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Electrical Universe DIScussion / Electric Universe meetings and talks
« Last post by electrobleme on February 24, 2016, 01:22:21 »
Electric Universe meetings and talks information

Latest information for EU theory meetings and talks coming up. Details of these from around the world including USA, Canada and England.



This year or future EU theory meetings

Phoenix, Arizona, USA 17 - 20 August: Thunderbolts Project EU 2017 (Electric Universe theory) Conference - everything discussed in a plasma universe

Previous EU theory conferences and talks

London, Great Britain 23 April 2016: Saturn Myth and Plasma Instability Petroglyphs (mythology, catastrophe)

Toronto, Canada 16 - 19 May 2016: Celestial Crisis and the Human Record (mythology, catastrophe)

Phoenix, USA 17 - 19 June 2016: Elegant Simplicity (Thunderbolts)

Arizona, USA 20 - 25 June 2016: EU geology tour (day after Thunderbolts conference)

London, England 26 February 2016: The History of the World & Then Some

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Hello again!

Was a long time I visited this very interesting forum. The Electric Universe Theory movement is accelerating and reaching light-speed worldwide. Now it seems to have touched the topic of water science too and recently I have seen a post on a very popular homeopathy research side on EM too. So it is becoming very popular.

In my kitchen I am performing some interesting experiments with the Joe Cell. This device accumulates a kind of energy which is known as orgone, named by Wilhelm Reich. You know, there was 3 giants in psychology during world war 1 and 2, Sigmund Freud, Carl Gustav Jung and Wilhelm Reich. But only Reich's books was burned by the government, two times (Germany and US)! So it must be something really hot if they resort to such desperate measures to preserve their unstable world view based on the futile materialism.

Now finally I started to investigate the Joe Cell myself. The inventors name is Joe Booker, an Australian fella, down under. Nice guy. A lot of youtube videos exist about him. He seems to be a already a legend ... and he does not use the internet at all. Some friends and "adepts of the Joe Cell" visited him and interviewed him about his discovery. Accidentally one of his HHO cell revealed to be a real orgone accumulator which stores abundantly this energy and it transmits it to the engine (and no, it is not hydrogen/oxygen gas, not even brown gas, but orgone/ether/qi). Inside the engine chamber the pure air implodes in a plasma vortex and sucks the pistons up without any friction (or so it seems).

I'm currently researching some of it's electrical properties and maybe you could take a look at it ...

- http://www.hydrogen2oxygen.net/en/joe-cell/
- http://www.hydrogen2oxygen.net/en/tag/joe-cell/

Regards
Peter
23
Malta / The Platypus Dinosaur Theory
« Last post by electrobleme on April 28, 2015, 06:22:43 »
The Platypus Dinosaur Theory

The Platypus Dinosaur Theory - natural evolution or electromagnetic evolution creating a dinosaur that is made up of different dinosaurs?

The dinosaur version of the platypus theory. A good theory predicts?

Quote
Fossil hunters in Chile have unearthed the remains of a bizarre Jurassic dinosaur that combined a curious mixture of features from different prehistoric animals.

The evolutionary muddle of a beast grew to the size of a small horse and was the most abundant animal to be found 145 million years ago, in what is now the Aysén region of Patagonia.

The discovery ranks as one of the most remarkable dinosaur finds of the past 20 years, and promises to cause plenty of headaches for paleontologists hoping to place the animal in the dinosaur family tree.

“I don’t know how the evolution of dinosaurs produced this kind of animal, what kind of ecological pressures must have been at work,”

“What’s surprising is that in this locality the most bizarre dinosaur is not the exception, but the rule. It is the most abundant animal we find,” he added.

... Chilesaurus had switched diets and become a vegetarian. Meat eaters tend to have sharp teeth and large heads supported by thick necks. Chilesaurus had a horny beak, flatter teeth for chomping plants, a small head and slender neck. “It’s a therapod that turned vegetarian,” said Novas.

... Other anatomical peculiarities have surprised paleontologists. Its forelimbs were stocky, like an allosaurus, and instead of sharp claws, it sported two stumpy fingers.

... The curious form of Chilesaurus is an extreme example of mosaic convergent evolution, where different parts of an animal adapt to the environment along the same path taken by other creatures.

... “It has an unbelievably weird mixture of anatomical features. If you found isolated bones from this one animal in different places you’d probably conclude that the bones came from completely different dinosaur groups, rather than representing one unusual species,” he said.

“Some of the bones look like they belong to an early theropod, others like they belong to a group of weird plant-eating theropods called therizinosauroids and yet others look like they belong to a completely different dinosaur group, the prosauropods. A truly odd mix.”
'Bizarre' Jurassic dinosaur discovered in remarkable new find  | theguardian.com
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Hubert Zeitlmair and the Malta Vortex pillar (maltadiscovery.org)

Dr Hubert Zeitlmair seems to be the person who discovered or rediscovered the apparent submerged Maltese Temple that he calls Gebel Gol-Bahar. I have no issue with this as you can tell from the above posts investigating and promoting this likely underwater structure/Temple.

