Singularity - Black Holes, Gamma Rays, Magnetars, etc

Palomar · 2005-04-07 09:38:31

http://antwrp.gsfc.nasa.gov/apod/ap000612.html]WOW

*Now -that's- a photo! Is galaxy NGC 4438. Aprox 50 million l/y from us.

Astronomers speculating that pinkish-colored bubble might have been created by a central massive BH.

As gas swirls around the black hole, gravity and friction pull it in and heat it up. Some of the hot gas then falls into the black hole, but not all - some gas gets so hot it shoots out the poles in fast jets. When these jets impact nearby material, they heat it up and cause the detected glow.

The bubble measures aprox 800 l/y across.

--Cindy

Palomar · 2005-04-07 11:49:46

http://www.universetoday.com/am/publish … 05]Fertile grounds for largest BH's in the universe?

*Study involves extremely distant galaxies, called "submillimeter galaxies" because they were originally ID'd by the JCMT in Hawaii. They are very luminous galaxies with lots of gaseous material, creating 1 star per day (which is 100 times more than our Milky Way galaxy creates in a day).

The Chandra X-ray data show that the supermassive black holes in the galaxies were also growing at the same time.

extremely luminous adolescent galaxies and their central black holes underwent a phenomenal spurt of growth more than 10 billion years ago. This concurrent black hole and galaxy growth spurt is only seen in these galaxies and may have set the stage for the birth of quasars - distant galaxies that contain the largest and most active black holes in the Universe.

Includes illustration.

--Cindy

Palomar · 2005-04-13 10:37:17

*From http://www.universetoday.com.]http://www.universetoday.com. A short paragraph accompanies two audio links. Will have to access the web site itself to listen via the first link; the 2nd is a Podcast:

Audio: Dark Energy Stars
Apr 11, 2005 - Black holes... you know. Cosmic singularities that can contain the mass of billions of stars like our Sun. Where the pull of gravity is so strong, nothing, not even light can escape their fearsome grasp. They're the source of much discussion, indirect observation and science fiction speculation. But according to George Chapline from Lawrence Livermore National Laboratory in California, they don't exist. Instead we have dark energy stars, which are connected to that mysterious force accelerating the expansion of the Universe.
Listen to the interview: Dark Energy Stars (5.1 mb)
Or subscribe to the Podcast: universetoday.com/audio.xml

I'm going to listen to it later today.

--Cindy

Palomar · 2005-04-14 09:05:54

http://www.spaceref.com/news/viewpr.htm … 33]Roasted -vs- Spaghettified

*No thanks to either, Monty. I'll take what's behind Door #3! LOL!

Now scientists think you'd be more likely to get roasted if you tumbled into a supermassive black hole. :-\ Really cool (and brief) article. I love speculation like this.

--Cindy

P.S.: Check out the bit about double event horizon.

Palomar · 2005-04-15 08:10:07

http://www.spacedaily.com/news/blackhole-05r.html]Early universe packed with mini-black holes?

*From a Cambridge research group. They're going to make a presentation on this to Physics 2005, a conference in Warwick. Speculating about the possibility of small BH's having grown independently, then merging to create supermassive BH's.

Such a merger begins with two black holes going into orbit around each other, spiralling ever closer together.
In the cataclysmic blast of energy when they finally merge, any asymmetry can send the resulting black hole flying off into space.
"If this happened," says Haehnelt, "we might find the occasional galaxy with its central supermassive black hole missing."

Article also mentions the cosmic microwave background, which has been "traveling" since only 400,000 years after the Big Bang. There's new evidence of 10% - 15% CMB scatter, which indicates an unexpected re-warming of the universe.

--Cindy

Palomar · 2005-04-27 10:50:08

http://antwrp.gsfc.nasa.gov/apod/ap000628.html]BATSE GRB Final Sky Map

*Oh yeah, that's

Is from a former mission.

The BATSE modules that flew on the Compton Gamma Ray Observatory allowed more insight into enigmatic gamma-ray burst (GRB) explosions than ever before. From 1991-2000, BATSE detected 2704 GRBs, much more than ever previously recorded. The above final sky map of GRB locations (and fluence) shows them to occur at random locations on the sky - strong evidence that GRBs occur across our universe and not in sky bands indicative of our Solar System or our Galaxy.

It also recorded gamma-ray flares from Sol -and- discovered Terrestrial Gamma Flashes (that phenomenon was mentioned in the previous page of this thread; I currently can't see the date of it). Compton GRO was crashed into the ocean at mission's end.

