| | | Page 1, 2, 3 | Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event.......
| Scarlet Witch nli
1/16/2005 6:11 PM
Report abusive post | Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event.......
| Quote |
What do you know about it or should I say think you know about it? |
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| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
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| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Evidently nothing so tell us already. |
| Anonymous Coward
12/8/2005 10:12 AM | | Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Tell us what you know, Scarlet. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Iīm pretty sure it was Aussie Bloke who made reference to something discovered in 1979 that the govt has been keeping silent about all these years.
What is it? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Is it getting ready to climb up our gazoo? |
| Proof
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
March 5th, 1979 ....
At 10:51 A.M. Eastern Standard Time, far out in space, two Soviet interplanetary space probes, Venera 11 and Venera 12, were drifting through the inner solar system when they were walloped by an unprecedented flux of gamma rays. Onboard gamma ray detectors jumped from 100 to 40,000 counts and then off-scale in a fraction of a millisecond---first on Venera 11, then 5 seconds later on Venera 12. The detectors had not been designed for such a flood of energy and they "saturated," losing count of the gamma rays pouring through them. Eleven seconds later, more gamma rays blasted an American space probe, Helios 2, in orbit around the Sun, also knocking its detectors off scale.
A plane wavefront of gamma rays was evidently sweeping through the Solar system at the speed of light. It soon reached Venus, where the Pioneer Venus Orbiterīs gamma ray detector also went over the top. Then only 7 seconds later it reached Earth. Nobody noticed as it passed: life went on calmly beneath the protective atmosphere. It was a rainy, dreary, cold Monday morning on the U.S. East coast; chilly and clear elsewhere in the country. The lead story in U.S. newspapers concerned President Carterīs attempts to advance an Israeli-Egyptian peace treaty. (I was 4000 miles across the Atlantic Ocean then, a young student at Cambridge University.)
Meanwhile up in Earth orbit, three Vela satellites and a Soviet satellite named Prognoz 7 were swamped with a sudden flood of gamma rays. The Einstein X-ray Observatory, an orbiting X-ray telescope, also showed a strong signal. Gamma rays were diffusing copiously through the metal radiation shields surrounding its detectors.
As the wavefront passed out of the solar system, it hit one more space probe: the International Sun-Earth Explorer (ISEE) in orbit around the gravitational null or Lagrangian point of the Sun-Earth system. (A few years later this probe left the Lagrangian point, and was sent drifing through the wider solar system in an effort to study comets, at which time it was renamed the International Cometary Explorer or ICE.) The gamma-ray detector on ISEE was pointed away from the oncoming gamma rays, but they passed through the solid body of the spacecraft, partially scattered and absorbed and were still able to kick the detector up to maximum. Sixteen years later a team of Los Alamos scientists would make elaborate computer simulations of gamma rays passing through the ISEE spacecraft in an attempt to extract more information about this intense burst.
Light curve of the March 5th event, as recorded by gamma-ray detectors aboard the Venera 12 space probe. (From E.P. Mazets et al., 1979, Nature 282, p. 587.)
All the detectors showed that the burst began with a "hard pulse" of gamma rays lasting 0.2 seconds. This pulse was about 100 times more intense than any burst of cosmic gamma rays that had been detected up to that time. Nineteen years later, it still held the record, by about a factor of 10. The hard pulse saturated the detectors. It was followed by a much fainter "soft tail" of soft gamma rays (or hard X-rays), lasting over 3 minutes, steadily fading. As it faded, the soft tail also varied in intensity in something like a sine wave, but with two peaks per cycle, and with a cycle period of 8.0 s. The 8-second modulations were clearly observed by many different detectors for more than 20 cycles. Nothing like this soft tail had ever been seen by astronomers, or was seen again for 19 years.
Fourteen and a half hours later, at 1:17 A.M. E.S.T. on March 6th, another, a fainter burst came from the same spot in the sky, lasting only 1.5 seconds. In retrospect we can see that it was a normal SGR burst in all its properties. Then, a month later on April 4th and again on April 24, more SGR-type bursts came, each lasting about 0.2 second. Over the next four years, 16 SGR-type bursts were seen from this source. Then in May 1983, the bursting ceased. No bursts have been detected from this source since.
