Brightest Explosion Ever Recorded
from
RedNovaNews Website
2005/02/18
NASA -- Scientists have detected a flash of light from across
the Galaxy so powerful that it bounced off the Moon and lit up
the Earth’s upper atmosphere. The flash was brighter than
anything ever detected from beyond our Solar System and lasted
over a tenth of a second.
NASA and European satellites and many radio telescopes detected
the flash and its aftermath on December 27, 2004. Two science
teams report about this event at a special press event today at
NASA headquarters. A multitude of papers are planned for
publication.
The scientists said the light came from a "giant flare" on the
surface of an exotic neutron star, called a magnetar. The
apparent magnitude was brighter than a full moon and all
historical star explosions. The light was brightest in the
gamma-ray energy range, far more energetic than visible light or
X-rays and invisible to our eyes.
Such a close and powerful eruption raises the question of
whether an even larger influx of gamma rays, disturbing the
atmosphere, was responsible for one of the mass extinctions
known to have occurred on Earth hundreds of millions of years
ago. Also, if giant flares can be this powerful, then some
gamma-ray bursts (thought to be very distant black-hole-forming
star explosions) could actually be from neutron star eruptions
in nearby galaxies.
NASA’s newly launched Swift satellite and the NSF-funded
Very
Large Array (VLA) were two of many observatories that observed
the event, arising from neutron star SGR 1806-20, about 50,000
light years from Earth in the constellation Sagittarius.
"This might be a once-in-a-lifetime event for astronomers, as
well as for the neutron star," said Dr. David Palmer of Los
Alamos National Laboratory, lead author on a paper describing
the Swift observation. "We know of only two other giant flares
in the past 35 years, and this December event was one hundred
times more powerful."
Dr. Bryan Gaensler of the Harvard-Smithsonian Center for
Astrophysics in Cambridge, Mass., is lead author on a report
describing the VLA observation, which tracked the ejected
material as it flew out into interstellar space. Other key
scientific teams are associated with radio telescopes in
Australia, The Netherlands, United Kingdom, India and the United
States, as well as with NASA’s High Energy Solar Spectroscopic
Imager (RHESSI).
A neutron star is the core remains of a star once several times
more massive than our Sun. When such stars deplete their nuclear
fuel, they explode -- an event called a supernova. The remaining
core is dense, fast-spinning, highly magnetic, and only about 15
miles in diameter. Millions of neutron stars fill our Milky Way
galaxy.
Scientists have discovered about a dozen ultrahigh-magnetic
neutron stars, called magnetars. The magnetic field around a
magnetar is about 1,000 trillion gauss, strong enough to strip
information from a credit card at a distance halfway to the
moon. (Ordinary neutron stars measure a mere trillion gauss; the
Earth’s magnetic field is about 0.5 gauss.)
Four of these magnetars are also called soft gamma repeaters, or
SGRs, because they flare up randomly and release gamma rays.
Such episodes release about 10^30 to 10^35 watts for about a
second, or up to millions of times more energy than our Sun. For
a tenth of a second, the giant flare on SGR 1806-20 unleashed
energy at a rate of about 10^40 watts. The total energy produced
was more than the Sun emits in 150,000 years.
"The next biggest flare ever seen from any soft gamma repeater
was peanuts compared to this incredible December 27 event," said
Gaensler. "Had this happened within 10 light years of us, it
would have severely damaged our atmosphere. Fortunately, all the
magnetars we know of are much farther away than this."
A scientific debate raged in the 1980s over whether gamma-ray
bursts were star explosions from beyond our Galaxy or eruptions
on nearby neutron stars. By the late 1990s it became clear that
gamma-ray bursts did indeed originate very far away and that
SGRs were a different phenomenon. But the extraordinary giant
flare on SGR 1806-20 reopens the debate, according to Dr. Chryssa Kouveliotou of NASA Marshall Space Flight Center, who
took part in both the Swift and VLA analysis.
A sizeable percentage of "short" gamma-ray bursts, less than two
seconds, could be SGR flares, she said. These would come from
galaxies within about a 100 million light years from Earth.
(Long gamma-ray bursts appear to be black-hole-forming star
explosions billions of light years away.)
"An answer to the ’short’ gamma-ray burst mystery could come any
day now that Swift is in orbit", said Swift lead scientist
Neil Gehrels. "Swift saw this event after only about a month on the
job."
Scientists around the world have been following the December 27
event. RHESSI detected gamma rays and X-rays from the flare.
Drs. Kevin Hurley and Steven Boggs of the University of
California, Berkeley, are leading the effort to analyze these
data. Dr. Robert Duncan of the University of Texas at Austin and
Dr. Christopher Thompson at the Canadian Institute for
Theoretical Astrophysics (University of Toronto) are the leading
experts on magnetars, and they are investigating the "short
duration" gamma-ray burst relationship.
