Robert Mitchum
Chicago Tribune
Thu, 01 Jan 2009 20:50 UTC
A Comet may have exploded over planet, causing fires, die-offs, researchers say
In an article to be published Friday in the journal Science,
researchers present what one author calls the "smoking bullet" - proof
that an exploding comet triggered the sudden, thousand-year freeze that
killed off mammoths, saber-toothed tigers and other large mammals that
used to live in North America.
Working at multiple sites across the continent, researchers
found nanodiamonds - microscopic particles thought to be found on
comets - in a 13,000-year-old layer of carbon-rich soil.
The authors, led by University of Oregon anthropologist
Douglas Kennett, theorize that the comet exploded above the Earth's
surface, raining fragments upon North America and starting fires across
the continent. That would have ushered in an abrupt global cooling and
caused the "megafauna" extinction.
In the layer with the nanodiamonds, fossils of the
large mammals are abundant. After that layer, they disappear, said
Allen West, an Arizona geophysicist and one of the paper's authors.
"It's extraordinary that tens of millions of animals
disappeared synchronously at exactly the time when the diamonds and
carbon layer are laid down across the continent," West said.
West said the event also would have affected human populations
of the time. Artifacts from the Clovis culture of humans - an early
hunter-gatherer society - also disappear after the 13,000-year layer,
suggesting they, too, were killed off by the comet or its aftereffects.
Many archeologists remain skeptical of the comet theory, said
Daniel Amick, an associate professor of anthropology at Loyola
University Chicago who studies the Clovis culture.
"When most archeologists heard about it they were somewhat
dismissive," Amick said. "We would think, 'How in the world could we
have missed this? How could this spectacular kind of event have
occurred and never even dawned on us?' "
The authors have much to prove before their theory is
accepted, Amick said, like pinpointing the date of the event and ruling
out other potential causes of extinction and climate change.
In response to one common criticism of the comet theory - that
no craters have been found from an impact - West said the comet may not
have actually reached Earth, but exploded into fragments somewhere
above the surface.
Researchers found the highest concentration of nanodiamonds at
a site in eastern Michigan, which suggests the comet may have exploded
somewhere over the Great Lakes, West said.
"We think that Chicago might well have been very near ground
zero," West said. "If you'd been in Chicago back in that time, it
would've been one very bad day."
The possibility of a comet causing catastrophic climate change
and extinction relatively recently in Earth's long history suggests
scientists shouldn't dismiss the possibility of it happening again,
West said.
"Unlike mammoths, who might happen to look up and see the
thing coming at them from the sky but can't do anything about it, we're
in a position of civilization where we can possibly deflect these
things," West said.
Greg Bolt
The Register-Guard
Thu, 01 Jan 2009 04:06 UTC
A controversial theory linking the extinction of mammoths to an ancient
comet strike is gaining some shine from the discovery of a special kind
of diamond found glittering in a super-powerful microscope.
University of Oregon archaeologist Doug Kennett, a leading
proponent of the theory, said the diamonds are extremely small - a few
billionths of a meter across. Because of their size they are known as
nanodiamonds and are believed to be formed in the intense heat and
pressure of a meteor or comet impact.
The presence of the diamonds adds weight to the idea
that the Earth was hit by a comet about 12,900 years ago, plunging the
planet into a new ice age just as it was coming out of the last one. As
a result, nearly all large animals in North America, including mammoths
and mastodons, became extinct and the continent's earliest human
colonies were decimated.
Was it a meteor falling from space?
Officials think that might be what residents saw shooting through the Alaska sky near Tok on Monday afternoon.
A tremendous explosion, like a sonic boom, drew some people outside,
where they watched irregular contrails scribe a path in a clear sky.
At her home four miles west of Tok, Kathy Olding was
loading a large sled with firewood to haul to her house when she was
startled by an explosion. Peering out from the tarp-covered wood pile,
she saw even her imperturbable Chesapeake Bay retriever, Journey, was
on edge, ears cocked.
"I could kind of hear it still rumbling, like thunder," she recalled. "I thought, what in the world?"
Turning her eyes to the sky, Olding saw the oddest contrail.
"It was just like somebody took a pen and made a white cloud
that went up and down and up and down and squiggley," she said,
describing the pattern.
Others called 911.
Alaska State Troopers dispatcher Diane Kendall fielded several calls starting about 3:30 p.m. Most reported a loud explosion.
One caller, an adult, told Kendall an 11-year-old witnessed the entire spectacle outside.
"He said it was like a big fireball that exploded, with smoke
everywhere," Kendall relayed. "The kid said, 'I think it was a meteor,'
and I went, right. The Martians have landed. But then I got three other
calls, boom, boom, boom. I was pretty shocked."
People reported hearing and feeling an explosion in the air,
but no one called in about debris falling from the sky, said Sgt.
Freddie Wells, the state trooper on duty at the time.
Responding to the reports, he went out and caught a glimpse as well.
"It seemed to appear like smoke, or a dust cloud," he said.
Fearing some sort of airplane disaster, Wells had his dispatcher call the Federal Aviation Administration in Fairbanks.
"The FAA did confirm that it was a meteor," Wells said.
Kendall called the FAA in Fairbanks. Kendall confirmed she was
told that the flying object was a meteor, and that others reported
seeing a similar phenomenon from the Parks Highway.
But the FAA has no official information on a meteor, said Claudia Hoversten, acting administrator for the Alaskan region.
However, inquiries and calls concerning unidentified flying
objects are not all that unusual, she said. The FAA refers many callers
to the National UFO Reporting Center near Seattle, she added.
John Chappelow is a post-doctorate researcher at the Arctic
Super-Computing Center at University of Alaska Fairbanks. He said the
object could have been a meteor, but the sonic boom-type sound is
atypical.
"That's a very rare event," he noted. "It's hard to say. It could have been a sonic boom. I wouldn't rule out a meteor."
He also noted that bright meteors and fireballs are not too
unusual to see. Sounds, however, would be delayed reaching people's
ears, maybe by as long as 30 seconds. Objects from space have to be
quite large in order to cause sounds such as people around Tok
described, a rare event but not unknown. A meteor generating a sonic
boom-type noise would have been at least the size of a basketball, he
suggested.
Others in Tok also heard the blast. Several of Olding's friends, including one person in Chicken, compared stories.
Some residents would like an official word on what they
witnessed. Rumors abounded for a few days, ranging from the results of
a secret military test gone haywire to a satellite explosion or even
visitors from space.
"This is highly unusual for many, many Tokites to have heard
this explosion," Olding wrote in an e-mail. "Does ANYONE know what it
was? We are all dying to know."
News that the mysterious incident was likely a meteor was somewhat reassuring, laying to rest Martian theories.
"We're looking for UFOs around here," Sgt. Wells joked.
Chappelow said nearly all meteors that leave visible trails in
the atmosphere are no bigger than a BB, and most are as tiny as a grain
of sand. The brightness comes from the speed meteors travel into the
Earth's atmosphere.
A fireball reportedly lit up the early morning sky south of Calgary early Monday.
The Canadian Fireball Reporting Centre received about a dozen reports
of a meteorite falling to earth at about 5:45 a.m. but the hazy
conditions have made it difficult to verify.
"I don't know how anyone saw it. There were a lot of clouds up
there," said the University of Calgary's meteorite expert, Alan
Hildebrand. "But it's possible there was a hole in the clouds that
allowed them to see it. It's happened before."
It could've been a meteorite or possibly falling debris from a meteor shower, said Hildebrand.
"I haven't spoken to any witnesses myself yet," he said. "I'm not even sure exactly where it was."
On Nov. 20, a bright flash lit up the sky, visible from Alberta to Manitoba.
So far, researchers have found more than 100 pieces of that meteorite,
strewn over a 21-square-kilometre area of Saskatchewan just east of the
Alberta border. Scientists were able to narrow down an impact zone
because the trajectory of the fireball was caught on multiple security
cameras. Hildebrand has estimated that over 10,000 pieces may have
fallen to the ground that night.
Hildebrand said that Canadian Fireball Reporting Centre receives about 70 reports of sightings each year.
Science Daily
Wed, 07 Jan 2009 16:44 UTC
Scientists have discovered only the second example of a meteorite
impact that occurred at the same time as massive volcanic activity, in
research published in the Journal of the Geological Society
the week of Jan 12. The first time such a coincidence was observed, at
the Cretaceous-Tertiary boundary, was the catastrophic event thought to
be responsible for the extinction of the dinosaurs, 65 million years
ago.
