Mammoth Extinction Due to Giant
Solar Flares, Not Supernova Comet
active Sun and increased comet bombardment triggered by a Galactic
cosmic ray volley may have led to the extinction of the mammoth
about 13 thousand years ago according to research conducted by
astrophysicist Paul LaViolette of the Starburst Foundation.
LaViolette first presented evidence for his theory
in his 1983 Ph.D. dissertation which he worked on at Portland
State University in Oregon. Astronomical evidence he had gathered
indicated that every 10,000 years or so intense volleys of cosmic
ray electrons are unleashed from outbursts of our Galaxy's core
and make their way to us traveling at close to the speed of light.
Further he reasoned that one such "Galactic superwave"
had bombarded our solar system near the end of the ice age causing
large quantities of cometary dust to enter the solar system along
with an increased influx of meteors and comets. He proposed that
this triggered a sequence of events including the occurrence
of super-sized solar flare outbursts that led to the extinction
of the large mammals 13 thousand years ago.
He postulated that these superwave cosmic rays created
a sheath of radiation around the solar system hot enough to vaporize
the surface of orbiting comets and fill the solar system with
a dense cloud of cosmic dust. He theorized that the process also
would have fragmented some comets and sent large chunks, some
of comet size, careening into the inner solar system. He proposed
that the presence of this dust had affected the Earth's climate
and aggravated the Sun, causing it to create giant solar flares.
During this extended two millennium period, he says, Pleistocene
megafauna were being plagued by elevated UV radiation and catastrophic
floods of glacial meltwater discharged from the surface of the
ice sheets. He proposed that at least one giant-sized solar coronal
mass ejection may have been strong enough to overpower the Earth's
geomagnetic shield and scorch the Earth, thus creating the final
chapter in the decimation of the megafauna whose remains in some
cases are found to have abnormally young radiocarbon dates. He
elaborates on this in his book Earth Under Fire as well as in
various journal papers. LaViolette apparently is on the right
track since data that later came out showed that atmospheric
radiocarbon experienced an anomalous 7 percent increase over
the period spanning the Younger Dryas transition boundary.
In the early 80's, as a key test of his theory, LaViolette
had analyzed samples of polar ice for the presence of iridium
and nickel. He found that on at least six occasions during the
mid and early stages of the last ice age cosmic dust incursion
episodes had occurred. His theory predicted that he should also
find high concentrations of cosmic dust during the interval from
11,000 to 14,000 years ago that spanned the extinction of the
large Pleistocene mammals. But at that time he was unable to
complete this crucial test of his theory because of lack of available
ice samples spanning this interval. At that time, LaViolette's
findings were considered quite novel, particularly his discovery
that certain ice age polar ice samples contained high levels
of tin along with iridium and nickel, for such high tin concentrations
had never before been seen in extraterrestrial material.
Now, however, a group of 26 scientists, led by Lawrence
Berkeley Lab scientist Richard Firestone and geologist Alan West,
has found overwhelming evidence that high levels of extraterrestrial
material are present at the 12,900 year old Younger Dryas mass
extinction boundary, thus confirming LaViolette's 24 year old
prediction. As described in their paper in the October 9th issue
of the Proceedings of the National Academy of Sciences, the Firestone-West
"Younger Dryas boundary (YDB) group" found high
concentrations of iridium, nickel, tektites, fullerenes, nanodiamonds,
and helium-3 at this boundary, a date that also marked the end
of the two-millennium-long megafaunal extinction episode (Firestone,
et al., 2007). In particular, part of the YDB group (Darrah,
et al., 1977) reported that magnetic separates from the YD boundary
contained high levels of tin and copper, thereby corroborating
LaViolette's earlier conclusion that the tin he had found was
of cometary dust origin and evidence of a past superwave passage.
Firestone et al. propose that a comet at least several
kilometers in diameter had impacted the North American ice sheet
or fragmented and exploded in the atmosphere and that its fireball
induced a global firestorm followed by glacial meltwater flooding.