--Cindy

Palomar · 2005-04-29 11:25:35

*Relative to the post above this one:

http://antwrp.gsfc.nasa.gov/apod/ap0503 … ]Gamma-ray Earth

Funky. Image was constructed from 7 years' exposure of the now-deceased Compton GRO.

Brightest near the edge and faint near the center, the picture indicates that the gamma rays are coming from high in Earth's atmosphere. The gamma rays are produced as the atmosphere interacts with high energy cosmic rays from space, blocking the harmful radiation from reaching the surface.

-*-

http://antwrp.gsfc.nasa.gov/apod/ap0201 … ]Gamma-ray Sky

Obtained in early 1990s (same source as above).

What if you could see gamma rays? If you could, the sky would seem to be filled with a shimmering high-energy glow from the most exotic and mysterious objects in the Universe.
...
The brightest spots in the galactic plane (right of center) are pulsars, spinning magnetized neutron stars formed in the violent crucibles of stellar explosions. Above and below the plane, quasars, believed to be powered by supermassive black holes, produce gamma-ray beacons at the edges of the universe. The nature of many of the fainter sources remains unknown.

--Cindy

srmeaney · 2005-04-29 13:55:23

That stuff about matter being "crushed out of existence" is really just a convenient way of describing the indescribable!! In a manner of speaking, once matter crosses the event horizon, it is "out of existence" - at least as far as this universe is concerned. Some people have speculated that the matter which disappears into a black hole in this universe, emerges out of a 'white hole' in another universe!

It's unfolded in the other direction because it cant unfold in our direction. A white hole is simultaneously a black hole With negative time. The contents are simply doing a ten dimensional 180.

Palomar · 2005-05-04 14:13:53

*A study from the National Science Foundation which complements especially my post of April 29. As the article deals with gamma rays, I'm placing it here; especially as I've already posted articles in this thread relative to TGFs and Compton GRO.

And as I'm currently half brain-dead from serious sleep deprivation, I'll opt to mostly copy and paste the pertinent (IMO) points:

http://www.spaceref.com/news/viewpr.htm … 6795]Gamma rays from T-storms?

Duke University engineers have led the most detailed analyses of links between some lightning events and mysterious gamma ray emissions that emanate from earth's own atmosphere. Their study suggests that this gamma radiation fountains upward from starting points surprisingly low in thunderclouds. Counter-intuitively, these strong gamma outbursts also seem to precede associated lightning discharges by a split second.
"All of this comes as a huge surprise," said Steven Cummer, an assistant professor of electrical and computer engineering at Duke's Pratt School of Engineering. "These are higher energy gamma rays than come from the sun. And yet here they are coming from the kind of terrestrial thunderstorm that we see here all the time."

HIGHER energy gamma rays than from Sol. Cool!

Natural emissions of gamma rays, the most energetic forms of light, are usually triggered only by high-energy events in outer space. Such events include thermonuclear reactions within the sun, interactions between cosmic rays and black-hole-creating star collapses.
But in 1994, scientists using the Compton Gamma Ray Observatory satellite first detected gamma rays seemingly originating near the earth's surface. And researchers quickly found evidence that those emissions were connected to lightning, Cummer said.

Fan-tas-tic! I love stuff like this.

--Cindy

DanielCook · 2005-05-09 11:26:35

Hey Cindi:

No sure whether you've seen http://www.space.com/scienceastronomy/0 … .html]this at space.com yet.

Some astronomers observed the formation of a low-mass black-hole from the (aparent) collision/merger of two neutron stars.

Over 2.2 billion years ago!

Daniel.

Palomar · 2005-05-09 11:44:02

Hey Cindi:
No sure whether you've seen this at space.com yet.
Some astronomers observed the formation of a low-mass black-hole from the (aparent) collision/merger of two neutron stars.
Over 2.2 billion years ago!
Daniel.

*Wow! Hi Daniel; no, hadn't seen it yet. Was offline for a few hours. Thanks for posting it. :band:

Yeah -- 2.2 billion years ago, its light reaching us just this morning. WAY TO GO, SWIFT! Says Swift "just barely" caught the x-ray afterglow; it was "barely detectable" and only observable for a "few hundred seconds."

Astronomers photographed a cosmic event this morning which they believe is the birth of a black hole, SPACE.com has learned.
A faint visible-light flash likely heralds the merger of two dense neutron stars to create a relatively low-mass black hole, said Neil Gehrels of NASA's Goddard Space Flight Center. It is the first time an optical counterpart to a very short-duration gamma-ray burst has ever been detected.

Awesome!