This new event, uncovered after the 17 km diameter Logoisk
impact structure in Belarus was precisely dated, is thought to have
taken place around 30 million years ago. The crater was dated using
argon isotopes, and found to have occurred at a similar time to a
period of massive volcanism known as the Afro-Arabian flood volcanism,
which started in NW Yemen at around 30.9 Mya, and SW Yemen at around
29.0 Mya.
The impact also coincides broadly with a period of sudden global
cooling and sea level fluctuation. The researchers, led by Sarah
Sherlock at the Open University, argue that massive volcanic eruptions
and meteorite impacts are likely to have coincided much more frequently
than has previously been thought, but because the preservation of
impact craters on Earth is poor much of the evidence for these
coincidences is lost.
The relationships between meteorite impact craters,
volcanism and changes in climate is a subject of much debate among
scientists. Prior to the study, only one example of an impact
coinciding with volcanism had been found: the Chicxulub and Boltysh
impacts and the Deccan Traps flood volcanism, all of which occurred at
the Cretaceous-Tertiary boundary. In 2002, the discovery of their
coincidence with a global mass extinction led to debate over the
causative links between meteorite impacts, volcanism and mass
extinction events, and fuelled the search for more impacts at
stratigraphic boundaries.
Unlike the Cretaceous-Tertiary event, the combination of the
Logoisk impact and the Afro-Arabain flood volcanism does not seem to
have caused an extinction event. The researchers suggest that the
reason for this may be that the magnitude of the event was not
sufficiently large in comparison. Whilst the Chicxulub crater
associated with the extinction of the dinosaurs measures 170km in
diameter and the Deccan Traps released around (2-4) x106 km3 of lava,
in comparison the Logoisk impact structure measures 17km across and the
Afro-Arabian flood volcanism is around 1.2 x106 km3 in volume.
As a result, the effects of each event were likely to have
been very different. At the Cretaceous-Tertiary boundary, it is thought
that one of the deadly effects was the release of sulphur dioxide,
either as acid rain or in the stratosphere, where it would have
prevented heat from reaching the earth and caused massive global
cooling. Around 8000 billion tons of SO2 are thought to have been
released by the volcanism and meteorite impact. In comparison, the
Logoisk impact and the Afro-Arabian volcanism are thought to have
contributed only 30 billion tons of SO2.
Meteorite impact craters are extremely difficult to date, but
an understanding of their age and frequency is crucial to attempts to
control the number of future impacts, as well as understanding the
links between impacts and other catastrophic events such as large
volcanic eruptions and mass extinctions. Around 90% of the Earth's
record of meteorite impacts is lost, and the researchers argue that
coincidences between impacts and flood volcanism are far from rare.
They suggest that, for every incidence of flood volcanism, at least one
crater the size of Logoisk is likely to form, although few such
coincidences are likely to be on a scale grand enough to bring about an
extinction event comparable with that which destroyed the dinosaurs.
Journal reference:
Sarah C. Sherlock, Simon P. Kelley, Liudmila Glazovskaya and
Ingrid Ukstins Peate. 'The significance of the contemporaneous Logoisk
impact structure (Belarus) and Afro-Arabian flood volcanism. Journal of the Geological Society, Vol. 166, 2009, pp. 1-4
Multiple comet impacts around 1500 years ago triggered a "dry fog" that plunged half the world into famine.
Historical records tell us that from the beginning of March 536 AD, a
fog of dust blanketed the atmosphere for 18 months. During this time,
"the sun gave no more light than the moon", global temperatures
plummeted and crops failed, says Dallas Abbott of Columbia University's
Lamont-Doherty Earth Observatory in New York. The cause has long been
unknown, but theories have included a vast volcanic eruption or an
impact from space.
Now Abbott and her team have found the first direct
evidence that multiple impacts caused the haze. They found tiny balls
of condensed rock vapour or "spherules" in debris inside Greenland ice
cores dating back to early 536 AD. Though the spherules' chemistry
suggests they did not belong to an impactor, they do point to
terrestrial debris ejected into the atmosphere by an impact event,
Abbott says. "This is the first concrete geological evidence for an
impact at 536 AD," she says.
The fallout material was also laid down over several years, and some layers were particularly densely deposited. This suggests more than one impactor was involved - probably a comet, because they tend to fragment on their way to Earth.
Abbott and her team have identified two possible underwater
craters whose age ranges fit the global dimming event. The first
appears to have formed when an object roughly 640 metres wide slammed
into the Gulf of Carpentaria in Australia, and the other when a smaller
object crashed into the North Sea near Norway.
Marine microfossils found with the impact spherules are also
consistent with an ocean impact. "There's clearly stuff that has been
transported a long distance," says Abbott, who presented the team's
findings at the meeting of the American Geophysical Union in San
Francisco last month.
Big meteor last night! (Jan 7) Anyone else see it?
Half Moon Bay, California - We were heading south on 1 at Montara Beach, Jan 7, about 8:45 PM.
The meteor appeared to the southwest. It was quite low, just above the
treeline, but winked out before it was obscured by the trees.
It lasted for about a 3 second glow once we saw it
appear below the top of the windshield, moving slowly, near vertically
from our viewpoint. It was by far the brightest meteor either of us
have ever seen, easily as bright as the airliner landing lights coming
into San Francisco International Airport as seen from Skyline. The glow
was more diffuse than a jet light though.
It was really spectacular. Anyone else see it?
Wendy Patterson
Miramichi Leader
Fri, 09 Jan 2009 18:42 UTC
Driving between Bathurst and Miramichi on New Year's Eve, one motorist
and his passenger saw a different kind of fireworks in the sky.
Mike Gallant was on his way from Bathurst to Moncton when, at
exactly 4:45 p.m., he saw a luminous teal-blue streak that lit up the
darkening sky. "It looked like a meteor to me," he said. "It was clear
as day to myself and my passenger."
He described the streak as being darker on the bottom and
lighter in colour towards the top, although the entire object was
extremely bright. "It completely brightened the sky," he said.
He explained that the object showed up suddenly,
appearing to come from the clouds or above them, and disappeared
without seeming to land. However, he said that it was impossible to
tell how far away it might have been.
"It may have been miles," he said.
Meteorologist Claude Côté with Environment Canada in
Fredericton said that this was the first report he had heard of a
meteor sighting on New Year's Eve. But he added that Jan. 3 was the
peak for the Quadrantid meteors, which can be seen streaking through
the sky about this time each year, and that there was a report of a
possible fireball sighting in the sky over Sainte-Anne-de-Kent on Dec.
28, a few days before Gallant's sighting.
A fireball, according to online encyclopedia Wikipedia, is an
unusually bright meteor, which The International Astronomical Union
defines as "a meteor brighter than any of the planets." Meteors are
small particles of debris in space that enter the Earth's atmosphere
and are seen as "shooting stars." They can range in size from grains of
sand to boulders.
Gallant said he was surprised that no one else had reported
seeing the flash of light on New Year's Eve, as there was a lot of
traffic on the highway. He actually waited about a week to report the
sighting himself, he said, for fear that no one would believe him.
He added that he spent the rest of the holidays researching
the phenomenon. "My interest has been sparked," he said. "I'm quite
interested in meteors." He continued that he has heard about quite a
few meteor sightings in Canada recently, and footage he found on the
Internet of a fireball in Lloydminster, Alberta in November looked
familiar.
"What I saw looked a lot like that," he said.
Gallant added he wishes someone had recorded the meteor he saw,
but they would pretty much have to have been already taping the sky
when it happened. "It was so quick," he explained.
Overall, he said, it was a very memorable experience.
"It was quite scary, actually. I was pretty well floored by it." But nevertheless, he said, "I felt kind of lucky to see it."
Comet Lulin (C/2007 N3), discovered in 2007 by a Strait-bridging
team of astronomers from Taiwan and China, is swinging around the sun
and approaching Earth. Astronomer Karzaman Ahmad sends this picture
taken Jan. 7th from the Langkawi National Observatory in Malaysia:
© Karzaman Ahmad
"I used the observatory's 20-inch telescope for an exposure of 24
minutes," he says. "The image shows the comet's bright tail and an
anti-tail."
