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#101 2004-12-15 03:53:52

chat
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From: Ontario Canada
Registered: 2003-10-23
Posts: 371

Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

ecrasez_l_infame,

Don't worry because it confuses me to no end that the only consistent thing in the universe is nothing.
And that doesn't even last forever *lol*

It's comforting to think that nothing might exist somewhere.
Good fun to think about though. smile


The universe isn't being pushed apart faster.
It is being pulled faster towards the clumpy edge.

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#102 2004-12-18 21:48:28

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.spaceref.com/news/viewpr.htm … 2]Launched in Antarctica

*Errrr...I was so tempted to create a separate thread for this.  But no, will post it here.  Is the first I've heard of it.  Wow. 

Question:  If (and yes, I understand this is all theoretical) there were equal amounts of matter and antimatter created as a result of the Big Bang, how did matter gain dominance?  How could an equal half of something be more?  ???

The team seeks to understand the origin of cosmic antimatter and to find evidence for the existence of Hawking radiation from "evaporating" black holes, a theory proposed by Prof. Stephen Hawking

The instrument, called BESS-Polar, launched successfully on December 13 from McMurdo Station, Antarctica, beneath a 40-million-cubic-foot scientific balloon, as big as a football field. To maximize the possibility of finding the antimatter predicted by Hawking, the team is hoping for at least a 10-day flight, or once around the South Pole, in a near-space environment above 99% of the atmosphere. The instrument is now circling the Pole at an average altitude of 24 miles

"The northern and southern polar regions are the best places to collect low-energy antiprotons"..."The Earth's magnetic field protects us from antiprotons and other cosmic-ray particles from space. The magnetic field funnels charged particles toward the Earth's poles, so the concentration of lower-energy cosmic rays entering into the Earth's atmosphere there is greater."

*And "primordial microscopic black holes"??!  Okaaaaaay.  :hm: 

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#103 2004-12-19 06:27:38

chat
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

ecrasez_l_infame,

4 simple solutions come to mind for this problem.

1. antimatter was concentrated at higher locations in the black hole , so in the initial big bang explosion most of the antimatter never got the chance to react with matter.
It still exists at the edge of the universe.

2. antimatter isn't in equal amounts with matter.
The antimatter that was created is nearly all gone now, antimatter is somehow converted to a form that turns a % into matter in the black hole explosion.

3. matter and its products can react with more  than 1 antimatter atom.

4.The big bang was like a nova explosion.
Only a % of the big bang matter was ejected in the initial big bang.
Most of the antimatter is still inside the primordial black hole, and antimatter is heavier than matter.

#4 is my favorite, if it exists finding the giant big bang black hole that may still exist in the center of the universe shouldn't be to hard with starlight refraction.


The universe isn't being pushed apart faster.
It is being pulled faster towards the clumpy edge.

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#104 2004-12-21 11:49:40

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

*Thanks for your input, Chat.

And "primordial microscopic black holes"??!  Okaaaaaay.  :hm: 

--Cindy

The previous article's mention of microscopic black holes got me curious.  I read every article on BH's I come across and don't recall a reference to them previously.  As luck would have it, I found an informative and fantastic article on my first Google attempt:

http://www.usatoday.com/news/science/as … icroscopic black holes could be forming regularly

They're just as dense as "regular" black holes, i.e. light can't escape from them either.  They disappear quickly and haven't yet been "seen." 

Anticipation is that hundreds of microscopic BH's might be detected within the next 5 years.  MBH's are estimated to be "10 billionths of a billionth of an inch" in diameter, decay instantly, "showering the sky with a cornucopia of oddball physics particles."  We're assured that MBH's are harmless to us, etc., even if they "may be forming regularly right over our heads."

Really cool to consider:

On top of that, spotting many black holes would bolster fashionable theories that explain gravity by suggesting that other dimensions — beyond familiar ones such as height, depth and time — exist "curled up" and hidden in the universe.

Article indicates reluctance on the part of some physicists to consider extra dimensions.