Brian Cameron, a graduate student at Caltech under the tutorage
of Prof. Shri Kulkarni, leads a second scientific paper based on
VLA data. Amateur astronomers detected the disturbance in the
Earth’s ionosphere and relayed this information through the
American Association of Variable Star Observers.
|
Gamma Ray
flare expanding from SGR 1806-20 and impacting Earth’s
atmosphere. Credit: NASA |
|
An artist
conception of the SGR 1806-20 magnetar including
magnetic field lines. Credit: NASA |
|
SGR-1806 is
located about 50,000 light years away from Earth in the
constellation Sagittarius. Credit: NASA |
|
Swift is a
first-of-its-kind multi-wavelength observatory dedicated
to the study of gamma ray burst (GRB) science. Credit:
NASA |
|
High
resolution, wide-field image of the area around
SGR1806-20 as seen in radio wavelength. Credit: NASA |
Videos and Animations
1) Artist conception of the December 27, 2004 gamma ray flare
expanding from SGR 1806-20 and impacting Earth’s atmosphere.
Click here to watch video.
2) An artist conception of the SGR 1806-20 magnetar including
magnetic field lines. After the initial flash, smaller
pulsations in the data suggest hot spots on the rotating
magnetar’s surface. The data also shows no change in the
magentar’s rotation after the initial flash.
Click here to watch
video.
3) Radio data shows a very active area around SGR1806-20. The
Very Large Array radio telescope observed ejected material from
this Magnetar as it flew out into interstellar space. These
observations in the radio wavelength start about 7 days after
the flare and continue for 20 days. They show SGR1806-20 dimming
in the radio spectrum.
Click here to watch video.
4) SGR-1806 is an ultra-magnetic neutron star, called a magnetar,
located about 50,000 light years away from Earth in the
constellation Sagittarius.
Click here to watch video.
5) Swift is a first-of-its-kind multi-wavelength observatory
dedicated to the study of gamma ray burst (GRB) science. Its
three instruments will work together to observe GRBs and
afterglows in the gamma ray, X-ray, ultraviolet, and optical
wavebands. Swift is designed to solve the 35-year-old mystery of
the origin of gamma-ray bursts. Scientists believe GRB are the
birth cries of black holes.
Click here to watch video.
6) NASA’s Swift satellite was successfully launched Saturday,
November 20, 2004 from the Cape Canaveral Air Force Station,
Fla.
Click here to watch video.
Other observatories and scientific representatives include:
Additional information about magentars and
soft gamma ray
repeaters can be found at Dr. Robert Duncan’s web site located
at the University of Texas at Austin:
http://solomon.as.utexas.edu/~duncan/magnetar.html
Huge explosion traced to exotic star
by Jim Giles
News - Published online: 18 February
2005
from
Nature Website
Astronomers pinpoint source of unprecedented radiation surge.
The rotating, highly-magnetized neutron star undergoing a
’quake’ at its surface. Click here to see animation.
A cataclysmic ’starquake’ is thought to have caused a flare of
radiation that ripped past the Earth on 27 December, battering
instruments on satellites and lighting up our atmosphere.
Scientists say this is the biggest blast of gamma and
X-rays
they have ever observed in our corner of the Universe. They
believe the flare came from a bizarre object just 20 kilometers
wide on the other side of the Galaxy.
"This is a once-in-a-lifetime event," says
Rob Fender of
Southampton University, UK, one of the researchers studying data
on the flare. "The object released more energy in a tenth of a
second than the Sun emits in 100,000 years."
Data from satellites and ground-based telescopes have pinpointed
the origin of the burst as SGR 1806-20, a ’magnetar’ around
50,000 light-years away in the constellation of Sagittarius.
Magnetars are extremely dense, small stars with magnetic fields
at least a thousand trillion times stronger than the Earth’s.
They are a type of neutron star, the compact remnant of a
collapsed sun.
Huge
explosion traced to exotic star
Astronomically speaking, this was in our backyard.
Bryan Gaensler
Harvard-Smithsonian Center for Astrophysics
from
Nature Website
The flare may have been caused by a quake on the surface of SGR
1806-20, suggest researchers. The quake would have disturbed the
star’s magnetic field, creating an explosion that was the
brightest ever detected beyond our Solar System.
It is possible that similar flares have been misinterpreted in
the past. Analogous gamma ray bursts have been detected, but
they were assumed to come from very distant objects beyond our
galaxy.
A satellite launched last November is ideally positioned to
resolve the issue. NASA’s Swift Gamma Ray Burst Mission is
designed to locate and measure bursts. "Answers to these
questions could come any day now that Swift is in orbit," says
Neil Gehrels of NASA’s Goddard Space Flight Center in Maryland.
Safe distance
Fortunately for life on Earth, the nearest known magnetar is
about 13,000 light years away - too far for any future burst to
damage the planet. The radiation burst from a closer explosion
could, for example, wipe out the ozone layer.
"Astronomically speaking, this was in our backyard," says Bryan
Gaensler of the Harvard-Smithsonian Center for Astrophysics in
Cambridge, Massachusetts, and an author of a paper about the
burst that has been accepted for publication in Nature. "If it
were in our living room, we’d be in big trouble."