Right now, Comet Lulin is gliding through the constellation Libra in the southeastern sky before dawn: sky map.
It glows like an 8th magnitude star, so a mid-sized backyard telescope
is required to see it. Visibility will improve in February as the
Earth-comet distance shrinks. At closest approach (0.41 AU) on February
24th, the comet should brighten to about 5th magnitude--dimly visible
to the unaided eye and an easy target for binoculars: ephemeris.
Surprises are possible. The hyperbolic orbit of Comet Lulin
suggests this could be the comet's first visit to the inner solar
system. How it will react to increasing sunlight is anyone's guess.
Stay tuned for updates in the weeks ahead.
BONUS: Chinese astronomer Quanzhi Ye co-discovered the comet and he is continuing to monitor it. "This photo
taken on Jan. 5th comes from the same telescope at the Lulin
Observatory in Taiwan used to find the comet in the first place," says
Ye. "I was only 19 years old at the time of the discovery. I hope that
my experience might inspire other young people to pursue the same
starry dreams as myself."
Shreveport, Louisiana gets a fair number of visitors. And with recent
movie activity, some might even be called stars; however, a guest from
the heavens might literally have dropped in.
About 6 p.m. Thursday, people near Cross Lake saw a bright
flash and heard an explosion that rattled windows and brought them out
of their houses and onto their yards to look over the water.
Speculation over what it could have been included a bomb and a
methamphetamine laboratory hidden in the woods.
It took a while for people to arrive at the logical conclusion: It probably was a meteor.
"Meteors happen all the time,"
says Kevin Kilkenny, fireball coordinator for the North American Meteor
Network. It's part of international consortium of agencies that track
and monitor meteors, which are asteroids and other celestial objects
that enter the atmosphere, and meteorites, which are those that
actually strike the Earth. "The problem is that very few people look at the sky anymore and are not familiar with the sights that can be seen all the time."
Caroline Thomas lives on South Lakeshore Drive, not far from Barron's
Landing, and said it was just getting dark "when I heard this horrible
... the loudest explosion I've ever heard and saw this big flash."
She called Shreveport police's Cross Lake Patrol and joined the gaggle looking onto the lake.
Bob Terrell at Barron's Landing and his boss, Tanya Luker, heard the explosion.
"It was very quick," Terrell said. "But there was an extremely
loud explosion and fire that lasted an instant, and then it was gone.
It was that quick."
He said he served in the Air Force and heard many sonic booms
in his life. "But this was louder than any sonic boom, and it was very
scary, to say the least."
Luker agreed. "It rattled the glass. It was an intense explosion."
While the lake patrol got calls about the object, state police,
units at Barksdale Air Force Base and the National Weather Service did
not.
Lake patrol officers checked for any debris, damage or cause
but came up empty-handed, Shreveport police spokesman Randy Patrick
said.
"It rattled windows. But they have no idea what caused it."
Kilkenny said there are major and lesser meteor showers going on nearly every night of the year.
"The major ones, like the famous Perseids and Geminids, have
the possibility to produce from dozens to hundreds per hour. Minor
showers like the Taurids may only produce a few meteors per hour," he
said.
"But each year, tons and tons of space 'rock' falls to Earth. Most are micro size."
"So far, yours is the first notice we're receiving about this
'exploding meteor,'" Kilkenny said. "If we hear more about this
fireball from Louisiana or neighboring states, we will certainly let
you know."
Thomas, who hasn't seen or heard anything like this in the
more than 36 years she's lived on Cross Lake, said it was enough
excitement for one afternoon.
Media Newswire
Mon, 12 Jan 2009 16:11 UTC
The
researchers hypothesize that that the asteroid had a diameter somewhat
larger than 100 kilometers, which would be sufficient to hold enough
heat for the asteroid's rocks to partially, but not completely, melt.
The asteroid would remain undifferentiated, but the melted portions
could erupt on the asteroid's surface to form the andesitic crust.
Asteroids are hunks of rock that orbit in the outer reaches of space,
and scientists have generally assumed that their small size limited the
types of rock that could form in their crusts. But two newly discovered
meteorites may rewrite the book on how some asteroids form and evolve.
Researchers from the Carnegie Institution, the University of Maryland,
and the University of Tennessee report in the January 8th edition of Nature
that these meteorites are ancient asteroid fragments consisting of
feldspar-rich rock called andesite. Similar rocks were previously known
only from Earth, making these samples the first of their kind from
elsewhere in the Solar System.
The two meteorites were discovered during the Antarctic Search
for Meteorites (ANSMET) 2006/2007 field season in a region of the
Antarctic ice known as the Graves Nunatak icefield. The light-colored
meteorites, designated GRA 06128 and GRA 06129, were immediately
recognized as being different from previously known meteorites.
"What is most unusual about these rocks is that they
have compositions similar to Earth's andesite continental crust - what
makes up the ground beneath our feet," says University of Maryland's
James Day, lead author of the study. "No meteorites like this have ever
been seen before."
Andesite is an igneous rock common on Earth in areas where
colliding tectonic plates generate volcanoes, such as those of the
Andes mountain range. The meteorites contain minerals thought to
require large-scale processes such as plate tectonics to concentrate
the right chemical ingredients. In view of this, some researchers had
suggested that the meteorites were fragments of a planet or the Moon,
not an asteroid. But analysis of the meteorites' oxygen isotopes at the
Carnegie Institution's Geophysical Laboratory by Douglas Rumble ruled
out that possibility.
"A number of solar system objects including parent bodies of
meteorites, planets, moons, and asteroids have their own oxygen isotope
signatures," says Rumble. "Just by analyzing 16O-17O-18O ratios we can
tell if a meteorite came from Mars, from the Moon, or from a particular
asteroid. One extensively studied parent is the asteroid 4 Vesta. In
the majority of cases the actual location of the parent body is
unknown, but a particular group of meteorites may be assigned to the
same parent body based on the isotope ratios even if the specific
location of the body isn't known. When the ratios in meteorites are
plotted against one another the result is mutually parallel lines
offset from one another. The GRA 06128 and GRA 06129 meteorites, and
some similar ones called brachinites, plot below Earth-Moon rocks and
are nearly coincident with meteorites from 4 Vesta."
The meteorites' age, more than 4.5 billion years, suggests
that they formed very soon after the birth of the solar system. This
makes it unlikely that they came from the crust of a differentiated
planet. The chemical signature of some rare precious metals, notably
osmium, in the meteorites also points to their origin on an asteroid
that was not fully differentiated.
The researchers hypothesize that that the asteroid had a
diameter somewhat larger than 100 kilometers, which would be sufficient
to hold enough heat for the asteroid's rocks to partially, but not
completely, melt. The asteroid would remain undifferentiated, but the
melted portions could erupt on the asteroid's surface to form the
andesitic crust.
"Our work illustrates that the formation of planet-like
andesite crust has occurred by processes other than plate tectonics on
solar system bodies," says Day. "Ultimately this may shed light on how
evolved crust forms on planets, including Earth, during the earliest
stages of their birth."
This study was supported by the NASA Cosmochemistry Program.
© Case Western Reserve University
The
new meteorite specimen in the Antarctic Meteorite Processing Laboratory
at NASA's Johnson Space Center. The meteorite was broken open for
initial characterization, revealing a pinkish-tan interior and a
granular texture unusual in meteorites. The cube in the images is 1 cm
on a side and is used to establish a consistent frame of reference for
the geometry of the specimen; labeling the top, bottom, sides, etc.
The
new meteorite specimen in the Antarctic Meteorite Processing Laboratory
at NASA's Johnson Space Center. The meteorite was broken open for
initial characterization, revealing a pinkish-tan interior and a
granular texture unusual in meteorites. The cube in the images is 1 cm
on a side and is used to establish a consistent frame of reference for
the geometry of the specimen; labeling the top, bottom, sides, etc.
Although last year's inclement weather resulted in fewer Antarctic
meteorite recoveries than usual, scientists have recently discovered
that one of the specimens is a rare breed -- a type of lunar meteorite
seen only once before.
The new specimen was found by a field party from the U.S.
Antarctic Search for Meteorites program (ANSMET) headquartered at Case
Western Reserve University. The meteorite was discovered on Dec. 11,
2005, on an icefield in the Miller Range of the Transantarctic
Mountains, roughly 750 km from the South Pole.