--Cindy

P.S.: It's always mind-blowing to consider what is said in the final sentence of the article:

Each burst can briefly outshine an ENTIRE GALAXY.

DanielCook · 2005-05-09 16:19:23

Someone once said that the universe is both stranger than we think, and stranger than we can think ...

Sagan I think. Or Clarke.

Speaking of things glowing brighter than the galaxy - I remember Nova mentioning that gamma ray burst of that magnitude happens fairly regularly (in astronomical terms) - except no one has quite yet figured out why...

Palomar · 2005-05-10 06:06:15

I remember Nova mentioning that gamma ray burst of that magnitude happens fairly regularly (in astronomical terms) - except no one has quite yet figured out why...

*Once a day, on average, according to the article.

--Cindy

::edit:: Well, a gamma ray burst per day; not sure about the frequency of one of yesterday's magnitude. Haven't time to re-read the article just now.

MarsDog · 2005-05-17 15:59:52

http://www.findarticles.com/p/articles/ … oretically, each mini black hole would have a mass of just 10 micrograms and exist for just a split second before exploding in a shower of particles--perhaps the same type of quark shower detected by the observatories in Bolivia and Tajikistan.

10 micrograms = 10^-8 kg

E=MC^2 = 10^-8 (3 10^8)^2 = 9 10^8 joules = 900 MJ

1 kWh = 3,600,000 joules

E = 9 10^8 / 3.6 10^6 = 2.5 10^2 = 250 KWh

Say, 10 cents per KWh - gives $25 per black hole.

http://www.google.com/search?q=miniatur … a=N]google the mini black holes

Palomar · 2005-05-18 15:33:16

*Hi MarsDog. Wish I could muster up a reply to your interesting post, but I'm allergic to numbers. :-\ (No kidding). Especially when letters of the alphabet are tossed in alongside.

-*-

M83 "mystery." It's speculated to have
http://www.universetoday.com/am/publish … 52005]twin supermassive black holes "churning" at the heart of it. But could also be massive star clusters.

Gorgeous photo of M83 accompanies the article. Is 15 million l/y away.

...a team of investigators capturing near-visible light are telling us that this relatively light-weight - but beautifully-formed face-on galaxy - is being churned up by the presence of not one but two mass-concentrations (nuclei) which could potentially take the form of supermassive black holes (SMBHs). Perhaps most surprising of all is the fact that neither nuclei lies exactly at the galaxy's very core.

Among the many interesting features seen using the above approach, the investigating team reports "a bright small red arc (emerging) to the SW" and "a giant star forming arc" – one first reported by astronomers in 1991. Within that arc to the northeast of the nucleus, "several star clusters are present". These clusters were first noted in 2001. The team also reports that "Going counterclockwise through the arc, a highly obscured region is located with a large number of dust patches and a star forming region emerging from the dust". All this lies some 250 LYs west of the galaxy’s nucleus.

Check out especially the 4th and 3rd to the last paragraphs.

--Cindy

::EDIT:: Intriguing too (towards very bottom of article, discussing major-mergers and minor-mergers):

In the case of a minor-merger event, a dwarf satellite galaxy falls into the host. Due to dynamical friction, 'the intruder' falls toward the main nucleus of the galaxy while orbiting it. The global appearance of the host galaxy, if we consider a giant spiral, would not be affected."

Wouldn't be affected, huh? Must be easily absorbed, then. ?

MarsDog · 2005-05-18 18:23:09

Was confusing since I did not realize that E had 2 meanings.
One for Energy - other for Exponential - 10 to the power of.

I have edited E to 10^ (the number of times to move decimal point).

Mini black hole converted to energy 9 10^8 joules = 900 MJ

http://home.earthlink.net/~jimlux/energies.htm]Energy comparisions

If all converted to heat; 450 pounds of high explosive.
Drive 418 miles, a tank of gas.

Will be intersting what elementary particle are produced, maybe some newer seen before. Particles antiparticles revealing black hole structure ? Black hole contents hiding in extra dimensions ?

Palomar · 2005-05-19 06:31:43

Was confusing since I did not realize that E had 2 meanings.
One for Energy - other for Exponential - 10 to the power of.

*Cool. I didn't know that.

http://www.space.com/scienceastronomy/0 … html]LOPES from Germany

Cosmic rays, particularly high-energy CR's. The orange blob in the photo is a radio flash, "which lasts for about 30 billionths of a second."

Article mentions electrons, positrons and muons.