--Cindy

::EDIT::  Wanted to highlight this as well:

Shapere and Feng hypothesize that cosmic rays, high-energy particles traveling at near the speed of light throughout space, might occasionally smack into tiny particles in Earth's atmosphere squarely enough to compact them into miniature black holes.

*Also mentions the MBH's might be "quite hot."


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#105 2004-12-26 17:45:12

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://antwrp.gsfc.nasa.gov/apod/ap030601.html]GRO J1655-40:  Evidence for a Spinning Black Hole

*From Astropix.  Mentions the "flickering" rate of gas surrounding this beast -- 450 times per second.  Apparently the "flickering" is explained by the rapid rotation of this BH.  Cool image too; looks like you might just fall in head-long (yipes).

-*-

http://antwrp.gsfc.nasa.gov/apod/ap030612.html]Cygnus X-1:  Milky Way's most famous BH

*Further proof Astropix shuffles its Archive; I wouldn't have missed this last year and would likely remember it.  No apparent supernova explosion preceeded the formation of this BH -- because there is no evidence of a "kick" and resultant alteration of course as compared to the other members of its progenitor's star cluster.  Mentions dark gamma-ray bursts.  Hmmm...I'll have to click that link.   :;):  (::edit::  That link unfortunately leads to this message:  "Sorry, but the document you requested is not available on this server"  <frown>  ::end edit::).

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#106 2004-12-26 21:50:57

SpaceNut
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

Yup quick search of Astronomers Find First Direct Evidence Linking Black Holes and Supernovae as you noted. I recall some time ago reading an article that detailed how I think one of the first Black holes was found because the companion star was having its gas stolen from it. The name was very similar... Not all to many light years from here if I recall.. But it escapes me at this time, it was many years ago and may have pre-dated even hubble just not sure any more..

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#107 2004-12-28 14:48:38

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://antwrp.gsfc.nasa.gov/apod/ap020908.html]If you got too close...

*...another interesting item about black holes courtesy of Astropix. 

In fact, near the black hole, you can see the whole sky - light from every direction is bent around and comes back to you.

Wild.   :;):

I'd be very interested to know if they ever confirm the existence of black holes at the center of globular clusters.  Methinks these critters be a-lurking everywhere.  :-\  <chuckle>

--Cindy

::EDIT::  http://antwrp.gsfc.nasa.gov/apod/ap991219.html]Speaking of black holes and binaries 

In a binary system, the higher mass star will evolve faster and will eventually become a compact object - either a white dwarf star, a neutron star, or black hole.

*Have been familiar with the white dwarf star and neutron star possibilities in the past, as binaries go.

::EDIT 2::  And going back to the globular cluster possibility for a second:  It seems generally assumed that GC's are held together by the combined gravitational pull of its stars.  But wouldn't a black hole at the center -- serving as a gravitational anchor of sorts (ala supermassive black holes at the cores of galaxies seeming to anchor the galaxy) -- be a better explanation as to how GC's remain intact and compact?


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#108 2005-01-05 18:30:44

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://story.news.yahoo.com/news?tmpl=s … bles]Black Holes & Bubbles

*BH's more influential in cosmic matters than previously considered?  Are speculating that some BH's prevent hot gas from cooling and thereby stifling star birth.

The one featured in the article is also a tremendous glutton:

"I was stunned to find that a mass of about 300 million Suns was swallowed," said lead researcher Brian McNamara of Ohio University. "This is almost as massive as the supermassive black hole that swallowed it."

The outburst is orchestrated by a supermassive black hole that anchors a distant galaxy sitting amid a tight cluster of galaxies. The black hole has blown two huge bubbles into the galaxy, shoving aside a colossal amount of gas equal to the mass of a trillion Suns, or more than all the stars of our own Milky Way Galaxy.