This 142.2 g black rock, slightly larger than a golfball and officially
designated MIL 05035, was one of 238 meteorites collected by ANSMET
during the 2005-2006 austral summer. Heavy snows limited search efforts
during much of the remainder of the six-week field season, making this
meteorite, discovered just 600 m from camp, a particularly welcome
find.
Scientists involved in classification of Antarctic
finds at NASA's Johnson Space Center and the Smithsonian Institution's
National Museum of Natural History said the mineralogy and texture of
the meteorite are unusual. The new specimen is a very coarse-grained
gabbro, similar in bulk composition to the basaltic lavas that fill the
lunar maria, but its very large crystals suggest slow cooling deep
within the Moon's crust. In addition, the plagioclase feldspar has been
completely converted to glass, or maskelynite, by extreme shock
(presumably impact events). The new specimen most closely resembles
another Antarctic meteorite, Asuka 881757, one of the oldest known
lunar basalt samples.
Like the other lunar meteorites, MIL 05035 is a piece of the
Moon that can be studied in detail in the laboratory, providing new
specimens from a part of the lunar surface not sampled by the US Apollo
program. Many researchers believe that Apollo visited some of the most
unusual and geochemically anomalous regions of the Moon, and lunar
meteorites, knocked off the surface of the Moon by random impacts, give
us samples that are more representative of the Moon as a whole. The
highly-shocked nature of MIL 05035 suggests an old age and may provide
new constraints on the early intense bombardment of the Earth-Moon
system, improving our understanding of the history of the Earth's
nearest neighbor and aiding NASA's efforts toward a return to the Moon.
Following the existing protocols of the U.S. Antarctic
meteorite program, scientists from around the world will be invited to
request samples of the new specimen for their own detailed research.
Details concerning initial characterization of the specimen and sample
availability are available through the Antarctic Meteorite Newsletter, available on the Web and mailed to researchers worldwide.
Discovery of this meteorite occurred during the fourth full field
season of a cooperative effort by the National Science Foundation (NSF)
and the National Aeronautics and Space Administration (NASA) to enhance
recovery of rare meteorite types in Antarctica, in the hopes new
martian samples would be found.
The US Antarctic Meteorite program is a cooperative effort
jointly supported by NSF, NASA and the Smithsonian Institution.
Antarctic field work is supported by grants from NSF and NASA to Case
Western Reserve University; initial examination and curation of
recovered Antarctic meteorites is supported by NASA at the
Astromaterials Curation facilities at the Johnson Space Center in
Houston, Texas; and initial characterization and long term curation of
Antarctic meteorite samples is supported by NASA and the Smithsonian
Institution's National Museum of Natural History in Washington, D.C.
Peter Vinthagen Simpson
The Local
Sun, 18 Jan 2009 12:19 UTC
A mystical light phenomenon was observed over southern and western Sweden on Saturday evening. Experts believe that a bolid - a burning meteorite - could provide the explanation.
SOS Alarm and the Gothenburg air-rescue service were bombarded with
telephone calls from mystified observers across southern and western
Sweden shortly after 8pm on Saturday evening.
Witnesses reported seeing a huge flash of light stream across the night sky.
"There are a great many people who have seen it. We have
received phone calls from Trelleborg to Lidköping," said Annika
Vestergård at the air-rescue service to news agency TT.
The light shone for only a couple of seconds but was
enough to excite observes and prompt a raft of theories explaining the
phenomenon.
Annika Vestergård said that one working theory is that the
light was caused by a bolid, a meteorite that burns up in the
atmosphere.
This theory is supported by Clas Svahn, chairman of the organisation UFO Sweden.
"This happens around ten times per year in Scandinavia and is therefore quite unusual," he said to Sydvenska Dagbladet.
A further theory is that the flash of light was caused by a fragment of a satellite.
According to Swedish meteorological agency SMHI, there were no weather phenomena that could explain the occurrence.
You can view original article in Danish, here. Translation in English by a SOTT Reader.
A blinding blue green flash on the night's sky followed by an enormous
bang. Many people experienced such a phenomenon across much of Seeland,
Lolland-Falster, Fyen, the eastern Jutland and Bornholm on Saturday
night, around 8.15pm (local time).
Also parts of Southern and Western Sweden could see it, the site sydsvenskan.se reports.
Søren Østervig, a police chief, reports that at the police in
southern Seeland and Lolland Falster police stations, the phone has
been ringing continuously from worried citizens wanting to know what it
was they had just experienced.
A strange light flash
A reader of dr.dk/nyheder, Kenneth Jensen from Horsens (East
Jutland) tells how the sky suddenly lit up with a strange light flash:
"The light was at the beginning constant, after which it
flashed violently like with lightning and then after a few seconds
disappeared silently. I felt it was a most unusual event we experienced
tonight."
A sound like a thunder bolt
Another reader, Leif Wriedt Jørgensen from Gedser, relates that
a large area to the south was lit up for several seconds - perhaps
around 10-15 seconds. After that he witnessed a very sharp light, that
came crashing towards the ground.
"The sound that followed was like a thunder bolt and up
towards five minutes between the light and the sound, which with the
speed of sound would equate to about 100km, between the light and us",
reports Leif Wriedt Jørgensen.
"We are probably talking about a meteor", is
the explanation from Operative Kommando og Sydsjællands og Lolland-
Falsters Politi. The duty officer from the Danish weather bureau agrees
with this assessment and rejects weather phenomena such as lightning as
being the cause of the intense light flash.
Comment: Readers
from Germany and the Netherlands at this link have also reported seeing
the meteorite, which suggests that this was a fairly large "space
rock". Keep watching the skies, 2009 may well turn out to be a
"smashing" year...
San Diego, California - Mulder and Scully of "The X-Files" might need
to be summoned to help authorities solve the mystery of an unidentified
falling object reported Saturday afternoon.
At 2:40 p.m., a caller reported seeing a piece of silver metal
fall from the sky over Interstate 8 by the Pine Valley bridge,
according to a California Highway Patrol dispatcher.
A second caller reported seeing something on fire fall from the sky, said Lt. Anthony Ray of the San Diego Sheriff's Department.
Cal Fire sent an air tanker to check out the reports and a San Diego
Sheriff's Department helicopter crew also looked for the unidentified
falling object, Ray said.
Officers checked with Lindbergh Field and said no planes had been reported missing, according to Ray.
The search continued for more than an hour after the first
call, but deputies on the ground and in the air had not found anything,
Ray said.
A spectacular meteor spotted over Scandinavia on Saturday is likely to have landed in the Baltic Sea, south of Denmark
The meteor that streaked across the sky on Saturday night is likely to
have crashed into the waters off the coast of Denmark, according to a
leading astronomer.
Michael Linden-Vørnle, of the Tycho Brahe Planetarium in
Copenhagen, said all evidence points to a landing site somewhere in the
Baltic Sea south of the islands of Lolland and Falster.
The spectacular phenomenon lit up the skies of southern Sweden
and eastern Denmark at 8:15pm on Saturday night for approximately eight
seconds and prompted dozens of calls to police and emergency services
from worried residents.
Apart from eye-witness accounts, the event was
captured on a surveillance camera in Scania, southern Sweden, which
showed a giant, almost blue, fireball hurtling across the sky.
By Sunday afternoon, more than 400 people had registered their
observations of the meteor on the official Danish meteor website
www.ildkugle.dk.
Henning Haack, curator of the Geological Museum's meteorite collection, told Berlingske Tidende newspaper that the event was very unusual.
'What was most unusual was the boom, together with the fact that it was so powerful.
I've never personally experienced something like that in Denmark in the
10 years that I have been working with meteors,' said Haack, explaining
that the sound likely came from the meteor breaking the sound barrier
in the lower atmosphere.
All experts said it was unlikely that any meteorite remains
will be found on land as much of it breaks down in the atmosphere. The
last time traces of a meteorite were found in Denmark was in 1951 from
a crash site near Århus.
Associated Press
Mon, 19 Jan 2009 05:50 UTC
Nature turned against one of America's early civilizations 3,600 years
ago, when researchers say earthquakes and floods, followed by blowing
sand, drove away residents of an area that is now in Peru. "This
maritime farming community had been successful for over 2,000 years,
they had no incentive to change, and then all of a sudden, boom, they
just got the props knocked out from under them," anthropologist Mike
Moseley of the University of Florida said in a statement.
