[meteorite-list] New, long, Carancas article II

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Fri, 4 Apr 2008 20:33:09 -0500
Message-ID: <05fc01c896bd$01811040$8250e146_at_ATARIENGINE>

Hi, List,

    Peter Schultz's paper on Carancas, which is what the
college newspaper article is trying to summarize, can be
found, in its entirity, here:
http://www.lpi.usra.edu/meetings/lpsc2008/pdf/2409.pdf

    Jerry wrote:
> Just what Sterlng has been proposing
> for the last few months.

    Schultz and I both agree that a greater aerodynamic
efficiency will get a chondrite to the ground faster with
less loss of material, making an impact like Carancas
possible.

    What Schultz proposes is that the fragile material of
Carancas fragmented early on but did not "pancake" out
and cause an airburst, but was wrapped by the shock wave
around the hypersonic meteoroid into a "bullet" shape
that stayed together and kept its high speed to the ground.

    His explanation is perfectly feasible, and that may happen
with any weak stone. He relates the idea to the characteristics
of small craters on Mars which do not resemble the small
impact craters we're used to on Earth (but do resemble
Carancas):
    "Current missions are discovering small (20 m) craters
with blast zones, blocky rays, and near-rim ejecta. Prior
studies have emphasized the important collective contribution
of small-size meteorites and impact melt to the surface."

    What I proposed was that the Carancas impactor was an
elongated fragment to begin with. That is, it was a "sliver" of
asteroid that was 4 or 5 times longer than its width when it
entered the Earth's atmosphere. The results would be the
same: a faster trip to the ground in (mostly) one piece.

    My Old Buddy Bill Occam (otherwise known as the
medieval philosopher William of Occam, 1288-1347 AD)
always says, "one should always opt for an explanation
in terms of the fewest possible number of causes, factors,
or variables." In other words, the simplest explanation
that explains everything is the best one.

    Well, OK. What Bill actually said was, "Entia non
sunt multiplicanda sine necessitate," but he talks funny,
you know.



Sterling K. Webb
------------------------------------------------------------------------
----- Original Message -----
From: "Jerry" <grf2 at verizon.net>
To: <cynapse at charter.net>; <meteorite-list at meteoritecentral.com>
Cc: <meteoriteguy at yahoo.com>
Sent: Friday, April 04, 2008 2:39 PM
Subject: Re: [meteorite-list] New, long, Carancas article


"It's like having a Volkswagen turn into a
Ford Taurus," Schultz said, adding
that this sort of reshaping is well known
to geologists who study islands and
land-water interaction. "If you put a big
pile of dirt in a stream, that mound
will eventually turn into a teardrop shape.
It's trying to minimize the friction."

Just what Sterlng has been proposing
for the last few months.

Jerry Flaherty
----- Original Message -----
From: "Darren Garrison" <cynapse at charter.net>
To: <meteorite-list at meteoritecentral.com>
Cc: <meteoriteguy at yahoo.com>
Sent: Friday, April 04, 2008 12:25 PM
Subject: [meteorite-list] New, long, Carancas article