Blast Affected Earth From Halfway Across The Milky Way
Cambridge MA (SPX) Feb 21, 2005
from
SpaceDaily Website
Forget "Independence Day" or "War of the Worlds." A monstrous
cosmic explosion last December showed that the earth is in more
danger from real-life space threats than from hypothetical alien
invasions.
The gamma-ray flare, which briefly outshone the full moon,
occurred within the Milky Way galaxy. Even at a distance of
50,000 light-years, the flare disrupted the earth’s ionosphere.
If such a blast happened within 10 light-years of the earth, it
would destroy the much of the ozone layer, causing extinctions
due to increased radiation.
"Astronomically speaking, this explosion happened in our
backyard. If it were in our living room, we’d be in big
trouble!"
Said Bryan Gaensler (Harvard-Smithsonian Center for
Astrophysics), lead author on a paper describing radio
observations of the event.
Gaensler headed one of two teams reporting on this eruption at a
special press event today at NASA headquarters. A multitude of
papers are planned for publication.
The giant flare detected on December 27, 2004, came from an
isolated, exotic neutron star within the Milky Way. The flare
was more powerful than any blast previously seen in our galaxy.
"This might be a once-in-a-lifetime event for astronomers, as
well as for a neutron star," said David Palmer of Los Alamos
National Laboratory, lead author on a paper describing
space-based observations of the burst.
"We know of only two other giant flares in the past 35 years,
and this December event was one hundred times more powerful."
NASA’s newly launched Swift satellite and the NSF-funded Very
Large Array (VLA) were two of many observatories that observed
the event, arising from neutron star SGR 1806-20, about 50,000
light years from Earth in the constellation Sagittarius.
Neutron stars form from collapsed stars. They are dense,
fast-spinning, highly magnetic, and only about 15 miles in
diameter. SGR 1806-20 is a unique neutron star called a magnetar,
with an ultra-strong magnetic field capable of stripping
information from a credit card at a distance halfway to the
Moon. Only about 10 magnetars are known among the many neutrons
stars in the Milky Way.
"Fortunately, there are no magnetars anywhere near the earth. An
explosion like this within a few trillion miles could really
ruin our day," said graduate student Yosi Gelfand (CfA), a
co-author on one of the papers.
The magnetar’s powerful magnetic field generated the gamma-ray
flare in a violent process known as magnetic reconnection, which
releases huge amounts of energy. The same process on a much
smaller scale creates solar flares.
"This eruption was a super-super-super solar flare in terms of
energy released," said Gaensler.
Using the VLA and three other radio telescopes,
Gaensler and his
team detected material ejected by the blast at a velocity
three-tenths the speed of light. The extreme speed, combined
with the close-up view, yielded changes in a matter of days.
Spotting such a nearby gamma-ray flare offered scientists an
incredible advantage, allowing them to study it in more detail
than ever before.
"We can see the structure of the flare’s
aftermath, and we can watch it change from day to day. That
combination is completely unprecedented," said Gaensler.
Headquartered in Cambridge, Mass., the Harvard-Smithsonian
Center for Astrophysics (CfA) is a joint collaboration between
the Smithsonian Astrophysical Observatory and the Harvard
College Observatory. CfA scientists, organized into six research
divisions, study the origin, evolution and ultimate fate of the
universe.
Distant explosion breaks brightness records
by Maggie McKee
19:00 18 February 2005
from
NewScientist Website
Several dozen satellites around Earth, and one orbiting Mars,
detected a flash of high-energy photons - known as gamma rays -
on 27 December 2004. The 0.25-second flash was so bright it
overwhelmed the detectors on many satellites - making an energy
measurement impossible - and disrupted some radio communication
on Earth.
"It was so bright, it came right through the body of the Swift
satellite, even though Swift wasn’t pointed at the object," says
John Nousek, mission director for NASA’s Swift spacecraft -
launched especially to detect gamma-ray bursts (GRBs) - at
Pennsylvania State University, US.
The brief flash was followed by a fainter afterglow of gamma
rays lasting for about 500 seconds, which showed a recurring
signal every 7.5 seconds. That signal led scientists using
Europe’s INTEGRAL spacecraft to trace the source of the "superflare"
to a dead star - called a neutron star - known to spin at that
rate. Measurements of the distance to the star - called SGR
1806-20, range from 30,000 to 50,000 light years from Earth.
That relatively small distance, coupled with an accurate energy
measurement by NASA’s RHESSI satellite, means the explosion was
not as powerful - at source - as more distant bursts linked with
black holes. Nevertheless, it "may have sterilized any planets
within a few light years of it", says Rob Fender, an astronomer
at Southampton University, UK, who is studying the lingering
radio emission from the flare. "This may be a once-in-a-lifetime
event both for astronomers and for the neutron star itself."
Clean credit card
But Christopher Thompson, an astrophysicist at the Canadian
Institute for Theoretical Physics, says that may not be so. The
neutron star in question is rare magnetar, with a magnetic field
so strong it could wipe a credit card clean from a distance of
160,000 kilometers. And this magnetar is even rarer yet, one of
three "soft gamma repeaters" (SGRs) in the Milky Way.