Moseley and colleagues were studying civilization of the Supe
Valley along the Peruvian coast, which was established up to 5,800
years ago.
The people thrived on land adjacent to productive bays and estuaries, the researchers report in Tuesday's edition of Proceedings of the National Academy of Sciences.
The Supe fished with nets, irrigated fruit orchards and grew cotton and
a variety of vegetables, according to evidence found by research
co-author Ruth Shady, a Peruvian archaeologist. They also built stone
pyramids thousands of years before the better known Mayans.
But the Supe disappeared about 3,600 years ago and, after studying the region, the researchers think they know what happened.
They found that a massive earthquake, or series of quakes,
struck the seismically active region, collapsing walls and floors and
launching landslides from barren mountain ranges surrounding the
valley.
In addition, layers of silt indicate massive flooding followed.
Then came El Nino, a periodic change in the winds and currents
in the Pacific Ocean, which brought heavy rains that damaged irrigation
systems and washed debris into the streams and down to the ocean, where
the sand and silt settled into a large ridge, sealing off the
previously rich coastal bays.
In the end, land where the Supe had lived for centuries became
uninhabitable and their society collapsed, the researchers concluded.
The study was funded by the University of Florida and the Heyerdahl Exploration Fund, University of Maine.
___
On the Net:
PNAS
Comment: Earthquakes, floods and winds - yet no mention of the most obvious explanation for all these phenomena: a cometary impact.
See Laura Knight-Jadczyk's Meteorites, Asteroids, and Comets: Damages, Disasters, Injuries, Deaths, and Very Close Calls.
© La Depeche du Midi
An image of the fireball seen over the Toulouse area skies Saturday 17th Jan 2009
An image of the fireball seen over the Toulouse area skies Saturday 17th Jan 2009
The object was seen in Villemur, Montauban and the Tarn department.
The remnant of a spacecraft? A meteorite fragment? Little green men?
Questions remain after a mysterious apparition literally pierced the
sky in the area North of Toulouse, last Saturday in the late afternoon.
Several persons witnessed what most of them would later describe as a
"big red light falling from the sky".
The object was not only seen in Montauban, but also
around the Tarn border and in Villemur-sur-Tarn, where Martine, a
resident who was coming home from shopping, reported:
"Suddenly, I saw a kind of red square shining like fire. The object
formed an arc in the sky. It was really, really big. I'm a a rational
person and I don't believe in aliens. But I'd like to know what it
was..."
So would many witnesses. In Toulouse's Jolimont observatory, Laurent
Koechlin saw the strange UFO too. He confirms, while remaining
cautious. "We received several calls on Monday. It was indeed a meteor,
which means the object was real and was falling from the sky. It's the
second one I've seen in my life. My opinion would be that it's a
natural element, but we'll have to cross-check the information in order
to know more. I think it was big enough not to be entirely pulverized.
In my opinion, he fell somewhere and should be looked for in the South,
maybe in the Pyrénées."
To be continued...
I scanned your newsletter eagerly this morning looking for any other
report of the comet/asteroid/meteor that was witnessed by my friend
Sunday evening at sunset (I had my back turned). We were at Chase Palm
Park packing up after a day of the arts and crafts show when my friend
said she saw what she thought was a bottle rocket or home-made firework
in the eastern sky.
I didn't think much of it until my mother, who had
spent the day with us, called and reported that on her drive home she
saw something like a blue fireball with a tail shoot across the eastern
sky, moving from 11 o'clock to 4 o'clock. She was on the 101 in La
Conchita at the time. Haven't seen any local or national news on the
"event". Anyone know or hear anything about this?
HBCC UFO Research
Tue, 20 Jan 2009 21:06 UTC
Date: January 20, 2009
Time: Approx: 7:15 p.m.
Location of Sighting: Highway 17 north just east of Sault Saint Marie.
Number of witnesses: 2
Number of objects: 1
Shape of objects: Round.
Full Description of event/sighting: We
were driving home and we saw a bright green fireball the size of a
beach ball in the sky going from west to east at a high rate of speed.
It had a short tail and passed us in approx: 4 to 5
seconds. We would like to know what it was we saw, as nothing like this
has been seen by us before. I am 53 years old and my wife is in her
late 40. Please if any one can let us know what we saw we would like to
know.
The Grand Island Independent
Wed, 21 Jan 2009 02:17 UTC
Tracy Overstreet
The loud booms heard in Grand Island Tuesday night and this morning are
believed to be starling control measures or the acts of curious youth.
Milt Moravek, program manager of the Central Platte Natural Resources
District, said the NRD began shooting off propane cannons last Friday
night for starling control.
"It just scares them away from our area," Moravek said.
The NRD has used the sound abatement method in the past to
prevent the flock from roosting at the NRD headquarters office at 215
Kaufman Ave. It informed the city last week that the cannons would be
shot off around dusk for about seven to 14 days.
But Grand Island/Hall County Emergency Management
Director Jon Rosenlund said the 911 center received calls about loud
booms from "one end of town to the other," and the calls came after
dusk.
They were reported between 9:30 and 10 p.m. Tuesday and again around 7 a.m. today.
Rosenlund said reports were especially prevalent "up and down Stolley Park Road."
"There were no reports of fire, no reports of damage, no reports of power outages or any infrastructure damage," Rosenlund said.
Grand Island Utilities Director Gary Mader said he heard the
boom Tuesday night and called in to the city's power control center.
"It's not us," Mader said. "It didn't seem to be affecting the electric system."
He said the boom almost sounded like a "sonic boom" that is sometimes heard from traveling aircraft.
Calls to the Central Nebraska Regional Airport this morning were not immediately returned.
Other infrastructure also appeared unaffected.
"It's not us," said Claudia Rapkoch, spokeswoman for natural gas provider NorthWestern Energy.
Rosenlund said his supposition is that people are hearing the
NRD starling control, that local residents are implementing their own
starling control measures or that area youth may be experimenting with
something like a "dry ice bomb."
Rosenlund, who didn't advocate this being done, said that,
when dry ice is dropped into a 2-liter bottle of water, a loud
explosion can be the result. The technique has been featured on the
cable television show "Mythbusters."
The city of Grand Island has contracted with the U.S.
Department of Agriculture for starling control in the past, but no such
work is currently under way.
"The city has not received any calls from citizens regarding
problems with starlings," said Paul Briseno, assistant to the city
administrator.
USDA officials have been tracking the birds, Briseno said.
They believe the birds are moving to the area later in the season this
year, and for the most part, the flock that is here stays in Grand
Island the majority of the year.
"If we start to see an increase in the number of birds and
complaints, we will once again initiate the same program as we have in
past years," Briseno said.
HBCC UFO Research
Wed, 21 Jan 2009 01:52 UTC
Date: January 20, 2009
Time: 8:15 p.m.
Number of witnesses: 1
Number of objects: N/A
Shape of objects: N/A
Full Description of event/sighting: Last
night, Tuesday, January 20th, 2009, I was riding with my wife in Tarpon
Springs, Pinellas County, Florida. We were facing west driving just
east of US19. I saw a bright, almost neon blue flash in the sky, high
above the clouds which stretched from as far left as I could see to as
far right as I could see.
There was sporadic cloud cover but the flash
illuminated the sky for 3-5 seconds. I have since wrote my friends,
wrote my local news program tip line (www.baynews9.com) and have not
seen anywhere else that another sole saw this flash. That is until I
googled and saw reports of a similar incident last week in
Indianapolis. There were trees far in front of me and far to the right
and left so I could not see any main stream of light extending to the
ground as reported in Indianapolis. What I saw, however, was the entire
sky above the clouds to my west (I was driving west) illuminate for 3-5
seconds in such a bright and beautiful deep blue.
Experts say a meteor that lit up the sky over Alberta likely burned up before reaching the ground.
The bright flash of light was spotted all over northeastern Alberta around 8 p.m. Tuesday.
"I was just out for an evening walk ... and I saw it going across the
sky and it was dropping," said Lana Goguen of Bonnyville. "It was still
quite a distance away south of Bonnyville. As it was streaking through
it was kind of an orangy-reddish colour and it had a small trail, but
it wasn't the long, streaking trail."