I also have no issue with other peoples theories, as mine are not exactly mainstream.

But I have had to make this post as Dagmar and Doctor Hubert Zeitlmair on their site maltadiscovery.org to make sure that the work of plasma physicist Anthony Peratt combined with the work of the thunderbolts team (Marinus Anthony van der Sluijs, Wallace Thornhill, Don Scott etc) are not linked to his specific claim about the location of the ancient plasma instability seen in the skies by past civilisations (he says it was above Malta).

Making a mistake or getting information wrong is understandable and i reckon on this site i have done that more than most. Not being an expert in geology, history or plasma cosmology etc. But one of the few Electric Universe theory and plasma cosmology things that I have investigated are Peratt Instabilities and especially the Squatterman.

I was in email discussion with Zeitlmair about this but that has now stopped. So I have to make this post.



The Di.jet Object - A Depiction Of An Intense Aurora Pillar Above Malta

Hubert Zeitlmair and maltadiscovery.org claim that there was a high energy plasma discharge projected or found above the Maltese islands of Malta and Gozo. He calls it The Vortex pillar.

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For us there is no doubt that this intense, artificially created high-energy aurora column could be seen worldwide in a range of latitudes 50 degrees north to 33 degrees south. Rising above a set of 3 -Mounts, not exceeding an inclination angle of some 23.5 degrees off the horizon at latitude of 36 degrees north!

As luck would have it, we could identify the place of the pillar because when one observes the geography of the Earth there could only be one possibility:

The archipelago of Malta!

| The Di.jet Object

The work of the leading plasma instability scientist Anthony Peratt (A Peratt) does not suggest that the plasma discharge was seen anywhere near the equator. The Squatterman, Axis Mundi, Tree of Life (many many names for it) was seen in the polar regions.

If Malta's Temple Builders could carve the the Tree of Life then it had to be visible to them on one of the horizons, not projected or seen above the Maltese islands.

As can be confirmed by the various forms and evolution of the ancient petroglyphs (cave rock art) that show precisely the incredible plasma discharge seen in our skies. Over 100,000 petroglyphs have been mapped all over the world and analysed in the project and the findings show that these vary and change due to the location of the petroglyph carver, as expected with it being in the South polar region.

They DO NOT point to the high energy plasma discharge being above the islands of Malta and Gozo.

If Hubert Zeitlmair could provide the information of his research then I would be happy to review this post and his claims.

Plasma aurora was seen in the south (pole) region
Quote
In the first presentation we reported an analysis of a GPS database of petroglyphs recorded in the western US and British Columbia. These results indicated that a plasma flowing into the Earth’s south magnetic pole produced an intense aurora seen worldwide. In this paper we report the findings of logged petroglyphs in Venezuela, Guyana, Surinam, French Guiana and northern Brazil as well as some preliminary results from 93 countries. With decreasing longitude towards the Greenwich Meridian, petroglyphs appear to take on an increasingly easterly orientation. This swing from south to east can be tracked through the eastern US and the Caribbean Islands to the petroglyph sites shown below (dots), between 0 and 8 degrees north and 51 to 62 degrees west.

The morphological types of petroglyphs oriented eastwards appear to belong to instabilities much further out in the inflowing plasma. This suggests that the plasma, at least intense enough to to be seen at dawn and/or dusk, curved in from the east to flow inwards along the Earth’s southern magnetic pole. This geometry is further supported by ‘eclipsed’ pictographs in Australia.
Orientation of Z-Pinch Instabilities from an Intense Aurora as Recorded in Antiquity: South America | theplasmaverse.com

Links:
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Eta Carinae stars ultraviolet LASER light
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This is currently the only star thought to emit natural LASER light in ultraviolet wavelengths.
Eta Carinae | wikipedia



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Have you heard about the great LASER light show in the sky? A team led by K. Davidson (U. Michigan) and S. Johansson (U. Lund) discovered that the chaotically variable star Eta Carinae emits ultraviolet light in such a narrow band that it is most probably LASER light! This artist's vision depicts a model that could account for their Hubble Space Telescope observations. In this model, Eta Carinae emits many LASER beams from its surrounding cloud of energized gas. Infrared LASERS and microwave MASERS are extremely rare astrophysical phenomena, but this natural ultraviolet LASER is the first of its kind to be discovered.
Lasers in Eta Carinae | nasa


26
Are these Caucasus Dolmens with their holes in the walls similar to Malta's temples with their holes in the walls? Were Maltese Temples and Russian Dolmens used for electroculture, magnetoculture?

The holes are not for libration or to be spoken through by an Oracle but for the flow of electromagnetic energy in an Electric Universe?





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seeing in infrared light: Horsehead nebula and Flame nebula

What would you see in space if you could see the infrared light waves?

NASA's Spitzer Space Telescope gives a stunning infrared light view of the Orion Molecular Cloud Complex that includes the Horsehead nebula and Flame nebula.



Quote
The famous Horsehead nebula makes a ghostly appearance on the far right side of the image, but is almost unrecognizable in this infrared view. In visible-light images, the nebula has a distinctively dark and dusty horse-shaped silhouette, but when viewed in infrared light, dust becomes transparent and the nebula appears as a wispy arc.

