Chandra 'Hears' A Black Hole

"Asimov" wrote in message
I'm still trying to figure out how they get sound to travel in a vacuum!!!

I don't think they're saying that it would reach earth. Just that if you
were in the cosmic gas next to the black hole, you would hear the "sound".

Matthew F Funke replied to Jeff Root:

Middle C has a frequency of 261.63 Hz. The B-flat just below
it has a frequency of 233.08 Hz. An octave is a doubling or
halving of frequency, so 57 octaves below the B-flat just below
middle C is 1.6 e-15 Hz, if I calculated correctly. That is a
period of 618,307,825,964,715 seconds, or 19,592,992 years,
again if I calculated correctly.

A bit generous with our precision, aren't we?

At the time I wrote the message I determined the probability
of anyone commenting on the level of precision to be 41.26% if
Matthew Funke didn't read it, or 76.14% if Matthew Funke did
read it. I gamboled and lost.

Actually, I was parsimonious with my editing rather than
generous with precision. I could have edited the values to
some number of significant digits. That would have required
deciding how many significant digits to retain, and how to
round the least significant digit. I hate making decisions.
So I just truncated the result of the second calculation to
integer seconds, and that of the third to integer years.
I knew that everyone but the registered kooks would
understand, and that the kooks wouldn't be interested.
That left only Matthew Funke to make a comment, just as I
predicted a week from last Wednesday. Zetas left again!

Makes no sense to me.

Well, sound waves are just longitudinal pressure waves
through a medium, yes?

I'll buy that. Is it on audio CD?

In a sense, what this black hole is throwing out could be seen as
such (as the original article stated, "ripples in the gas filling
the cluster")... though a period of 19.6 million years seems to
stretch the idea of "sound" to the breaking point. -=shrug=-

A barrier to my comprehension was that I hadn't bothered to
read the info in the links. One of the articles you just
gave a link to says the sound waves "sweep across hundreds of
thousands of light years." I hadn't imagined that sound could
propagate that far. I was imagining something on the scale of
a solar system. I don't think it would be possible to observe
sound waves with a period of 19.6 million years in a space as
small as a solar system.

The new barrier is incomprehension that sound waves could go
so far and last so long.

-- Jeff, in Minneapolis

..

Well, sound waves are just longitudinal pressure waves through a
medium, yes? In a sense, what this black hole is throwing out could be
seen as such (as the original article stated, "ripples in the gas
filling the cluster")... though a period of 19.6 million years seems to
stretch the idea of "sound" to the breaking point. -=shrug=-

If a black hole made a sound in the universe, and no one could ever
hear it, did it really make a sound....WOW....Deep dude!

I agree though. I think this is NASA's attempt once again to stretch
the truth to get headlines. The latest Astronomy has an interview with
the Professor of Physics at Columibia (if I recall correctly). He
complains of the same thing. I've got five bucks that at my clubs
public star party on Sat I am going to have to explain this to at
least one member of the public who know believes that a black hole is
playing Jimi Hendrix tunes from the other end of the universe. Oh
well, at least it gets science some attention.

Matt

In message , Dean
writes
1. I think that the scientists observed the 30,000 light year ripples,
estimated the velocity of sound in the gas, and deduced the frequency.

I thought this too, but my calculations give a speed around a few
hundred km per second - which is several orders of magnitude above Mach
1, but still hundreds of times slower than c. What assumptions were
they making here?

--
Mike

"Jeff Root" wrote in message om...

. . .
The new barrier is incomprehension that sound waves could go
so far and last so long.

-- Jeff, in Minneapolis

The article does use the "sort of" marks (read the title,
Chandra *sort of* Hears A Black Hole) and mentions
that the frequency is far below what the human ear can
hear.

As for going so far for so long... perhaps we can conclude
that black holes are...

*R*E*A*L*L*Y* *R*E*A*L*L*Y* *L*O*U*D* ...(?)

g

happy days and...
starry starry nights!

--
"Oh give me please the Universe keys
That unlock all those mysteries!"
You pay your fees, you find some keys
That keeps you always groping.

"Oh give me please the Happiness keys
That ease the pain of biting fleas!"
Today you seize you need no keys,
That door is always open.

Paine Ellsworth

In article , Matt
wrote:

Well, sound waves are just longitudinal pressure waves through a
medium, yes? In a sense, what this black hole is throwing out could be
seen as such (as the original article stated, "ripples in the gas
filling the cluster")... though a period of 19.6 million years seems to
stretch the idea of "sound" to the breaking point. -=shrug=-

If a black hole made a sound in the universe, and no one could ever
hear it, did it really make a sound....WOW....Deep dude!