The Royal Astronomical Society of Canada's Bruce
McCurdy said he received several reports as well, from Edmonton and
Vegreville.
"We got some pretty decent reports from knowledgeable
observers who said it was a very nice, bright meteor, bright enough to
be classified as a fireball - meaning as bright or brighter than Venus,
but only about that bright - and almost certainly not something
associated with anything big enough to make it to the ground," he said.
Both McCurdy and Goguen said the meteor, while impressive,
paled by comparison to the one that lit up the Alberta sky before
thousands of its pieces landed around the Saskatchewan-Alberta border
in November.
"It wasn't as bright," Goguen said. "I don't think it was as
big, but it was big enough that it was well and clearly visible to the
naked eye."
Meteorite News
Sat, 24 Jan 2009 06:56 UTC
Fireball sighting:
Observers in Massachusetts and Rhode Island are reporting a "huge,
pulsating blue-green fireball" sighted within minutes of 8:48 pm EST on
Jan. 23rd. It was bright enough to be seen through heavy cloud cover,
according to one witness.
Source: Robert Woolard, USA
Masspike fireball: Last night a meteoroid
of unknown size hit Earth's atmosphere over New England. Its bright,
blue-green disintegration startled motorists driving along the
Massachusetts Turnpike and surrounding areas: eye-witness accounts.
Eyewitness Accounts:
Location: near Auburn Massachusetts
Comments: James Vasalofsky: "I saw the fireball on 1/23/09 around
8:48pm. It was blue-ish green when it first appeared, then it was a
bright light that lasted about 2 seconds. I was on the Mass Pike
heading East near Auburn and it was off to the right in the direction
of the South. It was an amazing sight! I've seen meteor showers before
but this seemed really close. I assume it was a meteor."
Location: Foxboro, Massachusetts
Comments: Robert Russell: "I was driving home with my family at
about 9pm on Friday, Jan 23rd, and we saw what looked to be a huge
fireball coming straight down from the black sky. All four of us saw
the same thing and were all shocked. It was much bigger than a typical
shooting star and was certainly going straight down as opposed to
shooting horizontally across the sky. It had blue and green colors in
it too. It appeared to have landed or struck down just north of Rt 495
and just east of Rt 95 somewhere in Foxboro or Mansfield."
Location: Lexington, Massachusetts
Comments: Mark A. Abel: "On January 23 at 8:48PM EST I was
traveling on I-95 South bound in the Lexington area near the Hanscom
Airfield when I saw the bluish-green fireball out of the corner of my
eye. At first I thought I may had caught a glimpse of an airplane
landing flood light since I was in the Hanscom Airfield area but then
it emerged from behind the low level clouds again and I could see that
it indeed was a brilliant fireball."
Location: Wakefield, Rhode Island
Comments: Donna & Randy Swanson: "We observed a huge pulsing
blue green fireball through the clouds tonight @ 8:48 PM dropping past
the horizon, due NE into the Atlantic ocean towards Cape Cod. Bright
enough to be seen through heavy cloud cover!"
Location: Agawam, Mass.
Comments: John B Byerly: "At 8:50 pm from Agawam Massachusetts
looking easterly I saw a blue green fire ball through a pretty thick
cloud cover. It lasted maybe a second with a significant tail. I am a
total amateur but It looks similar to the video that was posted a
couple of days ago."
Location: North Windham, Connecticut
Comments: Paulette Harwood: "My husband and I observed the fireball
while heading southeast on Rt. 6 in North Windham, CT. It was quite
large and had a green glow."
Location: MassPike between exits 11 and 11A
Comments: E. Szymczak: "I was driving east on the MassPike and at a
few minutes before 9 between exits 11 and 11A and saw a huge green
fireball that appeared to come from the north fairly close to the
horizon. It was spectacular!"
Location: Warwick, Rhode Island
Comments: Joe Malachowski: "My son and I saw the fireball at 8:48pm
on 1.23.09 in Warwick, Rhode Island. It was blue-green and lasted
approximately 3 seconds - ended without a flash. This was the brightest
meteor I've seen in my 46 years, brighter even than the one I saw at
the Grand Canyon 2 years ago."
Location: Little Compton, Rhode Island
Comments: Anthony Russi: "I was sitting in my den and through my
window I saw a dazzling fireball drop from the night sky. I live in
little Compton, Rhode Island on the Sakonnet River, the object was east
of me. It came straight down and looked like huge flare. Sometime
around 8:30."
Location: Connecticut
Comments: Briana: "At approx. 8:45pm, our family was driving north
on route 395 between route 97 & 169 in CT. My husband said, 'Look,
Look, Look!!' And there, straight ahead, was a very bright object
heading for the ground. For me it was gone quickly, but my husband said
he saw it above the clouds, then it disappeared for a moment behind
some clouds, then he saw it again below the clouds. Because of this we
both think it had to have hit the ground. Most likely someplace in NE
CT, possibly between Danielson and Thompson. It was very cool, but I
hope no one was hurt."
HBCC UFO Research
Sat, 24 Jan 2009 17:33 UTC
Brian Vike
Date: January 15, 2009
Time: Approx: 9:30 p.m.
Location of Sighting: about 20 miles north of Indianapolis while traveling north on I-69
Number of witnesses: 2
Number of objects: 0
Shape of objects: 0
Full Description of event/sighting: While
driving northbound on I-69 with my girlfriend we noticed the western
sky suddenly lit up a greenish color. We did not see any objects or
hear any sounds, just the sudden brightness of the sky.
We were roughly 20 miles north of Indianapolis to the
best of my knowledge. I am not sure if there is anything in the
proximity of the area to create such a brightening of the night sky. We
really did not think about it until reading the report of the girl who
saw something similar two nights earlier. Although she reported
something blue or turquoise this was definitely greenish. It was very
strange but not intimidating in anyway.
Date: January 10, 2009
Time: 8:00 to 100:00 p.m.
Number of witnesses: 7
Number of objects: 1
Shape of objects: Round
Weather Conditions: Clear night with a full moon
Description: Was looking out the window
and saw a ball of fire moving across the sky. At first I thought it was
a helicopter or a plane that was on fire. I went out on the deck in my
sock feet to see it, but didn't stay out to watch because it was too
cold out. The light didn't fade in intensity or make any noise and it
was very strange.
TV/Radio: I did call someone from local TV and am waiting for them to call me back today to see if there have been any other sightings.
Thank you to UFOINFO for this report. http://www.ufoinfo.com/
Newly-discovered asteroid 2009 BD is slowly passing by Earth today only
400,000 miles away. The small 10m-wide space rock poses no threat, but
it merits attention anyway. The orbit of 2009 BD appears to be almost
identical to the orbit of Earth. 2009 BD may be a rare co-orbital asteroid,
circling the sun in near-tandem with our planet. Extrapolating the
motion of 2009 BD into the future, we see that it remains in the
vicinity of Earth for many months to come, never receding farther than
0.1 AU (9.3 million miles) until Nov. 2010. Future observations may
reveal the nature of this strange asteroid; stay tuned! [3D orbit] [ephemeris]
San Francisco Examiner
Sun, 25 Jan 2009 19:51 UTC
Patricia Phillips
© NASA
There's a newly-discovered weird asteroid kid on Earth's block, and it's moved in close. Really, really close, in space terms.
Asteroid 2009 BD is cruising by us today at a distance of only about 400,000 miles, according to NASA's Near Earth Object Program. This strange asteroid is estimated to be 5. 7 meters to 13 meters in diameter.
Astronomers will be studying 2009 BD with great interest, because it
may be a very rare coorbital asteroid. In 2006, NASA's Dr. Tony
Phillips explained how these type of asteroids corkscrew as they move
in tandem with Earth:
These asteroids are called Earth Coorbital Asteroids or
"coorbitals" for short. Essentially, they share Earth's orbit, going
around the Sun in almost exactly one year. Occasionally a coorbital
catches up to Earth from behind, or vice versa, and the dance begins:
The asteroid, while still orbiting the sun, slowly corkscrews around
our planet.
Sometimes, coorbitals hang around for awhile:
2004 GU9 is perhaps the most interesting. It measures about2009 BD will be in Earth's neighborhood for awhile,
200 meters across, relatively large. And according to calculations just
published in the Monthly Notices of the Royal Astronomical Society (S.