The Horsehead is only one small feature in the Orion Molecular Cloud Complex, dominated in the center of this view by the brilliant Flame nebula (NGC 2024).
Image: Horsehead nebula viewed in infrared | phys.org
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What are Galatic Gamma-Ray Bursts? University of California, Berkeley explains

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Gamma-Ray Bursts

Enigmatic explosions from the distant universe


About once a day, something remarkable happens: the sky is lit up by a brilliant flash of energy. For a fleeting few seconds, this mysterious burst - coming from a seemingly random direction, different every time - ranks among the brightest objects in the sky.

Yet no one has ever witnessed such a flash directly: the energy comes almost entirely in the form of gamma rays, which human eyes cannot detect. Even if our eyes were sensitive to this extremely energetic form of radiation, gamma rays cannot penetrate the atmosphere. Only via orbiting satellites do we know of the presence of these mysterious blasts.

These events are known as gamma-ray bursts, or GRBs. They represent the most powerful explosions of energy in the cosmos since the Big Bang itself, corresponding to the equivalent of a thousand Earths vaporized into pure energy in a matter of seconds. One of the most enduring mysteries of the universe since their discovery in the 1960s, only recently have they begun to reveal their secrets.

What is a gamma-ray burst?
We define a gamma-ray burst based on its observational properties: an intense flash of gamma rays, lasting anywhere from a fraction of a second to up to a few minutes.

Gamma-ray bursts have a few other common features. We believe them to be beamed - the energy does not escape from the explosion everywhere equally, but is focused into a narrow jet (or more likely, two oppositely-directed jets.) The burst itself is also normally followed by a much longer-lived (but also much fainter) signal, visible at optical and other wavelengths. This so-called "afterglow", discovered only in the 1990s, allows us to pinpoint the origin of the GRB - something not possible from the short-lived gamma-ray signal alone.

Where do gamma-ray bursts come from?
For a long time, it was believed that GRBs must come from within our own Galaxy. It seemed impossible that they could be much more distant: for a gamma-ray burst to have come from a distant galaxy, it would have to be incredibly powerful to explain its observed brightness.

And yet we now know that, except perhaps for a few rare exceptions, most GRBs do indeed come from other galaxies - often from among the most distant galaxies in the known universe! The closest GRB known to date is still over a hundred million light-years away, and most of them come from billions of light years. To outshine our own Galaxy's closest stars in our sky from distances that are literally billions of times further away, stupendous amounts of energy are required.

What makes a gamma-ray burst?
No one knows for sure! Our best theory to date is based upon several observed facts. First, the only way to generate huge quantities is via gravitational collapse, and black holes can be very efficient at turning this energy into explosive power. Second, some of the closest GRBs appear to occur simultaneously with supernovae: explosions of stars at the end of their lives. Finally, almost all GRBs happen in galaxies containing large numbers of very massive stars.

Our conclusion: GRBs happen when an extremely massive star, at the end of its life, runs out of fuel and can no longer support itself. It collapses onto its core, crushing it into a black hole. Matter from the star falls towards the black hole at its center, and before it falls in, some of its energy is focused into powerful jets that pummel out of the north and south poles of the star, making a gamma-ray burst. The rest of the star explodes as a supernova soon afterwards.

Other origins are also possible. For example, some GRBs may be due to two ultra-dense neutron stars smashing into each other; and a small fraction may be magnetic eruptions on neutron stars in very nearby galaxies.
Gamma-Ray Bursts | berkeley.edu
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What are Gamma-Ray Burst Physics? Penn State University suggestions

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Gamma-ray bursts (GRB) are sudden, intense flashes of gamma-rays which, for a few blinding seconds, light up in an otherwise fairly dark gamma-ray sky. They are detected at the rate of about once a day, and while they are on, they outshine every other gamma-ray source in the sky, including the sun. Major advances have been made in the last three or four years, including the discovery of slowly fading x-ray, optical and radio afterglows of GRBs, the identification of host galaxies at cosmological distances, and finding evidence for many of them being associated with star forming regions and possibly supernovae. Progress has been made in understanding how the GRB and afterglow radiation arises in terms of a relativistic fireball shock model. This is described in a recent non-specialist GRB review or a more detailed review on GRB and afterglows. A summary of some of the specific research activities on GRB at Penn State is given in the previous link. The rest of this page gives a general overview of GRB.