> Hey, Mike, did you know that you and your team of poachers recovered 10
> kilos of
> Carancas?
>
> http://media.www.browndailyherald.com/media/storage/paper472/news/2008/04/04/Features/Professor.Solves.A.Meteor.Mystery-3304236.shtml
>
> Professor solves a meteor mystery
> By: Chaz Firestone
> Posted: 4/4/08
> Last September, something strange landed
> near the rural Peruvian village of
> Carancas. Two months later, so did Peter Schultz.
>
> One was an extraterrestrial fireball that struck the Earth at 10,000 miles
> per
> hour, formed a bubbling crater nearly 50 feet wide and afflicted local
> villagers
> and livestock with a mysterious illness. The other is the Brown geologist
> who
> may have figured out why.
>
> The fiery mass shot across the morning sky bursting and crackling like
> fireworks, villagers said after the Sept. 15 impact. An explosive crash
> tossed
> nearby locals to the ground, shattered windows one kilometer away and
> kicked up
> a massive dust cloud, covering one man from head to toe in a fine white
> powder.
> Many thought the streaking fireball - brighter than the sun, by some
> accounts -
> was an aerial attack from neighboring Chile.
>
> Curious shepherds and farmers approached the crash site to find a smoking
> crater
> reminiscent of a Hollywood film, laden with rocks and stirring with
> bubbling
> water that emitted a foul vapor. But curiosity turned to fear when
> unexplained
> symptoms began to crop up in Carancas: headaches, vomiting and skin
> lesions
> struck more than 150 villagers, Peru's Ministry of Health stated days
> later.
> Locals reported that their animals lost their appetites and bled from
> their
> noses. Children were restless and cried through the night.
>
> But according to Schultz, the professor of geological sciences who visited
> the
> site last December, the true mystery in Carancas is how any of this
> happened in
> the first place.
>
> Sophisticated theory and conventional wisdom have long agreed that most
> meteors
> break into fragments and fizzle out before they can reach the Earth's
> surface.
> Even those large and durable enough to make it through the atmosphere hit
> the
> ground as ghosts of their former selves, "plopping out of the sky and
> forming a
> bullet hole in the Earth," Schultz said. "This meteor crashed into the
> Earth at
> three kilometers per second, exploded and buried itself into the ground."
>
> Last month, Schultz delivered a highly anticipated lecture at the 39th
> Lunar and
> Planetary Science Conference in League City, Texas. And if he's right, the
> bold
> theory he proposed there may shake loose a "gut response" entrenched
> within the
> geological, physical and astronomical sciences: "Carancas simply should
> not have
> happened."
>
>
>
> A Web of speculation
>
> The handful of shepherds who happened to lead their Alpaca herds near the
> arroyo
> that day may have been the first humans ever to witness an explosive
> meteor
> impact. But the rest of the world quickly got its chance, if vicariously,
> through a flurry of activity in the blogosphere.
>
> Hundreds of scientists, journalists and captivated amateurs weighed in on
> the
> bizarre events as they unfolded, offering scores of pet theories and
> radically
> revising them as more information streamed in from Peru.
>
> Pravda, a Russian online newspaper born out of a print version run by the
> country's former Communist Party, ran the headline "American spy satellite
> downed in Peru as U.S. nuclear attack on Iran thwarted" five days after
> the
> impact. The story attributes the villagers' illness to radiation poisoning
> from
> the satellite's plutonium power generator.
>
> Other proposed explanations were less sensational. Nevadan wildlife
> biologist
> and amateur geologist David Syzdek wrote a Sept. 18 blog post titled
> "Meteorite
> strike in Peru gassing villagers? Maybe not." In it, he proposed that a
> mud
> volcano producing toxic gases was responsible for both the illness and the
> crater.
>
> "The Andes are very active geologically so I think there is a good
> possibility
> that this crater was caused by an outburst of geothermal activity," he
> wrote.
>
> As for the blinding light shooting across the sky, Syzdek chalked it up to
> coincidence.
>
> "Fireballs are quite common," he wrote. "One possible scenario is that the
> people who saw the fireball just happened on a recently formed mud volcano
> while
> they were out looking for the fireball impact site."
>
> Though Pravda and Syzdek drew radically different conclusions from the
> reports,
> what they shared with each other, many bloggers and even some scientists
> was a
> healthy skepticism about reports coming out of Peru. Pravda and Syzdek
> both
> pointed out in their posts that an explosion powerful enough to create
> such a
> large crater would be equivalent to 1,000 tons of TNT, or a tactical
> nuclear
> strike.
>
> "When I first saw the news reports, they just didn't seem right," Syzdek
> later