SGRs tend to release low-energy flares of gamma rays
sporadically, but more energetic bursts have been observed twice
before - in 1998 and 1979. But the energy in the initial
0.25-second burst from the most recent flare was 100 times that
of the two previous superflares.
But Thompson, who worked on the most accepted magnetar model,
says:
"I wasn’t shocked at the energy it was putting out. The
total energy implied by the models is enough to power a dozen or
more of these events in the life of one magnetar."
Superflares may occur when tightly wrapped magnetic fields
inside the magnetar start to "untwist". This briefly rips loose
some magnetic fields outside the star, releasing a "fireball" of
particles, and light that astronomers see as a bright flash of
gamma rays.
Extreme distances
If this flare had been even farther away - up to 100 million
light years or so - it would have looked "indistinguishable"
from a short GRB - a cosmic phenomenon that has baffled
astronomers for years. Short GRBs are blasts of high-energy
gamma rays that last less than two seconds. Astronomers are
unsure of their cause but think they have a different origin
than "long" GRBs - lasting for several seconds or minutes -
which are thought to be created during the birth of black holes.
This latest observation leads David Palmer, a Swift team member
at Los Alamos National Laboratory in New Mexico, US, to say:
"I’m fairly confident that soft gamma repeaters account for at
least some short gamma-ray bursts."
Neil Gehrels, principal investigator for Swift at NASA, says
Swift should be able to help settle the debate about short GRBs.
Swift will study both SGRs and short GRBs, having the capability
to quickly respond to short GRBs in order to locate them in
space.
But he laments: "It’s very unlikely we’re going to see another
one of these supergiant flares."
Related Articles
•
Massive exploding stars create rare magnetars
05 February 2005
•
Swift mission sees its first gamma ray bursts
07 January 2005
•
Superbright gamma ray burst may be closest ever
04 April 2003
Weblinks
•
Swift, NASA
•
INTEGRAL, ESA
•
RHESSI, NASA
Monster star burst was brighter than full Moon: astronomers
AFP
Fri Feb 18, 2005 2:40 pm
from
Able2Know Website
PARIS (AFP) - Stunned astronomers described the greatest cosmic
explosion ever monitored -- a star burst from the other side of
the galaxy that was briefly brighter than the full Moon and
swamped satellites and telescopes.
The high-radiation flash, detected last December 27, caused no
harm to Earth but would have literally fried the planet had it
occurred within a few light years of home.
Normally reserved skywatchers struggled for superlatives.
"This is a once-in-a-lifetime event," said
Rob Fender of
Britain’s Southampton University.
"We have observed an object only 20 kilometers (12 miles)
across, on the other side of our galaxy, releasing more energy
in a 10th of a second than the Sun emits in 100,000 years."
"It was the mother of all magnetic flares -- a true monster,"
said Kevin Hurley, a research physicist at the University of
California at Berkeley.
Bryan Gaensler of the United States’ Harvard-Smithsonian Center
for Astrophysics, described the burst as,
"maybe a once per
century or once per millennium event in our galaxy.
"Astronomically speaking, this explosion happened in our
backyard. If it were in our living room, we’d be in big
trouble."
The blast was caused by an eruption on the surface of a known,
exotic kind of neutron star called SGR 1806-20, located about
50,000 light years from Earth in the constellation of
Sagittarius and about three billion times farther from us than
the Sun.
A neutron star is the remnant of a very large star near the end
of its life -- a tiny, extraordinarily dense core with a
powerful magnetic field, spinning swiftly on its axis.
When these ancient star cores finally run out of fuel, they
collapse in on themselves and explode as a supernova.
There are millions of neutron stars in the Milky Way but, so
far, only a dozen have been found to be "magnetars": neutron
stars with an ultra-powerful magnetic field.
Magnetars have have a magnetic field measuring about 1,000
trillion gauss, hundreds of times more powerful than that of any
other object in the Universe.
To give an idea of this in earthly terms, the field is so
powerful that it could strip the data off a credit card at a
distance of 200,000 kilometers (120,000 miles).
SGR 1806-20 is an even rarer bird. It is one of only four known
"soft gamma repeater" (SGR) magnetars, so called because they
flare up randomly and release gamma rays in a mammoth burst.
Why this happens is unknown. One theory is that the energy
release comes from magnetic fields which wrestle and overlap
because of the star’s spin and then snap back and reconnect,
creating a "starquake" rather like the competing faults that
cause an earthquake.
What is sure, though, is that the outpouring of energy is
massive.
The SGR 1806-20 spewed out about 10,000 trillion trillion watts,
or about 100 times brighter than any of the several "giant
flares" that have been previously recorded.
Despite this energy loss, the strange star did not even pause,
Britain’s Royal Astronomical Society (RAS) said.
"SGR 1806-20 spins once in only 7.5 seconds. Amazingly, the
December 27 event did not cause any slowing of its spin rate, as
would be expected," the RAS said.
The flare, detected by satellites and telescopes operated by
NASA (news - web sites) and Europe, was so powerful that it
bounced off the Moon and lit up the Earth’s upper atmosphere.