They propose that these events together with the initial shock
wave and release of noxious gases were a chief cause of the megafaunal
extinction. LaViolette's prediction that high concentrations
of cosmic dust should be found in the interval spanning the 13
thousand year old Younger Dryas transition boundary emphasized
more the idea of enhanced cometary dust deposition, although
the notion of a comet impact occurring at this time is also compatible
with his theory which projected an increased influx of comets
and meteors during this time.
However, LaViolette believes that the comet impact
was not a main cause of the extinction. His theory proposed
a more extended die-off episode climaxing with a particularly
large solar flare and associated episodes of global conflagration
and glacial meltwater flooding. This scenario later received
strong support from discoveries that this period was marked by
a 700 year rise in radiocarbon concentration, an indicator of
elevated solar activity, as well as by an extended increase in
atmospheric beryllium-10 production, an indicator that Galactic
cosmic ray intensity had been elevated at that time. LaViolette
points out that a Younger Dryas boundary comet impact does
not account for such effects.
In their book and earlier conference presentations Firestone
and West proposed that this impacting comet originated from
a supernova explosion about 250 light years away that
took place about 41,000 years ago and that the comet
was part of the supernova's high-velocity remnant shell
that was passing through the solar system at that time. LaViolette,
however, takes exception to this supernova theory. In his current
paper "The cause of the megafaunal
extinction: Supernova or Galactic core outburst?"
he presents 22 major problems with the Firestone-West theory,
some of which include:
Their proposed supernova
has insufficient material to form their proposed comet, falling
short by a factor of 100 million even for an impact by even a
modest sized 1 kilometer diameter comet.
A 12,900 year old comet
explosion/impact cannot account for the finding that the death
rate of these extinct mammals began to rise 2000 years before
this comet impact date nor can it account for the increase
in atmospheric C-14 concentration which began rising 500
years prior to this date.
Their proposal that the
comet should have entered the solar system at one percent of
the speed of light, a hundred times faster than most comets,
is extremely problematic. A comet traveling at such a high
speed would impacted with far too much energy. For
example an impact by a 480 km comet, a size Firestone and
West suggest in their book, would have released an energy
equivalent to a trillion megatons of TNT, instantly turning
our atmosphere into a plasma. The Earth would have
no atmosphere today if this were true.
remnant shells (7000 to 28,000 years old) have not been
observed to expand at the enormous speeds they propose (e.g.,
10,000 to 2,500 kilometers per second), nor is there any
evidence of such a high velocity shell being present in
the Sun's vicinity.
Hot supernova gases cannot condense into frozen
cometary bodies in just 28,000 years, nor into hypervelocity
iron grains in just 7,000 years, as Firestone and West have
Their proposal that iron
grains were traveling at 3 percent of the speed of light
and pelted 34,000 year old mammoth tusks is seriously flawed.
If they were traveling at this speed, such hypervelocity
particles would have completely vaporized before reaching
the Earth's surface. Also the quantity of ferrous metals
that a supernova at this distance would have been able to shower
on the Earth falls short by at least 100,000 fold.
Their claim that the
40,000 year old peak in beryllium-10 concentration seen
in the polar ice record was produced by their proposed 41,000
year old supernova explosion is problematic. Be-10
begins its rise several thousand years prior to their proposed
date and spans a total of 6000 to 7000 years. A supernova gamma
ray flash by contrast should have produced a spike lasting just
two years. The same time mismatch is seen in the radiocarbon
record for this period.
do not occur frequently enough to explain the more than
a dozen beryllium-10 peaks seen in the polar ice record, eight
of which precede Firestone-West's proposed supernova date.
On the other hand, such frequently occurring peaks are expected
on the basis of the superwave theory, which predicted their existence
before the Be-10 data was even published.
do not occur frequently enough to explain the numerous cosmic
dust peaks seen in the polar ice record. However, superwaves
do occur frequently enough.