Many people suggested that the SGR-like bursts were a residual effect of the huge March 5th event, perhaps a sign that the burster was "settling" into its post-burst state. Russian astrophysicists noted that spectrum of the soft tail of the March 5th event---that is, the distribution of energies of the detected hard X-ray photons---was almost identical to the spectrum of the SGR-like bursts which followed. Thus the soft tail could be considered a "super long-duration" SGR-type event, although the hard initial pulse was unique to March 5, 1979.
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The burster is located
In the months and years after March 5, 1979, scientists analyzed data from the different spacecraft. Each detector had a clock that tagged the time on when the gamma rays first hit, to the nearest millisecond. By comparing these times from spacecraft at different places in the solar system, astronomers were able to tell at what angle the plane wavefront of gamma rays had passed through the solar system. This in turn told them where in the sky the burst came from. It took more than a year to do this accurately. The result was a huge surprise.
The source turned out to lie inside the tiny area of the sky which is covered by a "supernova remnant": the glowing cloud of hot gas left over from a massive stellar explosion. However, this particular supernova remnant (SNR), with the catalog name N49, is not in our own Milky Way galaxy. Instead, SNR N49 is in a "dwarf satellite galaxy" of the Milky Way called the Large Magellanic Cloud (LMC). The LMC is an irregular knot of stars that is prominent in the sky in the Southern Hemisphere. It is one of the nearest clumps of stars outside our galaxy, 180,000 light years from Earth. The LMC is called a "dwarf satellite galaxy" because it is a small galaxy that orbits the Milky Way.
Supernovae are common in the LMC; in fact, one was observed to go off there in February 1987---"Supernova 1987A."
Could the March 5th burster actually be much closer to us than the LMC? Almost certainly not. This would require that it just happens to have a position that overlaps with the tiny SNR in the LMC, which would be a tremendously improbable coincidence. Thus there is little doubt that the source was actually in the LMC, 180,000 light-years, or 1018 miles, away.
This was a shock. Everyone had expected that the source would be in the near galactic neighborhood, at most a few hundred light years away.
This meant that the burst actually occured 180,000 years ago, long before the dawn of history, but it took this long for the gamma rays to reach us. The "plane wavefront" passing through the solar system was actually part of an expanding sphere of radiation, 180,000 light years in radius; it only seemed flat locally because the sphereīs radius was huge compared to the size of the solar system.
The fact that the source is so far away means that the burst was enormously bright, intrinsically. At its peak the burster was shining about 10 times brighter than all the stars in our galaxy put together, or about 10 times brighter than a supernova explosion at its peak photon brightness. (Note that galactic stars and supernovae both radiate mostly optical & UV photons, whereas the March 5th burster radiated mostly gamma rays; but the energy loss rates can be compared.)
In the first two-tenths of a second, the burster radiated away as much energy as the Sun radiates in 3000 years.
There was one more tantalizing clue... The position of burster, as precisely determined using data from 7 different spacecraft, did not lie at the center of the spherical SNR, but significantly displaced toward the edge. (See the figure above.) This displacement was verified in 1991 when a faint, steady "point source" of X-rays was found at the position of the burster, allowing its position to be accurately measured. (These X-rays are evidently emitted by the burster. Astronomers call it a "point source" because its size and shape are not measured: it is so small that it is indistinguishable from a point with present X-ray telescopes.)
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March 5th Burst Theories
What caused the March 5th event? Assuming that the March 5 burster formed in the supernova which gave rise to SNR N49, as seems likely, then we can infer that....
the March 5 burster has the following properties.
The burster is probably
a neutron star, because
neutron stars are known
to form inside supernovae
(e.g., the Crab pulsar inside
the Crab SNR). A neutron star is an ultra-dense ball of neutrons, like a giant atomic nucleus floating and spinning in space. It is about 10 kilometers in radius, with a weight comparable to that of the Sun. Such a star forms when a massive, ordinary star depletes its supply of nuclear fuel. The core of the star collapses inward under its own gravity, becoming a neutron star, while the rest of the star is blown away in a supernova.
The burster is young, at least on astronomical time scales: than 10,000 years old. Astronomers can estimate the age of a SNR, that is, how long ago the supernova occured. This is done by measuring properties of the SNR, like its size and rate of expansion. The SNR containing the March 5th burster was roughly 5000 years old when the burst occurred.