Mikkola et al., 2006) it has been looping around Earth for 500
years--and may continue looping for another 500. It's in a remarkably
stable "orbit:.
giving scientists a change to evaluate it, and its path. The Jet
Propulsion Laboratory (JPL) has an applet that shows the asteroid's orbit.
What else is going on in our neck of the woods? Earth's Busy Neighborhood offers a traffic report.
Chicago Chronicle
Mon, 26 Jan 2009 16:30 UTC
Steve Koppes
© NASA
Steve
Simon and Lawrence Grossman of the Geophysical Sciences Department
analyzed some of the first samples of a comet ever returned to Earth by
a spacecraft. The artist’s rendering above shows the Stardust
spacecraft during its close encounter with comet Wild 2, during which
the samples were collected.
Steve
Simon and Lawrence Grossman of the Geophysical Sciences Department
analyzed some of the first samples of a comet ever returned to Earth by
a spacecraft. The artist’s rendering above shows the Stardust
spacecraft during its close encounter with comet Wild 2, during which
the samples were collected.
University cosmochemists
Lawrence Grossman and Steven Simon have studied scores of meteorites
during their careers, with a few Apollo lunar samples thrown in for
good measure. But until 2006, they had never before examined a verified
sample of a comet.
Much to their surprise, what they found looked a lot like components of some of the meteorites in their research collection.
"The thing that strikes me about the sample is how similar the
mineral identities and the chemical compositions are to the things that
we find in carbonaceous chondrites," said Grossman, Professor in
Geophysical Sciences and the College.
These meteorites contain material that has been unaltered
since the birth of the solar system 4.5 billion years ago. The cometary
grains differ from carbonaceous chondrites in their complete lack of
water-bearing minerals, however.
The comet samples that Grossman and Simon examined
were among thousands of dust particles that NASA's Stardust spacecraft
collected from Comet Wild 2 in January 2004. Two years later, Stardust
became the first mission to return samples of a comet to Earth.
Stardust was scientifically important because comets are
usually out of reach, Grossman said. And yet, aside from the sun, they
may be the most abundant material in the solar system. "There may be more stuff in the comets than in all the planets put together," he said.
Grossman and Simon were among the 75 co-authors who published the first
analysis of the comet Wild 2 particles in the Dec. 15, 2006 issue of
the journal Science.
The Chicago scientists and 10 co-authors will present new Wild 2 data
in the November 2008 issue (expected to be published early this year)
of Meteoritics and Planetary Science.
The tiny cometary particles enabled Grossman, Simon and their
colleagues to track the violent convulsions in the giant cloud of gas
and dust that gave birth to the solar system. The convulsions flung
primordial material billions of miles from the hot, inner regions of
the gas cloud, which later collapsed to form the sun, out into the
cold, nether regions of the solar system. There they became
incorporated into an icy comet.
The team identified three particles described in the Meteoritics
study as pieces of a shattered refractory inclusion, one of the most
unusual and informative materials discovered in early analyses of the
Wild 2 samples. Such inclusions, found in some meteorites, formed by
condensation from the gaseous cloud that formed the sun at temperatures
of more than 2,500 degrees Fahrenheit early in the history of the solar
system.
"If you take a gas of solar composition and let it cool down,
the very first minerals to solidify are calcium- and aluminum-rich,"
said Simon, Senior Research Associate in Geophysical Sciences. Wild 2
contains these and other minerals formed at high temperatures.
"That's an indication of transport from the inner solar system
to the outer solar system, where comets are thought to have formed," he
said.
Either turbulence within the nebula, or a phenomenon called
bipolar outflow from the early sun could account for the long-distance
transport of cometary material, according to Simon and his Meteoritics co-authors.
Bipolar outflow results when the rotating disks that surround
developing new stars jet gas from their polar regions, which
astronomers have observed telescopically. "That's part of the so-called
X-wind model, which is somewhat controversial," Simon said.
The controversial aspect of the X-wind model is the claim that
the process would produce the kind of granules that Simon and his
colleagues have now identified in comet Wild 2. Another less likely
possibility: The cometary material in question may have formed around
another star of composition similar to the sun, then drifted into the
outer reaches of the solar system. There it became incorporated into
comet Wild 2.
Scientists organized the Stardust mission expecting that Wild
2's samples would reveal a bonanza of exotic minerals, including debris
from ancient, distant stars that had met their demise long before the
birth of the sun. They may now need to rethink how comets formed,
Grossman said.
"Because they're loaded with ices, we've always thought that
these are outer solar system objects," he said. "But maybe cometary
ices formed much closer in, after the inner part of the solar nebula
cooled off, and incorporated the high-temperature stuff that formed
earlier."
HBCC UFO Research
Mon, 26 Jan 2009 20:43 UTC
Brian Vike
Date: January 25, 2009
Time: 8:00 p.m.
Number of witnesses: 2
Number of objects: 1
Shape of objects: Circular.
Full Description of event/sighting: From
my living room window I saw a very bright orange/yellow light in the
sky. It was moving steadily northwards. I went outside to get a better
look. Difficult to estimate height/distance/speed as it was pitch
black. I would estimate at least a few thousand feet up, speed stayed
constant.
There was no cloud cover. I watched until it
disappeared over rooftops of the houses at the end of the road. It made
no sound. My first impression was of a meteor or some space debris
skimming the atmosphere and burning up. The object was very bright, you
know when your eyes sort of tell you that you are looking at something
very bright?
© Unknown
Halley's Comet
Halley's Comet
Rome - An Italian astronomer has kept up an amazing spotting streak with his ninth comet in just over a year.
Andrea Boattini, who broke the 150-year-old Italian record for comet
spotting with seven last year, said he spotted the new body in the
early hours of the night while he was scanning all the Near Earth
Objects (NEOs) currently visible.
''I wasn't too sure it was a comet straight away because it
was hazy but the skies cleared a bit later and allowed me to confirm
the comet's nature,'' said Boattini, 39, who works at the Mount Lemmon
Observatory in Arizona on a NASA programme to identify objects that
could potentially pose a threat to the Earth.
The new comet has the technical tag C/2009 B1 but like the others has also been given its discoverer's name.
It belongs to the so-called Jupiter family, is in the Andromeda
constellation, and approaches Earth once every 17 years, Boattini said.
''It will be observable for another two months, with a medium-sized telescope,'' he said.
Boattini also has 170 asteroids under his belt and recently
burnished his reputation further by finding the closest of those rocks
to the Sun.
The scientist is an expert in asteroids and comets.
He specialises in NEOs, of which there are four groups.
His latest asteroid was one of the very rare IEOs (Inner Earth Objects).
Asteroids and comets are both bits of space rock. The main visual difference between them is that comets have a tail.
Asteroids, which are dimmer, are found in belts that orbit the
Sun, while comets have larger orbits and some pop out of the Solar
System.
Two of the brightest and best-known comets are the Hale-Bopp Comet and Halley's Comet.
Le Mars Daily Sentinel Blog
Thu, 29 Jan 2009 16:25 UTC
Magdalene Landegent
Did anyone else see the crazy falling star on Wednesday night?
I was driving into Le Mars from the north, and when I was about a mile out of town, I saw a giant blue-green falling star with some white flecks, which looked like it was headed straight for my little house.
Quickly in my mind I tried to run through the list of things covered
under renter's insurance. I don't recall "meteor shower blast" being
listed...
Luckily, it seemed to burn out before that - plus it was probably hundreds of miles away.
What was that thing?
© BBC News
Woolly mammoths were not the only ones to die out 13,000 years ago.
Woolly mammoths were not the only ones to die out 13,000 years ago.
A
study of wildfires after the last ice age has cast doubt on the theory
that a giant comet impact wiped out woolly mammoths and prehistoric
humans.
Analysis of charcoal and pollen records from around 13,000 years ago
showed no evidence of continental-scale fires the cometary impact
theory suggests.
However, the results showed increased fires after periods of climate change.
The research is published in the Proceedings of the National Academy of Sciences.
The cometary impact hypothesis holds that an enormous comet
slammed into or exploded over North America in the Younger Dryas period
some 12,900 years ago.
The idea was first mooted by Richard Firestone of Lawrence Berkeley Laboratory in the US and colleagues in 2007.
The impact, they argue, would have unleashed a shock wave and
ignited fires spanning the entire continent. That in turn would explain
a number of other observations.
