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Thread: Bolides, Comets, Asteroids, Meteors And Falling Skies

  1. Link to Post #101
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Video simulations show what would happen if asteroids crashed into Earth's oceans

    Shannon Connellan Mashable Australia
    Tue, 04 Dec 2018 04:01 UTC

    © YouTube/NCAR VisLab

    In films like Armageddon, Hollywood has tried (and failed) to take on the question of what would happen if a comet or asteroid plunged into the oceans on Earth, but what has scientific research actually determined it may look like?

    America's National Center for Atmospheric Research (NCAR) has posted a new video illustrating what could happen if an asteroid crashed into one of our oceans, and it's fascinating.

    Based on data collected by Los Alamos National Laboratory scientists Galen R. Gisler and John M. Patchett, referred to as the Deep Water Impact Ensemble Data Set, these simulations show asteroids of various sizes entering the water from different angles. It's the scale and size of the aftermath that's the truly stunning part.

    Quote
    NCAR Science‏ @NCAR_Science

    What would happen if an asteroid crashed into Earth's oceans?

    This.

    Check out the full visualization (https://youtu.be/o1gSByQVJ2s ) based on the Deep Water Impact Ensemble data set. #sciencevizzy #vizzies #asteroid #NSFfunded


    8:28 AM - 29 Nov 2018
    3 replies 25 retweets 39 likes
    In the full video, you can see a comparison between two variables: one shows impact with no airburst (when a 250-meter, or 820-foot, asteroid hits the ocean intact), and one with an airburst (when the same size asteroid breaks up into pieces before it hits). The dataset outlines more asteroid sizes.

    The video simulation also compares different angles at which the asteroid could hit the body of water. A more oblique angle, the data shows, would be more likely to generate a tsunami.

    Here's the visualization in all its mesmerizing glory:

    The video was submitted by the NCAR to the 2018 IEEE VIS SciVis Contest, a particularly niche and prestigious event dedicated to the visualization of deep water asteroid impacts held in Berlin in October. It was awarded third place with an honourable mention.

    There's very little chance of an asteroid striking Earth anytime soon - a roughly 5,000-foot (1.5 km) asteroid is only estimated to crash into the Earth approximately once every 1 million years. Researchers have spotted a roughly 3,600-foot asteroid (1.1 km) in space that could hit Earth in 860 years, but it has a 0.3 percent chance of doing so.

    So, why do this at all? It's all about being prepared.

    According to the data set report by Gisler and Patchett, NASA is keeping a close eye on asteroids potentially dangerous to Earth. Asteroids that could potentially hit Earth would most likely fall in the ocean, the report adds, which could have serious ramifications for populated coastal areas.

    "NASA's Planetary Defense Coordination Office is keenly interested to know the lower size limit of dangerous asteroids, so as to focus resources on finding all larger objects that potentially threaten the earth," reads the data set report.

    "Since most of the planet's surface is water, that is where asteroids will most likely impact," it continues. "This observation has generated a serious debate over the last two decades on just how dangerous impact-induced waves or tsunamis are to populated shorelines."

    Essentially, the more we know about what an asteroid-generated tsunami looks like, the better prepared we can be - even if the chances of this happening anytime soon are very, very small.
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  3. Link to Post #102
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Fireball that exploded over Greenland shook Earth, triggering seismic sensors

    Mindy Weisberger Live Science
    Thu, 13 Dec 2018 05:53 UTC


    © Getty

    When a blazing fireball from space exploded over Earth on July 25, scientists captured the first-ever seismic recordings of a meteor impact on ice in Greenland.

    At approximately 8 p.m. local time on that day, residents of the town of Qaanaaq on Greenland's northwestern coast reported seeing a bright light in the sky and feeling the ground shake as a meteor combusted over the nearby Thule Air Base.

    But the fleeting event was detected by more than just human observers, according to unpublished research presented Dec. 12 here at the annual conference of the American Geophysical Union (AGU).

    Seismographic equipment, which had been installed near Qaanaaq just a few months earlier to monitor how ground shaking affected the ice, also recorded the fiery meteor blast. The Qaanaaq fireball provided scientists with the first evidence of how an icy environment - and, possibly, a distant ice-covered world - could respond to a meteor impact.