Says CR's possess 100 million times more energy than can be created in man-made accelerators; those are called UHECRs (ultra-high energy cosmic rays). They're speculating UHECRs originate from large black holes or colliding galaxies, but there's a mystery:

cosmic "stuff" along the way will slow – or even outright destroy – high-energy particles traveling these great distances.
Added to this quandary is the fact that no one knows the true identity of UHECRs.

They're suspecting protons, iron, gamma rays and neutrinos are "the culprits."

"It is amazing that with simple FM radio antennas we can measure the energy of particles coming from the cosmos," said Heino Falcke, spokesperson for the LOPES collaboration. "If we had sensitive radio eyes, we would see the sky sparkle with radio flashes."

Actually, our eyes would also need to be very fast, since the radio bursts only last a few billionths of a second. But during that short time, they are the brightest spots in the radio sky. LOPES picks up the flashes between 43 and 73 MHz – just below the FM dial.

--Cindy

reddragon · 2005-05-19 14:15:25

Say, 10 cents per KWh - gives $25 per black hole.

Are you saying we should use mini black holes to produce energy? I suppose it might be feasible one day, but I can't really think of any good way to do it. You'd have to capture them as they enter the upper atmosphere and before they explode. There is also a limited supply of natural black holes. Making our own would also probably not be feasible, as it would take more energy to make them than you would get out.

MarsDog · 2005-05-19 17:49:28

I am trying to understand the energy involved in the theoretically smallest black hole. Even the smallest one has a lot of energy. Would turn cup of coffe into plasma, together with the person drinking it.

Really interesting is the possibility of testing multiple dimensions of string theories. How is space and time tied together at vanishingly short distances, could give clues to the universe at large scale.

Black hole has spin and charge, so it is not a singularity.
What is inside may be deduced from the mini (white) holes.
If it gobbled up matter, will it explode into matter/antimatter pairs of particles ? Extremely significant theoretically.

Palomar · 2005-05-21 09:42:21

Black hole has spin and charge, so it is not a singularity.
What is inside may be deduced from the mini (white) holes.
If it gobbled up matter, will it explode into matter/antimatter pairs of particles ? Extremely significant theoretically.

*Fascinating, all of it! :up: Black holes are the grooviest of universal phenomena, aside from magnetars.

What do you mean by "charge," exactly? I have an idea in mind, but you might be using the word differently. Please explain?

http://antwrp.gsfc.nasa.gov/apod/ap050515.html]Gamma ray connection with gold?

Unusual and brief article, but intriguing.

Since neutron star collisions are also suggested as the origin of short duration gamma-ray bursts, it is possible that you already own a souvenir from one of the most powerful explosions in the universe.

--Cindy

Palomar · 2005-05-24 05:15:29

http://www.universetoday.com/am/publish … ]Wormholes? Unlikely

*Interview with Dr. Stephen Hsu of the University of Oregon. Audio link included.

He's of the opinion that there are no "easy access" routes to other stars, let alone the other side of the galaxy.

--Cindy

Shaun Barrett · 2005-05-24 05:54:42

Hmmm.
Yes, he's probably right but then there's always the http://www.npl.washington.edu/AV/altvw8 … Alcubierre Warp Drive.
In this theoretically sound concept:-

... new space is rapidly being created (like an expanding universe) at the back side of the moving volume, and existing space is being annihilated (like a universe collapsing to a Big Crunch) at the front side of the moving volume. Thus, a space ship within the volume of the Alcubierre warp (and the volume itself) would be pushed forward by the expansion of space at its rear and the contraction of space in front.

A diagrammatic way of representing this is as follows:-

A further explanatory excerpt:-

Since a ship at the center of the moving volume of the metric is at rest with respect to locally flat space, there are no relativistic mass increase or time dilation effects. The on-board spaceship clock runs at the same speed as the clock of an external observer, and that observer will detect no increase in the mass of the moving ship, even when it travels at FTL speeds. Moreover, Alcubierre has shown that even when the ship is accelerating, it travels on a free-fall geodesic. In other words, a ship using the warp to accelerate and decelerate is always in free fall, and the crew would experience no accelerational gee-forces.

The trouble with the Alcubierre Warp Drive is that calculations reveal creating a warp big enough to accommodate a spaceship within its boundaries requires simply staggering quantities of energy - and negative energy at that!
But now, there's http://www.npl.washington.edu/AV/altvw99.html]The Micro-Warp Drive, devised by general relativity theorist Chris Van Den Broeck of the Catholic University of Leuven in Belgium:-

Now, however, Dr. Van Den Broeck has proposed an improvement on Alcubierre’s scheme that appears to solve many of its problems. Van Den Broeck observed that most of the undesirable effects of Alcubierre’s drive scale with the volume or surface area of the warp bubble. Therefore, his simple solution is to make the radius of the warp bubble so small that the problems go away. In doing this, he makes use of another trick from general relativity. The interior volume of a region of space bounded by a closed surface, because of space curvature, can be made much larger than the flat-space volume bounded by its surface.

