View previous topic :: View next topic |
Author |
Message |
Steve Iannetti GweiLo
Joined: 24 Jan 2002 Posts: 697
|
|
Back to top |
|
|
MIKE BURN Generally Crazy Guy
Joined: 08 Nov 2001 Posts: 4825 Location: Frankfurt / Europe
|
Posted: Wed Sep 10, 2003 8:26 pm Post subject: Big black holes sing bass |
|
|
Quote: WASHINGTON, Sept 9 (Reuters) -- Big black holes sing bass. One particularly monstrous black hole has probably been humming B flat for billions of years, but at a pitch no human could hear, let alone sing, astronomers said this week.
"The intensity of the sound is comparable to human speech," said Andrew Fabian of the Institute of Astronomy at Cambridge, England. But the pitch of the sound is about 57 octaves below middle C, roughly the middle of a standard piano keyboard.
This is far, far deeper than humans can hear, the researchers said, and they believe it is the deepest note ever detected in the universe.
The sound waves are emanating from the Perseus Cluster, a giant clump of galaxies some 250 million light-years from Earth. A light-year is about 6 trillion miles (10 trillion km), the distance light travels in a year.
Fabian and his colleagues used NASA's orbiting Chandra X-Ray Observatory to investigate X-rays coming from the cluster's heart.
Researchers presumed that a supermassive black hole, with perhaps 2.5 billion times the mass of our sun, lay there, and the activity around the center bolstered this assumption.
Black holes are powerful matter-sucking drains in space, and astronomers believe most galaxies, including our own Milky Way, may contain black holes at their centers.
Black holes have not been directly observed, because their gravitational pull is so strong that nothing, not even light, can escape it.
Making waves
So researchers have concentrated on what happens around the edges of black holes, just before matter is pulled in.
When scientists trained the Chandra observatory on the center of Perseus last year, they saw concentric ripples in the cosmic gas that fills the space between the galaxies in the cluster.
"We're dealing with enormous scales here," Fabian said in a telephone interview. "The size of these ripples is 30,000 light-years."
Fabian said the ripples were caused by the rhythmic squeezing and heating of the cosmic gas by the intense gravitational pressure of the jumble of galaxies packed together in the cluster.
As the black hole pulls material in, he said, it also creates jets of material shooting out above and below it, and it is these powerful jets that create the pressure that creates the sound waves.
To scientists, he said, pressure ripples equate to sound waves. By calculating how far apart the ripples were, and how fast sound might travel there, the team of researchers determined the musical note of the sound.
MIKE
|
|
Back to top |
|
|
Yj2
Joined: 25 Jan 2002 Posts: 340 Location: Frankfurt / Germany
|
|
Back to top |
|
|
LyinDanTheManagerMan
Joined: 03 Sep 2002 Posts: 39
|
Posted: Fri Sep 12, 2003 4:24 am Post subject: Well |
|
|
That's a mighty tenuous premise, calling those wavs "sound". I don't hear anything. Must be the vacuum in between.
|
|
Back to top |
|
|
markhewer
Joined: 04 Jan 2003 Posts: 246
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
Blocked registrations / posts: 152258 / 0
|