For over a tenth of the second, it was actually brighter than a
full Moon, and briefly overwhelmed delicate sensors, RAS said.
Two science teams, formed by observations provided by 20
institutes around the world, will report on the blast in a
forthcoming issue of the British weekly journal Nature.
Many questions will be thrown up by the event, including the
intriguing speculation that the dinosaurs may have been wiped
out by a similar, closer gamma-ray explosion 65 million years
ago, and not by climate change inflicted by an asteroid impact.
"Had this happened within 10 light years of us, it would have
severely damaged our atmosphere and possibly have triggered a
mass extinction," said lead-author Gaensler.
The good news, he noted, is that the nearest known
magnetar to
Earth, 1E 2259+586, is about 13,000 light years away.
Magnetar flare blitzed Earth Dec. 27, could solve cosmic
mysteries
Co-authors with Hurley, Boggs, Duncan and
Thompson were D. M.
Smith of the UC Santa Cruz physics department, RHESSI and
Wind principal investigator and Space Sciences Laboratory
Director Robert Lin, and teams of U.S., Swiss, Russian,
and German scientists
This information is co-released with The University of
California, Berkeley, and co-insides with a NASA Space Science
Update
18 February 2005
from
McDonaldObservatory Website
Austin, Texas
— Astronomers around the world recorded late last
year a powerful explosion of high-energy X-rays and gamma rays —
a split-second flash from the other side of our galaxy that was
strong enough to affect the Earth’s atmosphere. The flash,
called a soft gamma repeater flare, reached Earth on Dec. 27 and
was detected by at least 15 satellites and spacecraft between
Earth and Saturn, swamping most of their detectors.
Thought to be a mighty cataclysm in a super-dense, highly
magnetized star called a magnetar, it emitted as much energy in
two-tenths of a second as the sun gives off in 250,000 years.
Robert C. Duncan of the University of Texas at Austin originally
proposed and developed the magnetar theory, along with
Christopher Thompson of the Canadian Institute of Theoretical
Astrophysics.
"This is a key event for understanding magnetars,"
Duncan said.
Its intrinsic power was a thousand times greater than the power
of all other stars in the galaxy put together, and at least 100
times the power of any previous magnetar outburst in our galaxy.
It was ten thousand times brighter than the brightest supernova.
Duncan and Thompson worked with Kevin Hurley, a research
physicist at UC Berkeley who leads a major international team
studying the event, to understand the immense power of the Dec.
27 flare. "It was the mother of all magnetic flares - a true
monster," Hurley said.
The team’s observations and analysis are summarized in a paper
that has been submitted for publication in the journal Nature.
"Soft gamma repeater" bursts — pinpoint flashes of highly
energetic X-rays and low-energy (soft) gamma rays coming
repeatedly from one place in the sky — were first noticed in
1979 and remained a mystery until Duncan and Thompson proposed
in 1992 that they originate from magnetically powered neutron
stars, or magnetars. Formed by the collapsing core of a star
throwing off its outer layers in a supernova explosion, neutron
stars are extremely dense, with more mass than in the Sun packed
into a ball about 10 miles across. Many neutron stars spin
rapidly. These spinning neutron stars, some rotating a thousand
times a second, signal their presence by the emission of pulsed
radio waves, and are called pulsars.
According to Duncan, magnetars are a special kind of neutron
star. They are born rotating very quickly, which causes their
magnetic fields to get amplified. But after a few thousand
years, their intense magnetic field slows their spin to a more
moderate period of one rotation every few seconds. The magnetic
fields both inside and outside the star twist, however, and
according to the theory these intense fields can stress and move
the crust much like shearing along the San Andreas Fault. These
magnetic fields are a quadrillion — a million billion — times
stronger than the field that deflects compass needles at the
Earth’s surface.
The shear moves the crust around and the magnetic fields are
tied to the crust, generating twists in the magnetic field that
can sometimes break and reconnect in a process that sends
trapped positrons and electrons flying out from the star,
annihilating each other in a gigantic explosion of hard gamma
rays.
The flare observed Dec. 27 originated about 50,000 light years
away in the constellation Sagittarius, which means that the magnetar sits directly opposite the center of our galaxy from
the Earth in the disk of the Milky Way Galaxy.
As the radiation stormed through our solar system, it blitzed at
least 15 spacecraft, knocking their instruments off-scale
whether or not they were pointing in the magnetar’s direction.
One Russian satellite, Coronas-F, detected gamma rays that had
bounced off the Moon.
The flare also ripped atoms apart, ionizing them, in much of the
Earth’s ionosphere for five minutes, to a deeper level than even
the biggest solar flares do, an effect noticed via its effect on
long-wavelength radio communications. Such events are unlikely
to pose a danger to the Earth because the chances that one would
be close enough to the Earth to cause serious disruption are
exceedingly small.
Hurley and his team combined information from many spacecraft,
including neutron and gamma-ray detectors aboard Mars Odyssey
and many near-Earth satellites, in order to localize it to a
spot well-known to astronomers: a magnetar known as SGR 1806-20.