I agree though. I think this is NASA's attempt once again to stretch
the truth to get headlines. The latest Astronomy has an interview with
the Professor of Physics at Columibia (if I recall correctly). He
complains of the same thing. I've got five bucks that at my clubs
public star party on Sat I am going to have to explain this to at
least one member of the public who know believes that a black hole is
playing Jimi Hendrix tunes from the other end of the universe. Oh
well, at least it gets science some attention.

Matt

Wrong. It is getting attention for pseudoscience and every day making
pseudoscience more and more legitmate (in the eyes of the fooled
public). NASA's shameless attempts at headline production by these
'discoveries' do nothing short of dishonoring what science should be
all about.

CC

Wrong. It is getting attention for pseudoscience and every day making
pseudoscience more and more legitmate (in the eyes of the fooled
public). NASA's shameless attempts at headline production by these
'discoveries' do nothing short of dishonoring what science should be
all about.

CC

What do you expect? The agency was at first staffed by White rocket
scientists, and it achieved near-miracles, extending the reach of manned
spaceflight from low earth orbit to the moon. Then NASA became
"bureaucritized." Its successes and the political situation (the US/USSR
competition) made spaceflight a symbol of political and military excellence,
and every politician in Congress wanted to put his finger into NASA's pie.
Of course, things started going wrong.

Then NASA became subject to Equal Opportunity (i.e. Reverse Discrimination)
laws. Blacks began to appear front of the TV cameras as "spokesmen" for any
space missions that were not (so far) having any trouble. During the
televised Mars Pathfinder mission, JPL set some of these porch-monkeys at
stage-center for one of their room monitors. The Blacks knew when their
camera was live: they'd start pointing at this or that, and nodding their
heads sagely, and at least twice, while the broadcast was being fed from a
different camera, one of them was shown crossing the field-of-view carrying
"papers," which presumably were critical papers whose carrying importantly
needed to be done.

So the dog-and-pony sideshowism in which NASA is engaging isn't a new
phenomenon; it's merely a continuation of a bad trend that began in the late
1960s.

Jerry Abbott

"Jerry Abbott" wrote in message
...

What do you expect? The agency was at first staffed by White rocket
scientists, and it achieved near-miracles, extending the reach of manned
spaceflight from low earth orbit to the moon. Then NASA became
"bureaucritized." Its successes and the political situation (the US/USSR
competition) made spaceflight a symbol of political and military
excellence,
and every politician in Congress wanted to put his finger into NASA's pie.
Of course, things started going wrong.

Then NASA became subject to Equal Opportunity (i.e. Reverse
Discrimination)
laws. Blacks began to appear front of the TV cameras as "spokesmen" for
any
space missions that were not (so far) having any trouble. During the
televised Mars Pathfinder mission, JPL set some of these porch-monkeys at
stage-center for one of their room monitors. The Blacks knew when their
camera was live: they'd start pointing at this or that, and nodding their
heads sagely, and at least twice, while the broadcast was being fed from a
different camera, one of them was shown crossing the field-of-view
carrying
"papers," which presumably were critical papers whose carrying importantly
needed to be done.

So the dog-and-pony sideshowism in which NASA is engaging isn't a new
phenomenon; it's merely a continuation of a bad trend that began in the
late
1960s.

Jerry Abbott



So Jerry... How long have you been a KKK member?

What do you expect? The agency was at first staffed by White rocket
scientists, and it achieved near-miracles, extending the reach of manned
spaceflight from low earth orbit to the moon. Then NASA became
"bureaucritized." Its successes and the political situation (the
US/USSR
competition) made spaceflight a symbol of political and military
excellence,
and every politician in Congress wanted to put his finger into NASA's
pie.
Of course, things started going wrong.

Then NASA became subject to Equal Opportunity (i.e. Reverse
Discrimination)
laws. Blacks began to appear front of the TV cameras as "spokesmen" for
any
space missions that were not (so far) having any trouble. During the
televised Mars Pathfinder mission, JPL set some of these porch-monkeys
at
stage-center for one of their room monitors. The Blacks knew when their
camera was live: they'd start pointing at this or that, and nodding
their
heads sagely, and at least twice, while the broadcast was being fed from
a
different camera, one of them was shown crossing the field-of-view
carrying
"papers," which presumably were critical papers whose carrying
importantly
needed to be done.

So the dog-and-pony sideshowism in which NASA is engaging isn't a new
phenomenon; it's merely a continuation of a bad trend that began in the
late
1960s.

Jerry Abbott



So Jerry... How long have you been a KKK member?

I never had membership in the KKK. I worked for the National Alliance for
five years, but now I'm back into freelance racial activism.

One of my projects is the creation of a celestial mechanics tutorial
website, whose beginning you can find at

http://www.jabpage.org/posts/transca.html
(under construction)

Jerry Abbott