Until a few years ago, GRB were thought to be just that, bursts of gamma-rays which were largely devoid of any observable traces at any other wavelengths. GRBs were first reported in 1973, based on 1969-71 observations by the Vela military satellites monitoring for nuclear explosions in verification of the Nuclear Test Ban Treaty. When these mysterious gamma-ray flashes were first detected, which did not come from Earth's direction, the first suspicion (quickly abandoned) was that they might be the product of an advanced extraterrestrial civilization. Soon, however, it was realized that this was a new and extremely puzzling cosmic phenomenon. A major advance occurred in 1991 with the launch of the Compton Gamma-Ray Observatory (CGRO), whose results have been summarized Fishman & Meegan 1995. The all-sky survey from the Burst and Transient Experiment (BATSE) onboard CGRO, which measured about 3000 bursts, showed that they were isotropically distributed, suggesting a cosmological distribution, with no dipole and quadrupole components. Some of the related work at Penn State on the cosmological GRB distribution is in the previous link. This isotropic distribution and the brightness distribution (log N- log P) provided strong support for a cosmological origin, and the detailed gamma-ray spectra and time histories imposed significant constraints on viable models, which led to the development of the fireball shock model.

A dramatic development in the last several years has been the measurement and localization of fading x-ray signals a number of GRBs by the Beppo-SAX satellite . These afterglows, lasting typically for weeks, made possible the optical and radio detection of afterglows, which, as fading beacons, mark the location of the fiery and brief GRB event. These afterglows in turn enabled the measurement of redshift distances, the identification of host galaxies, and the confirmation that GRB were, as suspected, at cosmological distances of the order of billions of light-years, similar to those of the most distant galaxies and quasars. Even at those distances they appear so bright that their energy output during its brief peak period has to be larger than that of any other type of source, of the order of a solar rest-mass if isotropic, or some percent of that if collimated. This energy output rate is comparable to burning up the entire mass-energy of the sun in a few tens of seconds, or to emit over that same period of time as much energy as our entire Milky Way does in a hundred years.

The energy density in a GRB event is so large that an optically thick pair/photon fireball is expected to form, which will expand carrying with itself some fraction of baryons. The main challenge in the early 90's was not so much the ultimate energy source, but how to turn this energy into predominantly gamma rays with the right nonthermal broken power law spectrum with the right temporal behavior. To explain the observations, the relativistic fireball shock model was proposed by Rees and Meszaros (1992, 1994), following pioneering earlier earlier work by Cavallo & Rees, Paczynski, Goodman and Shemi & Piran. This model has been quite succesful in explaining the various features of GRB, and a general discussion of it is given, e.g. here.

Much of the recent work has concentrated on GRB afterglows, a highlight of which was the successful prediction (Meszaros & Rees, ApJ 476, 232, Feb 10, 1997) of the general X-ray and optical behavior of GRB 970228. Since then more than 40 afterglows have been studied in detail, and a number of interestinf developments have occured. A prompt optcial flash (also predicted by theory) was found in one burst; many afterglows were found to be collimated, easing the energy constraints; X-ray lines believed to be from Iron and other metals have been reported from a number of bursts; and a new variety of softer bursts dubbed "X-ray flashes" has been identified, which are very similar to classical GRB but have a softer spectrum. Other work has concentrated on identifying the progenitors of GRB. Many of the afterglows identified by Beppo-SAX (all belonging to the class of "long" bursts, >10 s duration) have been shown to be associated with massive young stars, and in some cases a peculiar supernova "(hypernova") may be associated, as suggested by Woosley and Paczynski. This has led to work by Meszaros, Rees, Lazzati and others using X-ray lines as a diagnostic for distinguishing a massive progenitor. Other work has concentrated on modeling the central engine resposible for the energy release. The main ideas invoke the formation of a several solar mass black hole with a disrupted debris torus which is rapidly accrreted, which feeds an MHD or electron-positron-baryon jet. This can result from either the merger of a compact binary, such as a double neutron star (which is expected to lead to short bursts (< 10 s), observed in gamma-rays but so far without identified long-wavelenght afterglows) or by the collapse of the fast-totating core of a massive star, in some cases dubbed a collapsar, which leads to long bursts (>10 s) and could be associated with a suupernova-like phenomenon. More details and references are given in my recent review on GRB and afterglows.
Gamma-Ray Burst Physics | psu.edu
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Quote

Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe.[1] Bursts can last from ten milliseconds to several minutes. The initial burst is usually followed by a longer-lived "afterglow" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).[2]

Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the "short" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.[3]

The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years[4]). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.[5]

GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars.[6] Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.

On November 21, 2013, NASA released detailed data about one of the strongest gamma-ray bursts, designated GRB 130427A, that was observed on April 27, 2013.[7][8]

History
Gamma-ray bursts were first observed in the late 1960s by the U.S. Vela satellites, which were built to detect gamma radiation pulses emitted by nuclear weapons tested in space. The United States suspected that the USSR might attempt to conduct secret nuclear tests after signing the Nuclear Test Ban Treaty in 1963. On July 2, 1967, at 14:19 UTC, the Vela 4 and Vela 3 satellites detected a flash of gamma radiation unlike any known nuclear weapons signature.[9] Uncertain what had happened but not considering the matter particularly urgent, the team at the Los Alamos Scientific Laboratory, led by Ray Klebesadel, filed the data away for investigation. As additional Vela satellites were launched with better instruments, the Los Alamos team continued to find inexplicable gamma-ray bursts in their data. By analyzing the different arrival times of the bursts as detected by different satellites, the team was able to determine rough estimates for the sky positions of sixteen bursts[9] and definitively rule out a terrestrial or solar origin. The discovery was declassified and published in 1973 as an Astrophysical Journal article entitled "Observations of Gamma-Ray Bursts of Cosmic Origin".[10]