This position was accurately confirmed by radio astronomers at
the Very Large Array in Socorro, N.M., who studied the fading
radio afterglow of the event and obtained important information
about the explosion.
The tremendous power of the event has suggested a novel solution
to a long-standing mystery — the origins of a strange phenomenon
known as "Short-Duration Gamma Ray Bursts." Hundreds of brief,
mysterious flashes of high-energy radiation from deepest space,
lasting less than two seconds, have been measured and recorded
over decades, but nobody knew what they were.
The similarity between the Dec. 27 burst and these
short-duration bursts lies in the brief spike of hard gamma rays
that arrives first and carries almost all the energy. In the
recent burst, for example, the hard spike lasted only two-tenths
of a second. This was followed by a "tail" of X-rays that lasted
over six minutes. As the tail faded, its brightness oscillated
on a 7.56 second cycle, the known rotation period of the
magnetar.
According to Duncan and Thompson’s theory, the oscillating X-ray
tail that followed was due to a residue of electrons, positrons
and gamma-rays trapped in the magnetar’s magnetic field. Such a
hot "trapped fireball" shrinks and evaporates over minutes, as
electrons and positrons annihilate. The measurements of Hurley’s
team corroborate this picture. The tail’s brightness appears to
oscillate because the fireball is stuck to the surface of the
rotating star by the magnetic field, so it rotates with the star
like a lighthouse beacon.
Duncan and his team argue that the hard initial spike of these
giant flares is so bright that it can be detected from very far
away, meaning that some of the short flares we see are from
other galaxies, though the soft X-ray tails are too faint to be
seen.
Duncan and his collaborators predict that if a magnetar flares
as brightly as the December 27 event within 100 million
light-years of Earth, astronomers should be able to detect it.
Texas astronomers John Scalo and Sheila Kannappan helped
Duncan
estimate the rate at which such distant flares might be seen.
They estimated that of order 40% of the short bursts previously
observed could have been such magnetar bursts. There is a good
probability that the newly-launched Swift satellite will see a magnetar burst once a month.
Launched in November 2004 and gathering data only since January,
Swift is designed to automatically turn its X-ray telescope
toward a burst in order to accurately pin down its position.
Duncan’s team estimates that Swift will spot an abundance of
magnetars lurking in other galaxies. In some cases, Swift’s
X-ray telescope may even catch the oscillating tail and measure
the rotation period of the faraway star.
"Swift will open up a new field of astronomy: the study of
extragalactic magnetars," Duncan said.
Huge ’star-quake’ rocks Milky Way
from
12thArmonic Website
It turns out that the 26th and 27th of December were not only
turbulent for our planet, but turbulent for our galaxy too. The
explosion took place in the constellation of Sagittarius. I’m
very grateful to fixed star expert Diana K Rosenberg for
calculating the position and time of the explosion, which in
astrological tropical zodiac terms occurred at 01CAP28; LAT 3N
25 53; DECL 19S20; RA 18 06 18. It occurred Dec 27, 2004, at
21:30:26 UT.
BBC
- Astronomers say they have been stunned by the amount of
energy released in a star explosion on the far side of our
galaxy, 50,000 light-years away.
The flash of radiation on 27 December was so powerful that it
bounced off the Moon and lit up the Earth’s atmosphere.
The blast occurred on the surface of an exotic kind of star - a
super-magnetic neutron star called SGR 1806-20.
If the explosion had been within just 10 light-years, Earth
could have suffered a mass extinction, it is said.
"We figure that it’s probably the biggest explosion observed by
humans within our galaxy since Johannes Kepler saw his supernova
in 1604," Dr Rob Fender, of Southampton University, UK, told the
BBC News website.
One calculation has the giant flare on
SGR 1806-20 unleashing
about 10,000 trillion trillion trillion watts.
"This is a once-in-a-lifetime event. We have observed an object
only 20km across, on the other side of our galaxy, releasing
more energy in a 10th of a second than the Sun emits in 100,000
years," said Dr Fender.
VLA Probes Secrets of Mysterious Magnetar
February 18, 2005
from
NationalScienceFoundation
Website
|
This graphic
illustrates the VLA measurements of the exanding
fireball from the Dec. 27, 2004, outburst of the
magnetar SGR 1806-20. Each color indicates the observed
size of the fireball at a different time. The sequence
covers roughly three weeks of VLA observing. The outline
of the fireball in each case is not an actual image, but
rather a "best-fit" model of the shape that best matches
the data from the VLA.
Credit: G.B. Taylor, NRAO/AUI/NSF |
A giant flash of energy from a supermagnetic neutron star
thousands of light-years from Earth may shed a whole new light
on scientists’ understanding of such mysterious "magnetars" and
of gamma-ray bursts. In the nearly two months since the blast,
the National Science Foundation’s Very Large Array (VLA)
telescope has produced a wealth of surprising information about
the event, and "the show goes on," with continuing observations.