Some of the YDB group collaborators also have
reservations with Firestone and West's supernova theory. One
is anthropologist William Topping who had coauthored a paper
with Firestone in 2001 in the Mammoth Trumpet. Topping
had studied YD boundary PaleoIndian artifacts during the 1990's
and, like LaViolette before him, had concluded that a giant solar
coronal mass ejection must have been a key factor responsible
for the demise of the megafauna as well as for the disappearance
of the Clovis mammoth hunters.
Darrah, T H, et al. "Mineralogical and noble gas evidence
for an ET impact at the Younger Dryas." Paper PP41A-04,
May 2007 AGU Conference, Acapulco, Mexico.[http://www.agu.org/meetings/sm07/sm07-sessions/sm07_PP41A.html]
Firestone, R. and Topping, W. "Terrestrial
evidence of a nuclear catastrophe in Paleoindian times."
Mammoth Trumpet 16(2) March 2001, pp. 9 - 16. [http://abob.libs.uga.edu/bobk/nuclear.pdf]
Firestone, R. West, A., and Warwick-Smith,
S. The Cycle of Cosmic Catastrophes. Rochester, VT, Bear &
Firestone, R. B., et al. "Evidence
for an extraterrestrial impact 12,900 years ago that contributed
to the megafaunal extinctions and Younger Dryas cooling."
Proceedings of the National Academy of Sciences 104, October
9, 2007c, 16016 -16,021. [http://www.pnas.org/cgi/doi/10.1073/pnas0706977104].
LaViolette, P. A. Galactic Explosions,
Cosmic Dust Invasions, and Climatic Change. PhD dissertation,
Portland State Univ., (1983a) Portland, Oregon, pp. 763 (Univ.
Micro. No. 83-24,329); [http://adsabs.harvard.edu/abs/1983PhDT.........9L]Later
published as Galactic Superwaves and Their Impact on the Earth
Environment (includes more recent supporting evidence being added
between 1994 and 2007).
LaViolette, P. A. "The terminal Pleistocene
cosmic event: Evidence for recent incursion of nebular material
into the solar system." (abs.) Eos 64, p. 286; Spring AGU
meeting, Baltimore, May 1983b.
concentrations of cosmic dust in Wisconsin stage polar ice."
(abs.) Meteoritics 18, p. 336; 46th meeting of the Meteoritical
Society, Mainz, September 1983c.
superwaves and their effect on the Earth and Solar System."
(abs.) Presented at the Galaxy and Solar System Conference, Tucson,
of high cosmic dust concentrations in late Pleistocene polar
ice." Meteoritics 20 (1985b): 545-558. [http://adsabs.harvard.edu/abs/1985Metic..20..545L]
ray volleys from the Galactic center and their recent impact
on the Earth environment." Earth, Moon, and Planets 37 (1987a):
. "The cometary
break-up hypothesis re-examined." Monthly Notices Royal
Astronomical Society 224 (1987b): 945-951.
the validity of polar trace metal data: A response." Monthly
Notices of the Royal Astronomical Society 233 (1988): 221-224.
core explosions and the evolution of life." Anthropos 12,
1990, pp. 239 - 255.
of the Ulysses interstellar dust findings." Eos 74(44) (1993):
. Earth Under Fire. Rochester,
VT: Bear and Co., 1997, 2005a.
. "A galactic superwave hazard
alert." Nexus 8(2) February - March 2001, pp. .
. "Solar cycle variations in ice
acidity at the end of the last ice age: Possible marker of a
climatically significant interstellar dust incursion." Planetary
and Space Science 53(4) (2005b): 385 - 393. eprint: [arxiv.org/abs/physics/0502019]
. "Evidence for a global warming
at the termination I boundary and its possible cosmic dust cause."
2005c; eprint: [[http://starburstfound.org/downloads/superwave/TPI.pdf]]
LBNL, "Supernova may have caused
mammoth extinction." Sept. 23, 2005 Lawrence Berkeley National
Laboratory press release, September 23, 2005.[http://www.lbl.gov/Science-Articles/Archive/NSD-mammoth-extinction.html]