    The first sign of the meteor was a brilliant flash in the sky over Greenland; the meteor was at its brightest at an altitude of approximately 27 miles (43 kilometers) above the ground, and it was traveling at nearly 54,000 mph (87,000 km/h), according to the International Meteor Organization (IMO).

    When the meteor exploded over Thule Air Base, the U.S. Air Force's northernmost base, it was like a bomb going off. With a calculated impact energy of 2.1 kilotons of TNT, this blast was the second-most-energetic fireball of the year, Live Science previously reported. A map of the impact site was shared on Twitter on July 31 by Ron Baalke of the Solar System Dynamics group at NASA's Jet Propulsion Laboratory (and a "space explorer," as he describes himself in his Twitter bio).

    Quote


    Rocket Ron🚀‏ @RonBaalke

    A fireball was detected over Greenland on July 25, 2018 by US Government sensors at an altitude of 43.3 km. The energy from the explosion is estimated to be 2.1 kilotons.


    12:10 PM - 31 Jul 2018
    27 replies 414 retweets 429 likes
    Researchers with the Seismometer to Investigate Ice and Ocean Structure (SIIOS) at the University of Arizona had installed an array of seismometers about 43 miles (70 km) north of Qaanaaq. Recordings captured by the seismic sensors were interpreted by two Danish Seismological Network broadband stations in Greenland: TULEG (Station Thule) and NEEM (Station Eemian). The scientists were then able to identify a seismic event that matched the arc of the traveling ground waves and estimate the impact point of the fireball, the researchers reported at AGU.

    They pinpointed the epicenter of the event near Humboldt glacier on the Greenland ice sheet, and seismic equipment picked up tremors from the impact location as far as 218 miles (350 km) away.

    But their findings also have implications that extend beyond Earth. This seismic event was the first-ever recorded analog for impact events on ice-covered worlds - such as frozen Europa, which is a moon orbiting Jupiter, and frigid Enceladus, an icy moon of Saturn - and these findings "will inform impact science across objects throughout the solar system," the researchers said.

    Related:
    Fireball above US base in Greenland puzzles NASA scientist - jokes about 'Russian strike'
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  5. Link to Post #103
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Apocalyptic Sounds In The Sky: No Explanation For "Mysterious Booms And Flashes Of Light" All Across America

    by Tyler Durden
    Sat, 02/09/2019 - 20:30

    Authored by Michael Snyder via The End of The American Dream blog,

    For weeks, Americans all over the country have been rattled by extremely loud booming sounds that seem to have no explanation, and they are often accompanied by “mysterious flashes of light”.



    These strange booms are shaking homes and rattling windows, and some witnesses say that they sound like cannons being fired. And even though the “mystery booms” and accompanying flashes of light have been captured on camera all across the nation, so far the authorities do not have a reasonable explanation for why they are happening. Unfortunately, it does not appear that this strange phenomenon is going to go away any time soon. In fact, the Sun is reporting that the frequency of these “mystery booms” appears “to have gathered pace over the past week”…
    MYSTERY booming sounds have been shaking houses and terrifying residents after “flashes of light” were spotted across America.

    Experts have been left baffled by a spate of seismic booms from Arizona to New York that appear to have gathered pace over the past week.
    Over this last weekend, this mystery started to get much more national attention after an incident in Rhode Island on Saturday was followed by one in New York City on Sunday
    On Saturday, loud bangs were reported in Rhode Island, where Jeremy Braza’s doorbell captured a video and audio of a loud noise over a three minute period.

    “The whole house shook,” he told TurnTo10.com. “It woke my wife up, woke up all my children.”

    The following night an explosion was heard in New York, accompanied by a mysterious flash in the sky.