Many theories were advanced to explain these bursts, most of which posited nearby sources within the Milky Way Galaxy. Little progress was made until the 1991 launch of the Compton Gamma Ray Observatory and its Burst and Transient Source Explorer (BATSE) instrument, an extremely sensitive gamma-ray detector. This instrument provided crucial data that showed the distribution of GRBs is isotropic—not biased towards any particular direction in space, such as toward the galactic plane or the galactic center.[11] Because of the flattened shape of the Milky Way Galaxy, if the sources were from within our own galaxy they would be strongly concentrated in or near the galactic plane. The absence of any such pattern in the case of GRBs provided strong evidence that gamma-ray bursts must come from beyond the Milky Way.[12][13][14][15] However, some Milky Way models are still consistent with an isotropic distribution.[12][16]
Counterpart objects as candidate sources

For decades after the discovery of GRBs, astronomers searched for a counterpart at other wavelengths: i.e., any astronomical object in positional coincidence with a recently observed burst. Astronomers considered many distinct classes of objects, including white dwarfs, pulsars, supernovae, globular clusters, quasars, Seyfert galaxies, and BL Lac objects.[17] All such searches were unsuccessful,[nb 1] and in a few cases particularly well-localized bursts (those whose positions were determined with what was then a high degree of accuracy) could be clearly shown to have no bright objects of any nature consistent with the position derived from the detecting satellites. This suggested an origin of either very faint stars or extremely distant galaxies.[18][19] Even the most accurate positions contained numerous faint stars and galaxies, and it was widely agreed that final resolution of the origins of cosmic gamma-ray bursts would require both new satellites and faster communication.[20]

Afterglow
Several models for the origin of gamma-ray bursts postulated[21] that the initial burst of gamma rays should be followed by slowly fading emission at longer wavelengths created by collisions between the burst ejecta and interstellar gas. This fading emission would be called the "afterglow." Early searches for this afterglow were unsuccessful, largely due to the difficulties in observing a burst's position at longer wavelengths immediately after the initial burst. The breakthrough came in February 1997 when the satellite BeppoSAX detected a gamma-ray burst (GRB 970228[nb 2]) and when the X-ray camera was pointed towards the direction from which the burst had originated, it detected fading X-ray emission. The William Herschel Telescope identified a fading optical counterpart 20 hours after the burst.[22] Once the GRB faded, deep imaging was able to identify a faint, distant host galaxy at the location of the GRB as pinpointed by the optical afterglow.[23][24]

Because of the very faint luminosity of this galaxy, its exact distance was not measured for several years. Well before then, another major breakthrough occurred with the next event registered by BeppoSAX, GRB 970508. This event was localized within four hours of its discovery, allowing research teams to begin making observations much sooner than any previous burst. The spectrum of the object revealed a redshift of z = 0.835, placing the burst at a distance of roughly 6 billion light years from Earth.[25] This was the first accurate determination of the distance to a GRB, and together with the discovery of the host galaxy of 970228 proved that GRBs occur in extremely distant galaxies.[23][26] Within a few months, the controversy about the distance scale ended: GRBs were extragalactic events originating within faint galaxies at enormous distances. The following year, GRB 980425 was followed within a day by a coincident bright supernova (SN 1998bw), indicating a clear connection between GRBs and the deaths of very massive stars. This burst provided the first strong clue about the nature of the systems that produce GRBs.[27]

BeppoSAX functioned until 2002 and CGRO (with BATSE) was deorbited in 2000. However, the revolution in the study of gamma-ray bursts motivated the development of a number of additional instruments designed specifically to explore the nature of GRBs, especially in the earliest moments following the explosion. The first such mission, HETE-2,[28] launched in 2000 and functioned until 2006, providing most of the major discoveries during this period. One of the most successful space missions to date, Swift, was launched in 2004 and as of 2014 is still operational.[29][30] Swift is equipped with a very sensitive gamma ray detector as well as on-board X-ray and optical telescopes, which can be rapidly and automatically slewed to observe afterglow emission following a burst. More recently, the Fermi mission was launched carrying the Gamma-Ray Burst Monitor, which detects bursts at a rate of several hundred per year, some of which are bright enough to be observed at extremely high energies with Fermi's Large Area Telescope. Meanwhile, on the ground, numerous optical telescopes have been built or modified to incorporate robotic control software that responds immediately to signals sent through the Gamma-ray Burst Coordinates Network. This allows the telescopes to rapidly repoint towards a GRB, often within seconds of receiving the signal and while the gamma-ray emission itself is still ongoing.[31][32]

New developments over the past few years include the recognition of short gamma-ray bursts as a separate class (likely due to merging neutron stars and not associated with supernovae), the discovery of extended, erratic flaring activity at X-ray wavelengths lasting for many minutes after most GRBs, and the discovery of the most luminous (GRB 080319B) and the former most distant (GRB 090423) objects in the universe.[33][34] The most distant known GRB, GRB 090429B, is now the most distant known object in the universe.