> said in an interview. "Explosive impacts like this just don't happen."
>
>
>
> 'A hyperspeed curveball'
>
> Gonzalo Tancredi, a Uruguayan astronomer who collaborated with Schultz in
> Carancas, said initial reports of the impact confounded amateurs and
> Ph.D.s
> alike. Bewildered scientists even entertained the possibility of a hoax as
> rumors floated around the scientific community.
>
> "At the beginning, there were some doubts about what really happened
> there,"
> Tancredi said. "We thought maybe it was a meteor fall or maybe it was
> something
> else, even something fake."
>
> But when Tancredi visited Carancas a few weeks later, what he observed
> silenced
> the conspiracies and pointed unequivocally to one conclusion.
>
> Tancredi interviewed locals, who reported a large mushroom cloud that
> formed
> over the crater and compression waves that knocked villagers to the
> ground. He
> also found pieces of soil and rock that had been launched over three
> football
> fields from the crater - one piece even pierced the roof of a barn 100
> meters
> away. Combined with analyses of infrasound detectors and the patterns of
> crater
> "ejecta," the evidence pointed to a genuine and very powerful meteorite
> impact.
>
> But the question that remained on everyone's mind was how the meteor got
> there
> at all - a scientific riddle that was made even more challenging by
> Michael
> Farmer.
>
> Farmer is a controversial figure in the geological community. He is a
> meteorite
> hunter, a poacher of alien rocks who travels to impact sites around the
> world -
> usually the "bullet hole in the Earth" type mentioned by Schultz - and
> collects
> whatever he can find, often brushing up against authorities and other
> hunters.
> Meteorite hunting is Farmer's full-time job; he profits from selling what
> he
> finds.
>
> Farmer, who said he is "totally self-taught" when it comes to meteors,
> said he
> was as skeptical as the rest when he first heard the reports coming out of
> Peru
> while on hunt in Spain. But 16 days later, he and his partners found
> themselves
> staring into the Carancas impact crater, the first Americans on the
> scene - and
> they stumbled on an extraterrestrial gold mine.
>
> "We got there and just started picking up pieces off the ground," Farmer
> said.
> "The entire ground was white, just white powder which was all meteor."
>
> Farmer and his team eventually accumulated 10 kilograms of small meteorite
> fragments and sold them to private collectors and universities for an
> astronomical $100 per gram.
>
> But despite his rocky past with the geological community, Farmer and his
> expensive fragments made a priceless contribution to scientists. Within
> minutes
> of arriving on the scene, Farmer discovered that the Carancas meteorite
> was a
> chondrite, or stony meteorite, as opposed to an iron meteorite.
>
> Though far more common than iron meteorites, chondrites are highly
> vulnerable to
> ablation - the cracking, eroding and even exploding that occurs when a
> meteor
> enters the atmosphere and undergoes extreme changes in temperature and
> pressure.
> As a result, chondrites are far less likely than the more durable iron
> meteorites to make it to the Earth's surface in large pieces - which makes
> the
> Carancas meteorite all the more baffling.
>
> "For a while, the only information we were getting was from Farmer's Web
> site,"
> Schultz said. "This was not the type of object you'd expect to get through
> the
> atmosphere in a tight clump."
>
> With most pieces of the geological puzzle on the table, the stage was set
> for
> Schultz to visit the site for himself. But when he arrived there in
> December
> with a Brown graduate student, Tancredi and Peruvian astrophysicist Jose
> Ishitsuka, a budding geologist actually made the crucial discovery. Scott
> Harris
> GS said he collected some soil samples "initially out of curiosity" to
> look for
> evidence of shock deformation, which occurs when an object rapidly
> decelerates
> in cases like impacts or explosions. When Harris looked at the material
> under a
> microscope, he found tiny mineral grains that had turned into glass
> because of
> heat and massive shock forces, indicating a very high-speed impact. Here
> was yet
> another mystifying piece of evidence.
>
> "At the minimum," Harris said, "this would support a velocity of three
> kilometers per second - a real high-velocity explosion instead of just a
> plop in
> the ground."
>
> By this time, more reputable scientific theories of the impact had
> supplanted
> the initial speculation, the most popular of which came from a group in
> Germany
> and Russia. They proposed that the meteor entered the Earth's atmosphere
> at a
> very shallow angle, allowing it to reach the surface gradually and avoid a
> sudden increase in pressure - "the difference between diving in and doing
> a
> belly flop," Schultz said.
>
> But their theory's relatively low impact velocity of 180 meters per
> second, or