The burster was born moving at a high velocity. Assuming that the burster formed in the center of the supernova explosion, as seems likely, then it must have acquired a recoil or kick velocity of about 1000 kilometers per second, in order to move it off-center during the roughly 5000 years that went by before the burst occurred. This is fast for a neutron star, but not unreasonably fast.
It is probably an isolated neutron star, i.e. not in a binary star system. Evidently, the neutron star acquired its high velocity when it formed. This means that it is probably not bound (by gravity) to orbit around another star. If it had been bound when it formed in the supernova, its high velocity would have broken it free.
The 8-second modulation seems to indicate that the star is rotating once every 8.0 seconds. This is quite slow for an isolated, young neutron star. For example, the Crab pulsar, a well-known neutron star in a young SNR, rotates once every 33 milliseconds, or 30 times per second. (When neutron stars form in stellar core collapse, shrinking suddenly by a factor of 300, they twirl up to high speeds for the same reason that an ice skater spins faster when pulling in her arms.)
The point source of X-rays indicates that the neutron star is steadily giving off energy, from some (unknown) energy source.
Nobody understood why a neutron star would have this strange set of properties, or what would cause it to burst so spectacularly.
Many theories were proposed in the 1980s, suggesting, for example, that the March 5th event was due to a small planet or a large asteroid slamming into a neutron star, or a "phase transition" in the core of a neutron star (i.e., the neutron starīs core somehow abruptly changed its state as it cooled, like water does when it freezes, releasing energy in the process), or even more speculative suggestions involving hypothetical new objects, such as "a quark nugget falling onto a strange quark star." Most of these ideas accounted for only a limited subset of the known facts. Almost none of them attracted many believers, or were the subject of more than one research paper.
It was particularly difficult for theorists to account for the enormous gamma-ray brightness of the hard initial pulse of the March 5th event. If you try to power this from some material falling onto a neutron star (e.g., from a planet or asteroid) then the pressure associated with the outflowing gamma rays itself halts the inflow, and cuts off the energy supply. But if you try to power it from a source deep inside the neutron star, like a phase transition, then it is hard to get all the energy out quickly and completely enough in the form of gamma rays. |
| noted and wanrned
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
That was a lot of words.
Hereīs the short story.
Earth is now being īhitī by itīs cosmic shock wave from the south.
Connect all the dots people.
The government knows this and is QUITE UNSHURE what will transpire when itīs finally all over.
I was here before and will be censored if I post a thread in a split second if I spill there speculations.
-godspeed- |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
what consequences? |
| Proof
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
what consequences?
 |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
please help us connect the dots, I donīt have a clue |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
More doomsday fantasies from the woo-woos. Their lives must be pretty bleak--else why would they be so eager for the world to end? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Earth is now being īhitī by itīs cosmic shock wave from the south. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
How far away from the earth is the 1987 Nebula? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Tell us what you know, Scarlet. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
A site that I just read said that to hurt life in this solar system, the supernova would have to be closer than 100 light years. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Since the light from the supernova reached the Solar System 26 years ago, it should be obvious even to Scarlet Witch that, once again, we have escaped annihilation. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
What "cosmic shock wave from the south"??
Thereīs no such thing. How about a link if you think there is? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
<>
This poster doesnīt realise just how braindead he is. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
debris cloud....something was mentioned about this in the late 1970īs than they started talking about "Global Warming." It is interesting to note that the "Galelio" probe was launched about the same time, if I am not mistaken and we all know that it was allowed to collide with Jupiter just last year I think it was? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Sorry I meant to say the year 2003. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
all this info is talked about in detail on the old AB threads, you will find them at cyberspace, probably the archives. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
ac give us the link to cyberspace website please. thank you. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
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| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
what has it got to do with the Temple 1 comet? |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
NOTHING |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
hmmm....here comes the debunkers and spooks, now I know that it has something to do with it and this thread is on to something without a doubt. |
| Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
Most GLP threads are coherent, even if they are insane. But for the life of me I canīt figure out what the woo-woos are driving at this time. |
| Anonymous Coward
12/8/2005 10:12 AM | | Anonymous Coward
12/8/2005 10:12 AM | | Re: Supernova N49, March 5th, 1979, magnetar, gamma-ray burst event....... | Quote |
n & w, we are waiting for the 3 speculations. |
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