Classification
While most astronomical transient sources have simple and consistent time structures (typically a rapid brightening followed by gradual fading, as in a nova or supernova), the light curves of gamma-ray bursts are extremely diverse and complex.[35] No two gamma-ray burst light curves are identical,[36] with large variation observed in almost every property: the duration of observable emission can vary from milliseconds to tens of minutes, there can be a single peak or several individual subpulses, and individual peaks can be symmetric or with fast brightening and very slow fading. Some bursts are preceded by a "precursor" event, a weak burst that is then followed (after seconds to minutes of no emission at all) by the much more intense "true" bursting episode.[37] The light curves of some events have extremely chaotic and complicated profiles with almost no discernible patterns.[20]

Although some light curves can be roughly reproduced using certain simplified models,[38] little progress has been made in understanding the full diversity observed. Many classification schemes have been proposed, but these are often based solely on differences in the appearance of light curves and may not always reflect a true physical difference in the progenitors of the explosions. However, plots of the distribution of the observed duration[nb 3] for a large number of gamma-ray bursts show a clear bimodality, suggesting the existence of two separate populations: a "short" population with an average duration of about 0.3 seconds and a "long" population with an average duration of about 30 seconds.[39] Both distributions are very broad with a significant overlap region in which the identity of a given event is not clear from duration alone. Additional classes beyond this two-tiered system have been proposed on both observational and theoretical grounds.[40][41][42][43]

Short gamma-ray bursts
Events with a duration of less than about two seconds are classified as short gamma-ray bursts. These account for about 30% of gamma-ray bursts, but until 2005, no afterglow had been successfully detected from any short event and little was known about their origins.[45] Since then, several dozen short gamma-ray burst afterglows have been detected and localized, several of which are associated with regions of little or no star formation, such as large elliptical galaxies and the central regions of large galaxy clusters.[46][47][48][49] This rules out a link to massive stars, confirming that short events are physically distinct from long events. In addition, there has been no association with supernovae.[50]

The true nature of these objects (or even whether the current classification scheme is accurate) remains unknown, although the leading hypothesis is that they originate from the mergers of binary neutron stars[51] or a neutron star with a black hole. The mean duration of these events of 0.2 seconds suggests a source of very small physical diameter in stellar terms: less than 0.2 light-seconds (about 37,000 miles—four times the Earth's diameter) This alone suggests a very compact object as the source. The observation of minutes to hours of X-ray flashes after a short gamma-ray burst is consistent with small particles of a primary object like a neutron star initially swallowed by a black hole in less than two seconds, followed by some hours of lesser energy events, as remaining fragments of tidally disrupted neutron star material (no longer neutronium) remain in orbit to spiral into the black hole, over a longer period of time.[45] A small fraction of short gamma-ray bursts are probably produced by giant flares from soft gamma repeaters in nearby galaxies.[52][53]

Long gamma-ray bursts
Most observed events (70%) have a duration of greater than two seconds and are classified as long gamma-ray bursts. Because these events constitute the majority of the population and because they tend to have the brightest afterglows, they have been studied in much greater detail than their short counterparts. Almost every well-studied long gamma-ray burst has been linked to a galaxy with rapid star formation, and in many cases to a core-collapse supernova as well, unambiguously associating long GRBs with the deaths of massive stars.[54] Long GRB afterglow observations, at high redshift, are also consistent with the GRB having originated in star-forming regions.[55]

Ultra-long gamma-ray bursts
These events are at the tail end of the long GRB duration distribution, lasting more than 10,000 seconds. They have been proposed to form a separate class, possibly the result of the collapse of a blue supergiant star.[56] Only a small number have been identified to date, their primary characteristic being their gamma ray emission duration. So far, the known and well established ultra long GRBs are GRB 091024A, GRB 101225A, and GRB 111209A.[57][58] A recent study,[59] on the other hand, shows that the existing evidence for a separate ultra-long GRB population with a new type of progenitor is inconclusive, and further multi-wavelength observations are needed to draw a firmer conclusion.

Tidal disruption events
This new class of GRB-like events was first discovered through the detection of GRB 110328A by the Swift Gamma-Ray Burst Mission on 28 March 2011. This event had a gamma-ray duration of about 2 days, much longer than even ultra-long GRBs, and was detected in X-rays for many months. It occurred at the center of a small elliptical galaxy at redshift z = 0.3534. There is an ongoing debate as to whether the explosion was the result of stellar collapse or a tidal disruption event accompanied by a relativistic jet, although the latter explanation has become widely favoured.