Each bubble is many times bigger than those seen in previous studies.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#109 2005-01-05 23:50:50

MarsDog
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From: vancouver canada
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Posts: 852

Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.ieee.sjce.net/interface.htm]But perhaps the most fascinating thing about the physical existence of black holes is that, even though the concept of black holes came into existence because of Einstein's theory of relativity, he dismissed them just as another mathematical curiosity.

http://arxiv.org/abs/hep-th/9610135]Dirty Black Holes and Hairy Black Holes

The angular momentum and electric charge indicate structure within the "Black Hole" Not all the mass is at a singularity point. So gravity at the center could be zero ?? Charge repelling and not concentrated at center also ? Could a black hole dweller send us a message, influence the charge distribution inside the black hole, via radio transmission ?

http://relativity.livingreviews.org/Art … .2]Colored Black Holes ??

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#110 2005-01-06 09:10:33

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.ieee.sjce.net/interface.htm]But perhaps the most fascinating thing about the physical existence of black holes is that, even though the concept of black holes came into existence because of Einstein's theory of relativity, he dismissed them just as another mathematical curiosity.

http://relativity.livingreviews.org/Art … .2]Colored Black Holes ??

*Relative (pardon the pun) to the first link MarsDog provided (thank you):

According to Einstein, the speed of a clock depends on where it is and how fast it is moving. Thus if the clock under study ran slowly compared to the cosmic clock,

*What is the cosmic clock (as distinguished from a regular clock)?  Apparently regular clocks can run faster or slower depending on gravitational differences, but I'm wondering about that -cosmic- clock.  What is its standard of measurement and etc.?

Theorists speculate that exotic stuff of this kind did exist in the early universe, but even if such material still existed, the mass needed in order to make a wormhole wide enough to be comfortably traversed by a human would be 10,000 times that of the Sun!

*Interesting.  smile 

-*- -*- -*-

As for the other link I quoted, there's http://antwrp.gsfc.nasa.gov/apod/ap010119.html]this item from Astropix.  Black holes are black because they have an event horizon.  If there are "colored" black holes (seems a contradiction in terms; it's either black or of a different color, right?) -- let's just say "colored gravity wells" instead, in place of "black holes" -- do they have event horizons too?  Or no?

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#111 2005-01-06 11:28:48

MarsDog
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

*What is the cosmic clock (as distinguished from a regular clock)?  Apparently regular clocks can run faster or slower depending on gravitational differences, but I'm wondering about that -cosmic- clock.  What is its standard of measurement and etc.?

http://www.btinternet.com/~time.lord/Relativity.html] since velocity is only relative
and either of the clocks can be regarded as the moving one

Where to put the standard clock ?

========================================

Black holes are not singularities, they have internal structure.
If you were at the center of a large black hole, would gravity  cancel out, allowing normal processes ? The pressure might crush you, as in the center of the Earth,
but you could spin the black hole to form a disk structure ?

========================================

http://www.space.com/scienceastronomy/w … tml]Mother of all Black Holes ?

"It is natural to wonder if there is a connection between the mass that disappears into black hole singularities and the mass that emerges from white hole singularities."

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#112 2005-01-11 07:10:34

SpaceNut
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#113 2005-01-11 08:08:18

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://chandra.harvard.edu/press/05_rel … ml]Chandra Finds Evidence for Swarm of Black Holes Near the Galactic Center

*Yep.  Now for a few comments on the news itself (I read the universetoday.com article, and quoted a portion of it below):

The study involves Sag A*, which is the Milky Way's supermassive black hole.  Chandra studies indicate there are more than 10,000 -- perhaps even 20,000 -- black holes swarming around Sag A*. 

It's speculated that these black holes migrated towards Sag A* over the course of a few billion years and mentions the process of "dynamical friction"; the effect of this is pushing low-mass stars away and towards the galaxy's outskirts.

Neutron stars also collecting there, apparently:

Although the region around Sgr A* is crowded with stars, we expected that there was only a 20 percent chance that we would find even one X-ray binary within a three-light-year radius," said Muno. "The observed high concentration of these sources implies that a huge number of black holes and neutron stars have gathered in the center of the Galaxy."

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#114 2005-01-11 08:59:47

SpaceNut
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

So it looks like gravity wins and that in some areas of space a total collaspe would be expended at the end. Maybe we will some day witness the next big bang and birth of a new universe.