    “What the heck was that boom or explosion in park slope Brooklyn?”, asked Matt Wasowski on Twitter.
    But of course this is not just an east coast phenomenon. For example, a “loud boom” that was reported in Tennessee on January 31st was heard across three separate counties
    It began on January 31 when residents of three separate counties in Tennessee reported hearing a loud boom around 11:30 a.m. Local chemical plants were contacted but reported nothing anomalous. Authorities in Bradley, McInn, and Polk counties are still investigating what could have caused such a powerful noise.
    And during that same time frame, numerous North Carolina residents called authorities to report “unexplained loud blasts and booms”
    That same day, local news in North Carolina reported that people in Wake and Franklin counties have been calling law enforcement agencies to report unexplained loud blasts and booms that keep them awake at night. Two homeowners even reported that the booms are so powerful that they have briefly lost power as a result of the tremors. So far, the Wake County Sheriff’s Office has been unable to pinpoint the source of the booms.
    A few days later, “strange explosion-like sounds” were being reported by numerous residents in New Orleans
    The mystery surrounding the strange explosion-like sounds heard by residents in the metro area continues to grow. Late Monday night, several were heard in Lakeview, one of which was caught on camera by Eyewitness News.

    A story that began in Mid-City, has taken crews to Harahan, River Ridge and Wagaman. Now we go to Lakeview, where late Monday night, the mysterious ‘booms’ were heard again.
    Are you starting to see a pattern?

    Large booming sounds are being reported all over the nation, and often those large booming sounds are being accompanied by massive flashes of light. But in every case, the authorities have absolutely no idea what is causing this to happen.

    And in case you were wondering if this was just happening in the eastern half of the country, here is a little taste of what has been going on in Tucson, Arizona
    Faye DeHoff wrote, “first it was a major rattle…like a huge truck about to plow into my home…then the boom..that shook my windows…I was sure some of them were broken but they didn’t…my dog jumped up! I’m at River & Campbell.”

    Ray C. Merrill wrote, “Oracle and Roger, it was shaking pretty good, and long enough for me to watch the blinds dance around, then get up and walk to the doorway, and it was still shaking.”

    There was a similar sensation last week on Thursday, Jan 31 at 8:51 a.m. The same phenomenon; a rumble causing homes to shake and windows to rattle. I felt this one too on the northwest side and once again, so did so many others on Facebook all across Tucson and surrounding areas.
    Some news reports are referring to these strange sounds as “seismic booms”, but there are no corresponding seismic events to back up that claim.

    At this point we have a complete and total mystery on our hands. On YouTube, Jason A has done a great job of compiling news reports about these “mystery booms” from all over America, and you can watch his video right here.

    We have entered a period of time when we should expect the unexpected. Things are strange and they are going to get a whole lot stranger. We aren’t always going to be able to explain what is happening, but without a doubt our planet is becoming increasingly unstable, and that growing instability is going to cause great chaos in the months and years ahead.

    I wish that I knew what was causing all of these “mystery booms”, but I don’t. Thankfully they don’t appear to be causing any serious damage, and hopefully that won’t change.

    Let’s just hope that all of this “shaking” is not leading up to something much bigger, because it isn’t going to take much to push America into a state of utter chaos right now.

    ==========================================

    Sonic booms and bright flashes... and no-one mentions meteors nor bolides...
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  7. Link to Post #104
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Reposted from (here)

    NASA finds possible second impact crater under Greenland ice

    Maria-José Viñas Phys.org
    Tue, 12 Feb 2019 10:26 UTC


    A NASA glaciologist has discovered a possible second impact crater buried under more than a mile of ice in northwest Greenland.m © NASA Goddard

    A NASA glaciologist has discovered a possible second impact crater buried under more than a mile of ice in northwest Greenland.

    This follows the finding, announced in November 2018, of a 19-mile-wide crater beneath Hiawatha Glacier - the first meteorite impact crater ever discovered under Earth's ice sheets. Though the newly found impact sites in northwest Greenland are only 114 miles apart, at present they do not appear to have formed at the same time.

    If the second crater, which has a width of over 22 miles, is ultimately confirmed as the result of a meteorite impact, it will be the 22nd largest impact crater found on Earth.

    "We've surveyed the Earth in many different ways, from land, air and space-it's exciting that discoveries like these are still possible," said Joe MacGregor, a glaciologist with NASA's Goddard Space Flight Center in Greenbelt, Maryland, who participated in both findings.