It may well be true that we'll never cross interstellar distances in minutes, but I'd rather reserve judgment for a few years just in case this line of research eventually proves fruitful.
Strange things do happen! :;):

Palomar · 2005-05-24 13:27:48

Hmmm.
Yes, he's probably right but then there's always the http://www.npl.washington.edu/AV/altvw8 … Alcubierre Warp Drive.
In this theoretically sound concept:-
... new space is rapidly being created (like an expanding universe) at the back side of the moving volume, and existing space is being annihilated (like a universe collapsing to a Big Crunch) at the front side of the moving volume. Thus, a space ship within the volume of the Alcubierre warp (and the volume itself) would be pushed forward by the expansion of space at its rear and the contraction of space in front.
...snip...
It may well be true that we'll never cross interstellar distances in minutes, but I'd rather reserve judgment for a few years just in case this line of research eventually proves fruitful.
Strange things do happen! :;):

*Hi Shaun: I've heard of this, but forgot about it until you mentioned it. Will read the article. So far it sounds truly awesome.

Thanks for posting it.

--Cindy

Palomar · 2005-05-27 06:05:27

http://www.spaceflightnow.com/news/n050 … Hypernovae: Origins of gamma-ray bursts?

*They're speculating gamma-ray bursts originate from naked carbon/oxygen stars as they flatten while collapsing into black holes.

These incidents are Type Ic supernovae, sometimes called hypernovae.

The burst itself is described as a "collimated beam" -- akin to the cone light emitted by a lighthouse.

The most popular scenario is that a collapsing star generates two highly collimated beams or jets of particles and energy that flash outward from the poles. The particles and energy generate a shock wave when they hit gas and dust around the star, which in turn accelerates particles to energies at which they emit high-energy light: gamma rays and X-rays. The initial burst fades over a few seconds, but the resulting shock waves (the "afterglow") can be visible to optical, radio and X-ray telescopes for days after the explosion.

The model explains how an asymmetric exploding star produces a tight beam of matter and energy out of each pole that generates an intense burst of gamma rays, while the absence of a hydrogen and helium envelope would allow the blast to escape.
"It appears that to produce a gamma-ray burst, a core-collapse supernova needs to be both asymmetric in its explosion mechanism, so that there is a natural axis along which matter can more easily squirt, and free of a hydrogen envelope, so that the jet doesn't have to pummel through a lot of material,"

There is one item in the article which seems contradictory to me. It states:

It took until 1997 to establish that they originate outside our Milky Way Galaxy

???

Guess I'll have to re-read previous articles posted in this thread, because I could have sworn GRB's also occur -in- our Milky Way Galaxy too.

--Cindy

::EDIT:: Must include this:

The collapsar theory proposes that the solid iron sphere at the very core of the star collapses under gravity to a black hole, but that the split-second collapse takes place in a unique way. As the iron and surrounding matter fall inward, the spin of the core increases, flattening the in-falling material into a disk that flows inward along the equator. The congestion of in-falling matter pushes some of it right back out along the path of least resistance - the two blowholes at either pole.

Palomar · 2005-05-30 07:00:07

*In conjunction with the post above, here's http://www.space.com/scienceastronomy/0 … ml]another similar article.

But some additional interesting info about Type Ic supernovae:

Astronomers have recently observed several GRBs associated with Type Ic supernovae. But on October 25, 2003, a Type Ic, named SN 2003jd, went bang but had no burst.
Follow-up observations by both the Keck and Subaru telescopes in Hawaii did, however, reveal two high-speed jets – one moving towards us, the other going away. The fact that we see two beams means that we are not lined up with the axis – but instead are viewing from an angle.
The interpretation is that this event would have been seen as a GRB if we had been staring down the barrel of one of the jets.
"These observations suggest that the collapsar model is probably correct and that some of these Type Ic supernovae appear to be off-axis gamma-ray bursts, in which the gamma-ray burst is pointing in some direction other than Earth," said Ryan Foley, also from UC Berkeley.

They're saying that, thanks to Swift, we're finally receiving real data assisting in determining what exactly GRB's are.

The fact that there was no afterglow seen in visible light argues for this burst being the result of a merger between two neutron stars, two black holes, or a combination of the two.

Swift is worth its weight in gold.

--Cindy

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