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#115 2005-01-11 12:05:57

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

*Particularly interesting.  Study of Minkowski's Object in galaxy NGC 541, which is approximately half the size of our Milky Way and and 216 million ly distant. 

"Some 20 years ago this kind of thinking was thought to be science fiction," said van Breugel, who along with Croft works at the Laboratory's Institute for Geophysics and Planetary Physics. "It brings poetic justice to black holes because we think of them as sucking things in, but we've shown that when a jet emits from a black hole, it can bring new life by collapsing clouds and creating new stars."

Mentions the interstellar medium and how a radio jet from a black hole in NGC 541 ran into a "hot dense hydrogen medium" which cooled it down, which in turn formed a big neutral hydrogen cloud, which then set off star formation...cosmic dominoes. 

Radio jets are formed when material falls into massive black holes. Magnetic fields around the black holes accelerate electrons to almost the speed of light. These electrons are then propelled out in narrow jets and radiate at radio frequencies because of their motion in the magnetic fields. The jets may affect the formation of stars when they collide with dense gas.

They repeat the information I saw in that Discovery Channel documentary, i.e. massive (or supermassive) black holes are critical in forming new galaxies.

Nice to see a bit of the puzzle more clearly.  Yeah, just a drop in the ocean I know, but heck...info moves so much faster today than it did 25 years ago!  How well I recall waiting for the monthly issue of "Sky and Telescope," and hoping to catch the occasional television report as a kid.  :-\  We're so spoiled by the wonderful, rapid influx of information.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#116 2005-01-12 15:59:39

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

Whats]http://www.space.com/imageoftheday/image_of_day_050112.html]What's special about this galaxy?

*Besides its impressive beauty, this:  "Unlike other spiral galaxies, including our own Milky Way, NGC 1300 is not presently known to have a massive central black hole."

That's especially interesting because the current theory sure seems to tip in favor of -all- galaxies possessing a supermassive or massive black hole at its core, which serves as a gravitational anchor of sorts.

Heres]http://antwrp.gsfc.nasa.gov/apod/ap050112.html]Here's the Astropix offering:  Bigger, better picture! 
The reference I quoted above in regards to no known central massive black hole is found in the Astropix caption.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#117 2005-01-18 07:40:23

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.space.com/scienceastronomy/b … ml]Blazars:  Speed Demons of the Universe

*Whoa Nellie, hold onto your hat!  Jupiter-sized hot gas blobs cloaked in streams of ejected material from hyperactive galaxies, known as blazars, which travel at 99.9% the speed of light

They think black holes are involved.

Ponder the power of the fast moving superheated gas, known as plasma:

"To accelerate a bowling ball to the speed newly measured in these blazars would require all the energy produced in the world for an entire week,"   "And the blobs of plasma in these jets are at least as massive as a large planet."

Believe it or not, there is some competition though: 

ultra high-energy cosmic rays thought to originate in a collision of galaxy clusters are slamming into Earth's atmosphere at more than 99.9 percent of the speed of light. Measurements put the number at 99.9 followed by 19 more nines -- about as close to light-speed as you can get without splitting hairs.

Wow.  Particles are not light, but actual matter.  Thought to be mostly protons.  Amazing, huh?

--Cindy

::EDIT::  Don't want to forget this: 

"All the results from blazar jet observations are in agreement with Einstein's Theory of Special Relativity," Piner said. "The jets are accelerated right up to the edge of the speed-of-light barrier but not beyond, even though these are some of the most efficient accelerators in the universe."


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#118 2005-01-20 09:03:15

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

*LISA (Laser Interferometer Space Antennae):  Joint venture of NASA, ESA and European national space agencies. 

I'm pressed for time, so will quote:

A new space observatory called the Laser Interferometer Space Antennae, or LISA, will help help astronomers watch black holes as they gorge on new matter, growing larger in the process. These binges are thought to cause gravitational waves, which are ripples in spacetime. LISA consists of three spacecraft separated by 4.8 million km (3 million miles) which keep track of their relative positions very carefully...