    Before the discovery of the Hiawatha impact crater, scientists generally assumed that most evidence of past impacts in Greenland and Antarctica would have been wiped away by unrelenting erosion by the overlying ice. Following the finding of that first crater, MacGregor checked topographic maps of the rock beneath Greenland's ice for signs of other craters. Using imagery of the ice surface from the Moderate Resolution Imaging Spectroradiometer instruments aboard NASA's Terra and Aqua satellites, he soon noticed a circular pattern some 114 miles to the southeast of Hiawatha Glacier. The same circular pattern also showed up in ArcticDEM, a high-resolution digital elevation model of the entire Arctic derived from commercial satellite imagery.
    "I began asking myself 'Is this another impact crater? Do the underlying data support that idea?'," MacGregor said.

    "Helping identify one large impact crater beneath the ice was already very exciting, but now it looked like there could be two of them."
    MacGregor reported the discovery of this second possible crater in Geophysical Research Letters on Feb.11.

    To confirm his suspicion about the possible presence of a second impact crater, MacGregor studied the raw radar images that are used to map the topography of the bedrock beneath the ice, including those collected by NASA's Operation IceBridge. What he saw under the ice were several distinctive features of a complex impact crater: a flat, bowl-shaped depression in the bedrock that was surrounded by an elevated rim and centrally located peaks, which form when the crater floor equilibrates post-impact. Though the structure isn't as clearly circular as the Hiawatha crater, MacGregor estimated the second crater's diameter at 22.7 miles. Measurements from Operation IceBridge also revealed a negative gravity anomaly over the area, which is characteristic of impact craters.

    Just 114 miles from the newly-found Hiawatha impact crater under the ice of northwest Greenland, lies a possible second impact crater. The 22-mile wide feature would be the second crater found under an ice sheet, and if confirmed, would be the second crater found under an ice sheet, and if confirmed, would be the 22nd-largest crater on Earth. A NASA-led team discovered the feature using satellite data of the surface of the Greenland Ice Sheet as well as radar measurements from NASA's airborne campaign Operation IceBridge. Credits: NASA's Goddard Space Flight Center/ Jefferson Beck
    "The only other circular structure that might approach this size would be a collapsed volcanic caldera," MacGregor said.

    "But the areas of known volcanic activity in Greenland are several hundred miles away. Also, a volcano should have a clear positive magnetic anomaly, and we don't see that at all."
    Although the newly found impact craters in northwest Greenland are only 114 miles apart, they do not appear to have been formed at the same time. From the same radar data and ice cores that had been collected nearby, MacGregor and his colleagues determined that the ice in the area was at least 79,000 years old. The layers of ice were smooth, suggesting the ice hadn't been strongly disturbed during that time. This meant that either the impact happened more than 79,000 years ago or-if it took place more recently-any impact-disturbed ice had long ago flowed out of the area and been replaced by ice from farther inland.

    The researchers then looked at rates of erosion: they calculated that a crater of that size would have initially been more half a mile deep between its rim and floor, which is an order of magnitude greater than its present depth. Taking into account a range of plausible erosion rates, they calculated that it would have taken anywhere between roughly a hundred thousand years and a hundred million years for the ice to erode the crater to its current shape-the faster the erosion rate, the younger the crater would be within the plausible range, and vice versa.
    "The ice layers above this second crater are unambiguously older than those above Hiawatha, and the second crater is about twice as eroded," MacGregor said.

    "If the two did form at the same time, then likely thicker ice above the second crater would have equilibrated with the crater much faster than for Hiawatha."
    To calculate the statistical likelihood that the two craters were created by unrelated impact events, MacGregor's team used recently published estimates that leverage lunar impact rates to better understand Earth's harder-to-detect impact record. By employing computer models that can track the production of large craters on Earth, they found that the abundance of said craters that should naturally form close to one another, without the need for a twin impact, was consistent with Earth's cratering record.
    "This does not rule out the possibility that the two new Greenland craters were made in a single event, such as the impact of a well separated binary asteroid, but we cannot make a case for it either," said William Bottke, a planetary scientist with the Southwest Research Institute in Boulder, Colorado, and co-author of both MacGregor's paper and the new lunar impact record study.
    Indeed, two pairs of unrelated but geographically close craters have already been found in Ukraine and Canada, but the ages of the craters in the pairs are different from one another.
    "The existence of a third pair of unrelated craters is modestly surprising but we don't consider it unlikely," MacGregor said.