> about 400 miles per hour, was consistent with every piece of evidence but
> Harris', which pointed to a velocity of about 10,000 miles per hour at
> impact.
>
> "This was nature's way of throwing us a curveball," Schultz said. "A
> hyperspeed
> curveball."
>
>
>
> Changing shape, changing theory
>
> Back home in Providence, Schultz was now faced with the task of fitting
> the
> puzzle pieces together into a cohesive theory. And to do it, he looked to
> Earth's closest planetary neighbor, Venus.
>
> "Our models make predictions about what kind of objects can make it to the
> surface at what velocity, and the Carancas meteor isn't usually one of
> them,"
> Schultz said. "But Venus has a much denser atmosphere and we still find
> craters
> on its surface. How did they get there? I think it might be the same thing
> here."
>
> To explain the alternative theory he developed, Schultz compared a typical
> meteor's descent to a waterskier behind a boat.
>
> "Normally when you're on the outside of the wake, you're pushed out
> further,"
> Schultz said. "From my experience looking at Venus, I realized that there
> was a
> certain condition where the waterskier will stay inside the wake, and
> actually
> get pushed inward."
>
> At last month's Lunar and Planetary Science Conference, Schultz proposed
> that
> the meteor did break up into pieces, but shock waves created by the
> speeding
> mass may have kept them close together. And since the meteor descended as
> a
> clump of fragments instead of one large piece, it reshaped itself along
> the way
> to become more aerodynamic, like a football or a javelin cutting through
> the air
> instead of a poorly shaped hunk of rock.
>
> "It's like having a Volkswagen turn into a Ford Taurus," Schultz said,
> adding
> that this sort of reshaping is well known to geologists who study islands
> and
> land-water interaction. "If you put a big pile of dirt in a stream, that
> mound
> will eventually turn into a teardrop shape. It's trying to minimize the
> friction."
>
> Tancredi, who co-authored the paper with Schultz, Harris and Ishitsuka,
> said
> Schultz's theory is gaining popularity but is still being debated, even
> among
> the group that proposed it.
>
> "This is the hot question right now," he said. "We still have to
> demonstrate
> that this phenomenon is possible."
>
> In the meantime, another hot question had remained without a definitive
> answer -
> the etiology of the strange illness that afflicted the people of Carancas.
> But
> the group may solve that mystery, too.
>
> Schultz, Harris and Tancredi all dismissed the possibility of the
> meteorite
> emitting harmful gases that would sicken villagers. Instead, they proposed
> a
> simpler cause: the power of the mind.
>
> The meteorite impact sent out a powerful compression wave that knocked
> nearby
> villagers and animals to the ground and injected the soil with air, which
> later
> bubbled up through the crater. Shepherds and cattle may also have breathed
> in
> the thick dust thrown up by the crash and smelled the sulfurous gases
> produced
> as water reacted with iron sulfide in the meteor.
>
> But what the group thinks later spread through the town was not disease,
> but
> panic.
>
> "We think it was probably more of a psychological response," Harris said,
> adding
> that commonplace symptoms like headaches and nausea could easily have been
> caused by the disorienting impact and then mirrored by frightened
> villagers.
>
> Harris also admitted the possibility of the meteorite releasing arsenic
> deposits, which are known to exist in Peru, but said it would be very
> unlikely
> for those gases to have caused the illness.
>
> "In order to really get arsenic poisoning, you'd need high
> concentrations," he
> said. "You'd have to be there inhaling the vapor filled with the stuff
> right
> after the meteorite hit."
>
> Poisonous or not, the Carancas meteorite could have important implications
> for
> public safety. Tancredi said there's no reason an impact like this
> couldn't
> happen in a major city, wiping out a few city blocks. He also pointed out
> that
> today's most advanced meteor detectors aren't nearly powerful enough to
> detect
> an object as small as the Carancas meteorite.
>
> "Near-Earth detectors detect objects that could create a global
> catastrophe,
> something maybe a kilometer across," he said. "We don't have any kind of
> technology that could detect this object before reaching the atmosphere,
> so it
> will not be possible to know when and where one of these objects could
> strike
> again."
>
> But Schultz said the most important lesson to learn from Carancas is that
> the
> foundation of good science is hard empirical evidence, even - and
> especially -
> when it contradicts established principle.
>
> "We tried to understand what the rocks told us rather than looking at the
> theory," he said. "Nature trumps theory, every time."
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Received on Fri 04 Apr 2008 09:33:09 PM PDT