A tidal disruption event of this sort is when a star interacts with a supermassive black hole shredding the star, and in some cases creating a relativistic jet which produces bright emission of gamma ray radiation. The event GRB 110328A (also denoted Swift J1644+57) was initially argued to be produced by the disruption of main sequence star by a black hole of several million times the mass of the Sun,[60][61][62] although it has subsequently been argued that the disruption of a white dwarf by a black hole of mass about 10 thousand times the Sun may be more likely.[63]

Energetics and beaming
Gamma-ray bursts are very bright as observed from Earth despite their typically immense distances. An average long GRB has a bolometric flux comparable to a bright star of our galaxy despite a distance of billions of light years (compared to a few tens of light years for most visible stars). Most of this energy is released in gamma rays, although some GRBs have extremely luminous optical counterparts as well. GRB 080319B, for example, was accompanied by an optical counterpart that peaked at a visible magnitude of 5.8,[64] comparable to that of the dimmest naked-eye stars despite the burst's distance of 7.5 billion light years. This combination of brightness and distance implies an extremely energetic source. Assuming the gamma-ray explosion to be spherical, the energy output of GRB 080319B would be within a factor of two of the rest-mass energy of the Sun (the energy which would be released were the Sun to be converted entirely into radiation).[33]

No known process in the Universe can produce this much energy in such a short time. Rather, gamma-ray bursts are thought to be highly focused explosions, with most of the explosion energy collimated into a narrow jet traveling at speeds exceeding 99.995% of the speed of light.[65][66] The approximate angular width of the jet (that is, the degree of spread of the beam) can be estimated directly by observing the achromatic "jet breaks" in afterglow light curves: a time after which the slowly decaying afterglow begins to fade rapidly as the jet slows and can no longer beam its radiation as effectively.[67][68] Observations suggest significant variation in the jet angle from between 2 and 20 degrees.[69]

Because their energy is strongly focused, the gamma rays emitted by most bursts are expected to miss the Earth and never be detected. When a gamma-ray burst is pointed towards Earth, the focusing of its energy along a relatively narrow beam causes the burst to appear much brighter than it would have been were its energy emitted spherically. When this effect is taken into account, typical gamma-ray bursts are observed to have a true energy release of about 1044 J, or about 1/2000 of a Solar mass (M?) energy equivalent[69]—which is still many times the mass-energy equivalent of the Earth (about 5.5 × 1041 J). This is comparable to the energy released in a bright type Ib/c supernova and within the range of theoretical models. Very bright supernovae have been observed to accompany several of the nearest GRBs.[27] Additional support for focusing of the output of GRBs has come from observations of strong asymmetries in the spectra of nearby type Ic supernova[70] and from radio observations taken long after bursts when their jets are no longer relativistic.[71]

Short (time duration) GRBs appear to come from a lower-redshift (i.e. less distant) population and are less luminous than long GRBs.[72] The degree of beaming in short bursts has not been accurately measured, but as a population they are likely less collimated than long GRBs[73] or possibly not collimated at all in some cases.[74]

Progenitors
Because of the immense distances of most gamma-ray burst sources from Earth, identification of the progenitors, the systems that produce these explosions, is particularly challenging. The association of some long GRBs with supernovae and the fact that their host galaxies are rapidly star-forming offer very strong evidence that long gamma-ray bursts are associated with massive stars. The most widely accepted mechanism for the origin of long-duration GRBs is the collapsar model,[75] in which the core of an extremely massive, low-metallicity, rapidly rotating star collapses into a black hole in the final stages of its evolution. Matter near the star's core rains down towards the center and swirls into a high-density accretion disk. The infall of this material into a black hole drives a pair of relativistic jets out along the rotational axis, which pummel through the stellar envelope and eventually break through the stellar surface and radiate as gamma rays. Some alternative models replace the black hole with a newly formed magnetar,[76] although most other aspects of the model (the collapse of the core of a massive star and the formation of relativistic jets) are the same.

The closest analogs within the Milky Way galaxy of the stars producing long gamma-ray bursts are likely the Wolf–Rayet stars, extremely hot and massive stars which have shed most or all of their hydrogen due to radiation pressure. Eta Carinae and WR 104 have been cited as possible future gamma-ray burst progenitors.[77] It is unclear if any star in the Milky Way has the appropriate characteristics to produce a gamma-ray burst.[78]

The massive-star model probably does not explain all types of gamma-ray burst. There is strong evidence that some short-duration gamma-ray bursts occur in systems with no star formation and where no massive stars are present, such as elliptical galaxies and galaxy halos.[72] The favored theory for the origin of most short gamma-ray bursts is the merger of a binary system consisting of two neutron stars. According to this model, the two stars in a binary slowly spiral towards each other due to the release of energy via gravitational radiation[79][80] until the neutron stars suddenly rip each other apart due to tidal forces and collapse into a single black hole. The infall of matter into the new black hole produces an accretion disk and releases a burst of energy, analogous to the collapsar model. Numerous other models have also been proposed to explain short gamma-ray bursts, including the merger of a neutron star and a black hole, the accretion-induced collapse of a neutron star, or the evaporation of primordial black holes.[81][82][83][84]

An alternative explanation proposed by Friedwardt Winterberg is that in the course of a gravitational collapse and in reaching the event horizon of a black hole, all matter disintegrates into a burst of gamma radiation.[85]