*Will launch (hopefully) in 2008.  They're anticipating LISA detecting several BH events per year.  :up:

Predicted by Einstein, gravitational radiation has not yet been detected directly. These waves travel at light speed. Yet, unlike light waves, the subtle gravitational waves hardly interact with matter. A passing wave causes all matter to bob, like buoys on the ocean. LISA works by setting out three spacecraft -- buoys in spacetime -- and measuring the change in their separation as they bob in response to passing gravitational waves. The three LISA spacecraft will be separated from each other by over 3 million miles, while the gravitational waves alter the distance between them by far less than the width of an atom.

*Erm...well, that's a rather small width! 

These waves, Sigurdsson said, grow more intense in the weeks just before the larger black hole consumes the smaller object. That is when LISA could detect an imminent merger.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#119 2005-01-21 13:31:44

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.universetoday.com/am/publish … 2005]Swift sees birth of a new black hole

Summary - (Jan 21, 2005) NASA's Swift space observatory has seen its first Gamma-Ray Burst (GRB), probably the birth of a black hole. Swift detected the explosion on January 17, and turned to face it within 200 seconds - enough time to watch the explosion with its X-Ray telescope.  This is the first time an X-Ray observatory has ever watched a GRB while it was bursting, and not just the afterglow.

Likely the birth cry of a new black hole.  What a thought.  :up:

Am anxious to see approximately how many BH births are detected in a month or year.  [:edit:  Am also hoping for a breakdown according to varying BH weights, etc.]

--Cindy

P.S.:  And Swift is still yet in its checkout phase.  Looking marvellous!


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#120 2005-01-26 12:09:04

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.universetoday.com/am/publish … 612005]Sgr A* in the news again

*The supermassive BH at the center of our galaxy.  Kudos to ESA on this!  350 years ago Sgr A* was unleashing a million times more energy than it does today; which of course is recently, cosmologically speaking.  At that time it was "literally swamped in a tide of gamma rays."  Discusses the importance of Sgr B2 in the study -- it's a cloud of molecular hydrogen gas, about 350 ly from Sgr A*. 

This gamma-ray radiation is a direct consequence of Sgr A*'s past activity, in which gas and matter trapped by the hole's gravity are crushed and heated until they radiate X-rays and gamma rays, just before disappearing below the 'event horizon' - the point of no return from which even light cannot escape.

The team were able to unveil the history of Sgr A* thanks to a cloud of molecular hydrogen gas, called Sgr B2 and located about 350 light-years away from it, which acts as a living record of the hectic black hole's past.

Because of its distance from the black hole, Sgr B2 is only now being exposed to the gamma rays emitted by Sgr A* 350 years ago, during one of its 'high' states. This powerful radiation is absorbed and then re-emitted by the gas in Sgr B2, but this process leaves behind an unmistakable signature.

"Just a few years ago we could only imagine a result like this," Revnivtsev says. "But thanks to Integral, we now know it!"

Great.  smile

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#121 2005-01-27 12:46:17

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.universetoday.com/am/publish … 612005]Sgr A* in the news again

*The supermassive BH at the center of our galaxy.  Kudos to ESA on this!  350 years ago Sgr A* was unleashing a million times more energy than it does today; which of course is recently, cosmologically speaking.  At that time it was "literally swamped in a tide of gamma rays."  Discusses the importance of Sgr B2 in the study -- it's a cloud of molecular hydrogen gas, about 350 ly from Sgr A*. 

This gamma-ray radiation is a direct consequence of Sgr A*'s past activity, in which gas and matter trapped by the hole's gravity are crushed and heated until they radiate X-rays and gamma rays, just before disappearing below the 'event horizon' - the point of no return from which even light cannot escape.

The team were able to unveil the history of Sgr A* thanks to a cloud of molecular hydrogen gas, called Sgr B2 and located about 350 light-years away from it, which acts as a living record of the hectic black hole's past.

Because of its distance from the black hole, Sgr B2 is only now being exposed to the gamma rays emitted by Sgr A* 350 years ago, during one of its 'high' states. This powerful radiation is absorbed and then re-emitted by the gas in Sgr B2, but this process leaves behind an unmistakable signature.