The blast from an object named SGR 1806-20 came on Dec. 27,
2004, and was first detected by orbiting gamma-ray and X-ray
telescopes. It was the brightest outburst ever seen coming from
an object beyond our own solar system, and its energy
overpowered most orbiting telescopes. The burst of gamma rays
and X-rays even disturbed the Earth’s ionosphere, causing a
sudden disruption in some radio communications.
While the intensely bright gamma ray burst faded in a matter of
minutes, the VLA and other radio telescopes have been tracking
the explosion’s "afterglow" for weeks, providing most of the
data astronomers need to figure out the physics of the blast.
A magnetar is a superdense neutron star with a magnetic field
thousands of trillions of times more intense than that of the
Earth. Scientists believe that SGR 1806-20’s giant burst of
energy was somehow triggered by a "starquake" in the neutron
star’s crust that caused a catastrophic disruption in the
magnetar’s magnetic field. The magnetic disruption generated the
huge burst of gamma rays and "boiled off" particles from the
star’s surface into a rapidly expanding fireball that continues
to emit radio waves for weeks or months.
The VLA first observed SGR 1806-20 on Jan. 3, and has been
joined by other radio telescopes in Australia, the Netherlands,
and India. Scientific papers prepared for publication based on
the first month’s radio observations report a number of key
discoveries about the object. Scientists using the VLA have
found:
• The fireball of radio-emitting material is expanding at
roughly one-third the speed of light.
• The expanding fireball is elongated, and may change its shape
quickly.
• Alignment of the radio waves (polarization) confirms that the
fireball is not spherical.
• The flare emitted an amount of energy that represents a
significant fraction of the total energy stored in the
magnetar’s magnetic field.
Of the dozen or so magnetars known to astronomers, only one
other has been seen to experience a giant outburst. In 1998, SGR
1900+14 put out a blast similar in many respects to SGR
1806-20’s, but much weaker.
National Radio Astronomy Observatory (NRAO) astronomer Dale
Frail observed the 1998 outburst and has been watching SGR
1806-20 for a decade. Both magnetars are part of the small group
of objects called soft gamma-ray repeaters, because they
repeatedly experience much weaker outbursts of gamma rays. In
early January, he was hosting a visiting college student while
processing the first VLA data from SGR 1806-20’s giant outburst.
"I literally could not believe what I was looking at,"
Frail
said. "Immediately I could see that this flare was 100 times
stronger than the 1998 flare, and 10,000 times brighter than
anything this object had done before."
"I couldn’t stay in my chair, and this student got to see a
real, live astronomer acting like an excited little kid,"
Frail
said.
The excitement isn’t over, either. "The show goes on and we
continue to observe this thing and continue to get surprises,"
said Greg Taylor, an astronomer for NRAO and the Kavli Institute
of Particle Astrophysics and Cosmology in Stanford, Calif..
One VLA measurement may cause difficulties for scientists trying
to fit SGR 1806-20 into a larger picture of gamma ray bursts (GRBs).
GRBs, seen regularly from throughout the universe, come in two
main types--very short bursts and longer ones. The longer ones
are generally believed to result when a massive star collapses
into a black hole, rather than into a neutron star as in a
supernova explosion. The strength and short duration of SGR
1806-20’s December outburst has led some astronomers to
speculate that a similar event could be seen out to a
considerable distance from Earth. That means, they say, that
magnetars may be the source of the short-period GRBs.
That interpretation is based to some extent on a previous
measurement that indicates SGR 1806-20 is nearly 50,000
light-years from Earth. One team of observers, however, analyzed
the radio emission from SGR 1806-20 and found evidence that the
magnetar is only about 30,000 light-years distant. The
difference, they say, reduces the likelihood that SGR 1806-20
could be a parallel for short-period GRBs.
In any case, the wealth of information astronomers have gathered
about the tremendous December blast makes it an extremely
important event for understanding magnetars and GRBs.
Continuing Earth Changes Cripple American Submarine and Pose New
Dangers for the American Continents
by Sorcha Faal, and as reported to her Russian Subscribers
January 10, 2005
from
WhatDoesItMean Website
Continued energy surges, and as yet still unexplained by Western
scientists, continue to bombard the earth’s Southern Hemispheric
Regions this morning causing many widespread and anomalous
events throughout the world and affecting all of its peoples.
Western media sources are presently reporting the dire
circumstances surrounding the United States Los Angeles Class
Nuclear Submarine San Francisco and the latest reports are
saying that one crewman has died and ‘23 other crew members are
being treated aboard for injuries including broken bones,
bruises and lacerations’.
The BBC also reports in this article that,
“The US Navy said it
did not know what the vessel had struck and was investigating
severe damage to the outside of the submarine.”
Not being reported by the Western media though is that the USS
San Francisco (SSN 711) is part of the United States Navy’s
Pacific Fleet, and a part of what is known as Submarine Squadron
Fifteen based out of the US Territory of Guam, located in the
Mariana Islands Region of the Pacific Ocean.
The significance of this lies in the eruption on Anatahan
Island, a part of the Mariana Islands and in the ‘patrol zone’
of the USS San Francisco.
