna Nicole makes when eating spagetti.
(Badum-bum *crash*)
Thank you, thank you. I'll be here all week.
Please remember to tip your waiters.
I think it comes in useful when dealing with instruments whose key is not C. It makes transposing the key easier. In the final form, I guess they would be converted to the "actual" notes.
main(O){10<putchar((O--,102-((O&4)*16| (31&60>>5*(O&3)))))&&main(2+ O);}
LN2 is cool!
That's right. We see the ripples as X-ray emission is very sensitive to gas density (goes like density squared), so we see the dense regions where the gas is being compressed by the sound wave. The picture is a "snapshot" as we never see the wave move.
Is this the Brown Note. Is it real?
I wonder what the energy associated with these sound waves are. It's got to be rather sizeable, right? I'm too far out of college to remember all my energy equations but still retaining enough to be curious.
In a simplistic level, think of a stereo's tweeter speaker...short soundwaves that just hurt the ears if turned up too high. Then you've got the bass...longer soundwaves that you can feel the "punch". So I wonder what these soundwaves from the black holes are capable of doing. They've got to have some sort of impact on moving objects in space. Anyone care to explain any more about this?
"He uses statistics as a drunken man uses lampposts...for support rather than illumination." - Andrew Lang
Make that 10^36 Joules per s
Check chandra images:
m l
http://chandra.harvard.edu/photo/chronological.ht
Thanks for the Harvard link! Here are some more images from Space.com. This one is a composite photo. of the images picked up by the various types of telescopes.
Does anyone know if there is a sound card under $50 that can record these black hole sounds? Can I just use the "line-in" on my puter? Should I encode them to WMA? Thanks!
The period of the wave is 9.6 million years. A quick calculation (haven't checked my sums) suggests the frequency is about 3.3 x 10^-15 Hz (or 0.0000000000000033 Hz)
Maybe the chills and sensations we feel that we assume are ghosts, are the interferance patterns from many blackhole wavefronts?
Dont ask me, im just the bass player!
...if a tree falls in the woods and no one is around to hear it, it dosn't make a sound since sound implies someone heard it.
I suppose it fillows that there is no such thing as ultrasound and the images I have of my daughter in utero were fradulent.
Sound is periodic vibrations due to compression waves in a medium. Within a certain range of frequencies, sound can be heard (if it is loud enough) outside of those frequencies, we still call it sound even if no one can hear it. That's what we're talking about here.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
If you were in a black hole, you'd B Flat too!
Or . . . . Infrastatement?
I don't know too much about the physics of gravity (yet), at least mathematically, beyond F=Gm1m2/d^2. However, my interpretation of general relativity was that a collection of mass (or energy) moves inertially through spacetime, that is, without inherent acceleration, and the acceleration we see occurs because the object is following the topology of space as it goes along. If spacetime is curved, the shortest distance between two points is some sort of curve.
That's why I think the term "gravity well" is particularly illuminating; energy/mass moves inertially through curved space time until it finds its way into a state of equilibrium, the highest local curvature of space possible, just as if a marble in a well is going to stay at the bottom. It also explains a little why an object at the midpoint between two equal masses (assume no other mass around) is in unstable equilibrium: imagine a marble on the very tip of a hill in this case.
Gravity resists integration with the other 3 fundamental forces, and maybe this is because it is not a *force*. Perhaps there really is no gravitic force carrier... Curved spacetime is simply a more elegant concept.
~Demosthenes
WHEN I SHOT HIM