For instance, the wildfires would have burned all the plant
matter in their wake, effecting the evident end of the prehistoric
Clovis culture of humans.
The lack of vegetation would also have contributed to the
extinction of the "megafauna" - large animals such as woolly mammoths
and mastodons - that disappear from the fossil record around that time.
But the theory has inspired a degree of scepticism in the
palaeontology community, and many suggest that much more data is needed
to prove or refute it.
"The claim of course makes good headlines: 'Cometary impact
kills the mammoths', but I'm not sure it's quite like that," said
Andrew Scott of Royal Holloway, University of London, a co-author on
the new research.
"Even if you have cometary impact data, that doesn't imply they generated wildfires that killed off the mammoths.
"What we've always needed was a way to test the hypothesis. This is the
first chance to test it with all the records that we've had across
North America."
Professor Scott and the rest of a team including the Global
Palaeofire Working Group analysed the well-preserved charcoal and
pollen layers beneath lakes and in peat bogs across the continent.
These layers of sediment read like a history book of each
region, with thousands of years of climate and wildfire history laid
out by depth.
By correlating the ages of different layers from different
regions using radioisotope analysis and matching those up with more
recent data like that from tree rings, the history book yielded up a
number of interesting results.
One of them is that while there was significant evidence of
localised fires throughout a 5,000-year period centred around the
Younger Dryas, there was no sign of a single, continental-scale
wildfire event.
The finding does not refute the possibility of comet strikes
in the past, Professor Scott notes, but casts serious doubt on the
grand scale wildfires that would have wiped out whole species and
cultures.
Moreover, it is not the only thread of evidence that has been called into question in the debate.
Most recently, those involved in the impact theory point to
nanometre-scale diamond samples found in a sediment layer corresponding
to the time of the impact, but Wallace Broecker of the Lamont-Doherty
Earth Observatory (LDEO) at Columbia University points out that such
nanodiamonds have been found in modern peat bogs.
© Getty Images
Scenes like this become more common after abrupt climate change.
Scenes like this become more common after abrupt climate change.
"One
by one, every piece of evidence they [comet hypothesis proponents] have
presented is going to fall," Professor Broecker told BBC News.
"But one of the stronger ones was this fire stuff, so this hits right at the heart of their argument."
The problem, Professor Scott says, is that the impact
hypothesis has made many people focus on just one page of the
sedimentary history book: the layer from 12,900 years ago.
"When you concentrate on one layer so intensely, you find all sorts of things which you think are unique," he added.
Richard Firestone, commenting on the work, does not believe it
presents a serious challenge to the impact theory - in fact, he argues
that they are in agreement.
"Their data is too low resolution to say much about what happened 12,900 years ago," he told BBC News.
"The paper merely shows that fires increased near the onset of the
Younger Dryas and continued for some time. These results are in
complete agreement with what we observed."
Of more importance to current climate watchers is the finding
that during the 5,000-year period studies, the greatest incidence of
fires occurred just after periods of abrupt climate change.
While the idea that periods of warming would be followed by
periods of high fire occurrence is not new, the result is the first
evidence-based proof of the connection.
Periods of climate change result in the death of plants and trees that more readily provide fuel.
The recent report in the journal Science of forests in the
western US dying faster as temperatures rise is another sign that we
may be entering a period of significant wildfire increase.
"One of the issues that concerns me is that there are many
parts of the world, like Britain, where there's not naturally a lot of
wildfire, so we're not prepared for it," said Professor Scott.
"There's no contingency, no thinking ahead of what might happen; climate change has significant impact other than just rising sea levels."
© Giovanni Sostero and Ernesto Guido, Remanzacco Observatory
Comet Lulin as seen on 2 January 2009. The image shows both the tail and the anti-tail.
Comet Lulin as seen on 2 January 2009. The image shows both the tail and the anti-tail.
Late next month Earth will receive a new celestial visitor named
Lulin - or Comet C/2007 N3 - which astronomers say may have never
visited this corner of the solar system before and should be visible to
the naked eye.
Comets are icy clumps of dust and small rocks left over from
the beginnings of the solar system. As they near the Sun some of the
outer layer of ice is vaporised, releasing gas and solid debris that
fans out into a tail pointing directly away from the Sun.
Astronomer and author Gary Kronk, based in St Jacob, Illinois,
estimates that by 24 February, Lulin's gas tail should appear as long
as around eight times the diameter of a full Moon. At that time it will
be a mere 38 million miles from Earth, almost as close as Mars reaches
to our planet.
First time visitor?
By tracking Lulin since its discovery in the summer of 2007,
astronomers have calculated that it had already been on the move for 10
million years before it arrived in the solar system. They
say that either Lulin was once here 10 million years ago, or it was
somehow knocked out of the Oort cloud of billions of comets that
surrounds the solar system and has never entered the inner solar system
before.
"If this is its first approach towards the Sun, we don't know how it
will respond. Some comets become brighter than expected and some
don't," explains Kronk.
Lulin's brightness depends on how much the Sun can melt the comet's hard icy coat to release a visible tail of debris.
A comet on its first approach to the Sun can resist its heat,
preventing a bright tail from appearing. But Kronk thinks Lulin will
get close enough to our star to make that unlikely. He is confident
that the comet will be visible with the naked eye, registering
magnitude 5 on the standard brightness scale, where 6 is the faintest.
"This is what makes comets so amazing," he told New Scientist.
"Every comet has its own personality. No-one knows exactly what the
comet is going to do." Lulin will be moving fast enough to appear to be
creeping across the background of more distant stars, he adds.
© Ligustri Rolando, Circolo Astrofili di Talmasson
Comet Lulin on 23 January.
Comet Lulin on 23 January.
Twin-tailed comet
Lulin could also be one of only a few comets that appears to
have two rather than one tail. The extra "antitail" becomes visible
because Earth happens to be orbiting the Sun on the same plane as
Lulin.
When solar wind blows gas and dust particles away from a
comet, larger debris moves more slowly and lags behind the moving
comet. The fanned tail appears to extend from both sides of the comet's
body when viewed from the edge on.
The last comet with a visible antitail was Arend-Roland in
1957, says Kronk. "Lulin could give the best chance in my lifetime to
see something like that," he adds.
Professional astronomers are also looking forward to Lulin's
visit. Michael Mumma, director of the Goddard Center for Astrobiology,
Maryland, and colleagues have scheduled three months of observations,
starting next week, at the Keck telescopes on the summit of the Mauna
Kea volcano in Hawaii.
By analysing the light from Lulin they hope to detect the
hydrogen isotope deuterium, to strengthen their hypothesis that icy
comets delivered some of the Earth's water during the first billion
years after its formation.
UFOINFO
Thu, 29 Jan 2009 18:01 UTC
Date: January 9, 2009
Time: 6:30 to 7:00 p.m.
Number of witnesses: 2
Number of objects: 1
Shape of objects: Looked like a rocket engine.
Weather Conditions: Cold, Dark and clear.
Description: Driving the kids home on
Friday night we were talking about the recent wind turbine reports ( 7
year old son, first real encounter with UFO's in the media ). As we
were talking what looked like a afterburner of a plane engine ignited
and flew parallel to the car for around 5 seconds before fading from
site.
The object was flying away from Tickton village
towards Beverley. I put the car window down as I saw the object and
didn't notice any noise at all, certainly no engine noise and we are
often on the path of military jets.
The flames were coloured from blue to yellow and a hundred
meters or so to our left and looked to be around 5 meters in length at
that distance.
Never seen anything like it and not the normal firework
trajectory, this ignited high in the air parallel to us and flew away
from us ( in the same direction we were travelling ) at speed. My son
saw the same thing from the rear of the car.
1 comment:
Hi, we're producing a movie about the asteroid prediction of Jimi Hendrix - "Remote View Mutation" - based on the book "Rock Prophecy"
http://www.rockprophecy.com/remote.html
The rockprophecy.com website chronicles escape haven plans for the global elite who're spining bogus science for the world's most controlled story - the coming rock impact. Mogul media has been able to portray the 2004 tsunami as an earthquake event, rather than the meteor impact that it was.
Some of these webpage chronicles are similar to yours:
http://www.rockprophecy.com/rocknews.html
http://www.rockprophecy.com/time.html
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