As related to us by one Russian Naval Official,
“Imagine you
walking around your house at night with the lights off and
someone had re-arranged the furniture, make no mistake about it,
the American submariners ‘know’ their courses too well and are
too highly trained for this to happen suddenly. Some extreme
geologic ‘change’ had to have happened for this accident to
occur.”
Could this ‘extreme geologic change’ have been this eruption?
As reported in the Western media regarding this event we hear,
“The volcano’s activity intensified beginning Tuesday and
Wednesday last week after months of extremely low seismic
activities, which followed the second batch of eruptions from
April to June last year. The volcano on Anatahan first erupted
after centuries of dormancy on May 10, 2003, with ash plume
rising to more than 30,000 feet.”
We are also continuing to receive reports of meteor fireballs
entering the earth’s atmosphere. Yesterday another such sighting
was reported as occurring in the United States region of Alaska,
and where it is said,
“It streaked quickly from the west to the
east in a steep downward arc, and soon wasn’t visible behind the
mountains.”
More information also continues to be received by us also
relating to my December 28, 2004 report, Evidence for Sumatra
9.0 Quake Leans towards Meteorite Strike.
In one research report by the United States National Geophysical
Data Center (NGDC) it clearly states, and in apparent
contradiction to the known facts about The Great Tsunami of
2004, that,
“In the Indian Ocean, however, the Indo-Australian
plate is being subducted beneath the Eurasian plate at its east
margin. Therefore, most tsunamis generated in this area are
propagated toward the southwest shores of Java and Sumatra,
rather than into the Indian Ocean.”
As recent events have occurred however we know this not to be
the case due to the fact that the waves propagated out from a
‘center’ to all areas of the Indian Ocean, to even the African
Coast and beyond.
Numerous, yet conflicting, Western media reports also continue
to be generated about this cataclysmic event with no regard to
science fact but rather relying on speculation alone.
Reports are varying to many extremes of sea floor horizontal
and/or vertical movement, such as one report that states,
“slippage occurred along about 1,200 km of the interface between
the tectonic plates”, and another that states that it was, “…a
600-mile-long (965km) rupture that generated a 35ft vertical
displacement in the sea floor.”
But the differences in how many kilometers of vertical
displacement did or did not occur, or how high or low various
parts of the sea floor rose or fell are not as important as to
how fast these assertions of fact were being spread by the
Western media sources.
They in fact began within hours of the cataclysm occurring, with
no scientific research being conducted and in contradiction to
what the United States National Geophysical Data Center had
reported and Prof Ravinder Kumar of the Centre of Advance
Studies in Geology, Punjab University who has said, “There is no
historic record of a tsunami in the Indian Ocean.”
This information alone does not constitute proof of a meteorite
strike being the cause of this cataclysmic, but neither do the
pronouncements by the Western media stating the cause as being
an earthquake event. The behavior of the waves in the Indian
Ocean though do suggest a meteorite due to their concentric
nature of flowing throughout the oceans basin, where if these
were caused by an earthquake would have been omni or bi directed
only as scientists have previously predicted, and particularly
in a region where no historical reports of a tsunami had ever
been recorded.
Not being connected in the Western Media about this event either
was its precursor which occurred in the Macquarie Island region
of Antarctica and was measured as an 8.2 event on the Richter
scale. (An 8.2 Richter event is equal to 3 billion tons of TNT
and the 9.0 event in the Indian Ocean was equal to 32 billion
tons.) But released almost simultaneously with the Antarctica
8.2 event was a report from the United States space organization
NASA’s Near Earth Object Program in an ‘Asteroid Alert’ which in
part said,
“For comparison, the Barringer Meteor Crater in
northern Arizona is thought to have been created by an iron
meteorite between 30 and 100 meters in diameter. Its impact
would have released energy equivalent to about 3.5 million tons
of TNT.”
More interesting in the light of these recent events are that
these two events have more in common than their historically
rare power in that both the Antarctica event and the Indian
Ocean event are connected by their sameness in both geological
and magnetic anomalous features, and as previously mapped by
scientists.
One such other area on the earth is known as the Cayman Trough
and is located in the Northwest Caribbean Sea.
A number of the world’s top scientists in their fields have
reported on this region in a report that in part says,
“We
review the plate tectonic evolution of the Caribbean area based
on a revised model for the opening of the central North Atlantic
and the South Atlantic, as well based on an updated model of the
motion of the Americas relative to the Atlantic-Indian hotspot
reference frame. We focus on post-83 Ma reconstructions, for
which we have combined a set of new magnetic anomaly data in the
central North Atlantic between the Kane and Atlantis fracture
zones with existing magnetic anomaly data in the central North
and South Atlantic oceans and fracture zone identifications from
a dense gravity grid from satellite altimetry to compute North
America-South America plate motions and their uncertainties.”
As we are all aware, the largest magnetic anomalous area in the
world is located in Russia and is named the Kursk Satellite
Magnetic Anomaly (KMA), and in the memory of our fallen heroes
from the great Russian Submarine Kursk of the same naming.