Emission mechanisms
The means by which gamma-ray bursts convert energy into radiation remains poorly understood, and as of 2010 there was still no generally accepted model for how this process occurs.[86] Any successful model of GRB emission must explain the physical process for generating gamma-ray emission that matches the observed diversity of light curves, spectra, and other characteristics.[87] Particularly challenging is the need to explain the very high efficiencies that are inferred from some explosions: some gamma-ray bursts may convert as much as half (or more) of the explosion energy into gamma-rays.[88] Recent observations of the bright optical counterpart of GRB 080319B, whose light curve was correlated with the gamma-ray light curve,[64] has suggested that inverse Compton may be the dominant process in some events. In this model, pre-existing low-energy photons are scattered by relativistic electrons within the explosion, augmenting their energy by a large factor and transforming them into gamma-rays.[89]

The nature of the longer-wavelength afterglow emission (ranging from X-ray through radio) that follows gamma-ray bursts is better understood. Any energy released by the explosion not radiated away in the burst itself takes the form of matter or energy moving outward at nearly the speed of light. As this matter collides with the surrounding interstellar gas, it creates a relativistic shock wave that then propagates forward into interstellar space. A second shock wave, the reverse shock, may propagate back into the ejected matter. Extremely energetic electrons within the shock wave are accelerated by strong local magnetic fields and radiate as synchrotron emission across most of the electromagnetic spectrum.[90][91] This model has generally been successful in modeling the behavior of many observed afterglows at late times (generally, hours to days after the explosion), although there are difficulties explaining all features of the afterglow very shortly after the gamma-ray burst has occurred.[92]

Rate of occurrence and potential effects on life on Earth
All GRBs observed to date have occurred well outside the Milky Way galaxy and have been harmless to Earth. However, if a GRB were to occur within the Milky Way, and its emission were beamed straight towards Earth, the effects could be devastating for the planet. Currently, orbiting satellites detect on average approximately one GRB per day. The closest observed GRB as of March 2014 was GRB 980425, located 40Mpc[93] (130 million light years) away in a (z=0.0085) SBc-type dwarf galaxy.[94] GRB 980425 was far less energetic than the average GRB and was associated with the Type Ib supernova SN 1998bw.[95]

Estimating the exact rate at which GRBs occur is difficult, but for a galaxy of approximately the same size as the Milky Way, the expected rate (for long-duration GRBs) is about one burst every 100,000 to 1,000,000 years.[96] Only a small percentage of these would be beamed towards Earth. Estimates of rate of occurrence of short-duration GRBs are even more uncertain because of the unknown degree of collimation, but are probably comparable.[97]

Since GRBs are thought to involve beamed emission along two jets in opposing directions, only planets in the path of these jets would be subjected to the high energy gamma radiation.[98]

Depending on its distance from Earth, a GRB and its ultraviolet radiation could damage even the most radiation resistant organism known, the bacterium Deinococcus radiodurans. These bacteria can endure 2,000 times more radiation than humans. Life surviving an initial onslaught, including those located on the side of the earth facing away from the burst, would have to contend with the potentially lethal after-effect of the depletion of the atmosphere's protective ozone layer by the burst.[99]

Hypothetical effects of gamma-ray bursts in the past
GRBs close enough to affect life in some way might occur once every five million years or so – around a thousand times since life on Earth began.[100]

The major Ordovician–Silurian extinction event of 450 million years ago may have been caused by a GRB. The late Ordovician species of trilobite that spent some of its life in the plankton layer near the ocean surface was much harder hit than deep-water dwellers, which tended to stay put within quite restricted areas. Usually it is the more widely spread species that fare better in extinction, and hence this unusual pattern could be explained by a GRB, which would probably devastate creatures living on land and near the ocean surface, but leave deep-sea creatures relatively unharmed.[5]

A case has been made that the cause of the carbon 14 (and Be 10) spike in 774 or 775 was the result of a short GRB.

Hypothetical effects of gamma-ray bursts in the future
The greatest danger is believed to come from Wolf–Rayet stars, regarded by astronomers as likely GRB candidates. When such stars transition to supernovae, they may emit intense beams of gamma rays, and if Earth were to lie in the beam zone, devastating effects may occur. Gamma rays would not penetrate Earth's atmosphere to impact the surface directly, but they would chemically damage the stratosphere.[5]

For example, if WR 104, at a distance of 8,000 light-years, were to hit Earth with a burst of 10 seconds duration, its gamma rays could deplete about 25 percent of the world's ozone layer. This would result in mass extinction, food chain depletion, and starvation. The side of Earth facing the GRB would receive potentially lethal radiation exposure, which can cause radiation sickness in the short term, and, in the long term, results in serious impacts to life due to ozone layer depletion.[5]

Effects after exposure to the gamma-ray burst on Earth's atmosphere
Longer-term, gamma ray energy may cause chemical reactions involving oxygen and nitrogen molecules which may create nitrogen oxide then nitrogen dioxide gas, causing photochemical smog. The GRB may produce enough of the gas to cover the sky and darken it. Gas would prevent sunlight from reaching Earth's surface, producing a "cosmic winter" effect - a similar situation to an impact winter, but not caused by an impact. GRB-produced gas could also even further deplete the ozone layer.
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