"Just a few years ago we could only imagine a result like this," Revnivtsev says. "But thanks to Integral, we now know it!"

Great.  smile

--Cindy

*I wasn't able to get the ESA (source) web page to open yesterday, and found this http://www.spaceref.com/news/viewpr.htm … 5993]other article at spaceref.com.  I'm only posting it because it includes a link to a downloadable animation of the Sgr A* to Sgr B2 interaction (which the originally posted article doesn't host).  :up:  Check it out.

The ESA web page (which I'm able to open today) has the animation too...but I saw the animation first (just now) at spaceref.com.

The animation is subtle, but the effect is cool.  The reaction within the molecular hydrogen gas cloud Sgr B2 is mostly localized, but there's also a noticeable glow above and to the right.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#122 2005-01-28 06:12:55

Palomar
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Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.spaceref.com/news/viewpr.htm … 11]Mystery of magnetars solved?

*Compares magnetars with pulsars.  Scientists think magnetars are formed from supernovae of "some of the biggest stars," and that they are kind of neutron star --

a city-sized ball of neutrons created from a star's core when then the star explodes as a supernova at the end of its life.

Only 10 magnetars identified so far.  Pulsars are more common; more than 1500 found.

They're trying to figure out, though, why magnetars and pulsars are so different, given that they're found in similar locations and "born" in similar ways.

A map of the hydrogen gas shows a striking hole in the gas around the magnetar.

''The evidence points to this hole being a bubble carved out by the wind that flowed from the original star,'' says Naomi McClure-Griffiths of CSIRO's Australia Telescope National Facility, one of the researchers who made the map.

The characteristics of the hole indicate that the progenitor star must have been about 30 to 40 times the mass of the Sun.

Also discusses spin rate differences.  Article includes images.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#123 2005-01-29 07:39:09

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

http://www.spaceref.com/news/viewpr.html?pid=16024]NASA research balloon makes record-breaking flight over Antarctica

CREAM [Cosmic Ray Energetics And Mass experiment] is designed to explore the supernova acceleration limit of cosmic rays, the relativistic gas of protons, electrons and heavy nuclei arriving at Earth from outside the solar system.

*Launched from McMurdo Station on 16 December 2004.  Made 3 orbits around the South Pole and was aloft for 41 days and 22 hours.  :up:  Landed January 27, 410 miles from McMurdo.  They're in the process of recovering the payload. 

Says the balloon is made of material about as thick as sandwich wrap.  :laugh:  Balloon itself about 1-1/2 times the size of an American football field. 

An enormous balloon was needed to hoist the two-ton CREAM experiment to about 38,100 meters (125,000 feet). NASA's balloon expanded to a diameter of more than 137 meters (450 feet) and weighed 1,839 kilograms, (4,055 pounds).

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#124 2005-01-29 08:03:37

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

Yes, I saw this and was amazed that a balloon could lift 2 tons to 38 kilometres!
    It makes you wonder whether they could lift a lot more weight to that sort of altitude if they wanted to. Or is 2 tons getting close to some kind of limit?
                                                     ???


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#125 2005-01-29 09:46:29

DonPanic
Member
From: Paris in Astrolia
Registered: 2004-02-13
Posts: 595
Website

Re: Singularity - Black Holes, Gamma Rays, Magnetars, etc

Yes, I saw this and was amazed that a balloon could lift 2 tons to 38 kilometres!
    It makes you wonder whether they could lift a lot more weight to that sort of altitude if they wanted to. Or is 2 tons getting close to some kind of limit?

LO
He is 1.3 the density of H2.
If you do consider the mass lifted by Zeppelins. 2 tons shouldn't be a performancet. If the surface of the balloon is black and can heat the inner gaz with sunrays, difference of temperature between inner gaz and extremely cold atmosphere gaz should continue to inflate the balloon, and lifting performance will depend only on the volume the balloon can inflate,
meaning the mass of the enveloppe.
no?

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