    "On the whole, the evidence we've assembled indicates that this new structure is very likely an impact crater, but presently it looks unlikely to be a twin with Hiawatha."
    More information: Joseph A. MacGregor et al. A Possible Second Large Subglacial Impact Crater in Northwest Greenland, Geophysical Research Letters (2019). DOI: 10.1029/2018GL078126

    Journal reference: Geophysical Research Letters

    Provided by: NASA's Goddard Space Flight Center


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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Two previously unknown massive impact craters discovered

    Andrew Masterson Cosmos Magazine
    Tue, 05 Mar 2019 18:59 UTC

    Hiding in plain sight: Morgan Cox (right) collecting breccia samples at the Yallalie impact site. © A. CAVOSIE

    Researchers have discovered two previously unknown massive craters on Earth, the most recent estimated to have been produced by an impact only 800,000 years ago.

    The craters - one in Western Australia and the other in Nicaragua - are revealed in a pair of papers published in the journal Meteoritics and Planetary Science.

    In one sense, the Australian crater, in a location known as Yallalie, about 200 kilometres north of the state capital, Perth, has long been hiding in plain sight.

    Buried deep beneath the surface, it was first tentatively identified as an impact site in 1992, after its discovery two years earlier during oil drilling exploration.

    Subsequent studies of the 12-kilometre-wide circular formation, which also features a raised central structure three kilometres wide, identified it as the result of several meteorite impacts.

    Now, however, a team headed by Morgan Cox from the Space Science and Technology Centre at Australia's Curtin University has definitively identified the Yallalie crater as the result of single collision.

    The researchers analysed a type of composite rock called breccia, which is created as the result of immense heat and pressure.

    "Breccia formed by impact is a funny-looking rock, kind of like Christmas fruit cake, and that's exactly what the rocks at this site look like," Cox says.

    Previous studies suggested the breccia had formed as a result of meteorite strikes in the near vicinity. It was classified thus as "secondary ejecta".

    Cox and her colleagues looked closely at quartz grains found in the conglomerate, and found evidence that they had been "shocked", strongly indicating that the breccia was the primary result of a single, huge impact.
    "As soon as we identified the telltale microscopic evidence of impact in quartz from the breccia we had evidence of 'shocked minerals' and knew this was the real deal," says Cox.
    In their paper, the researchers present geophysical evidence that constrains the date of the impact to between 89 and 83 million years ago.

    The second crater, however, is much more recent. Its identification also involves researchers from Curtin University.

    A team led by Pierre Rochette from Aix-Marseille University in France was the first to study a circular structure in the jungle of Nicaragua, known locally as Pantasma.

    Initially the researchers were unable to identify the formation, which has a 14-kilometre diameter, as an impact crater, because they were unable to find evidence of shocked minerals.

    A small sample sent to Curtain geochemist Aaron Cavosie, however, provided a key finding.
    "I received a sample of black impact glass, about the size of a marble and I had my doubts," Cavosie recalls.

    "However, when I examined the glass, it contained shocked zircon, with features [found] only in structures formed by impact. It was amazing to find solid evidence of a meteorite impact in such a tiny sample."
    His colleague, Fred Jourdan, also examined the sample. By using argon-dating he was able to determine that the crater was the result of a single meteorite impact that occurred roughly 800,000 years ago.
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    Default Re: "...Climate Change..." (AKA "Global Warming")... is it a scam?

    New Younger Dryas Cosmic Impact Paper - reviewed in detail! UnchartedX Podcast #2
    UnchartedX
    Published on Mar 28, 2019
    "I review the recently released peer-reviewed scientific paper that investigates the Younger Dryas cosmic impact effect in South America.
    This is UnchartedX Podcast #2 - set to imagery and video here on youtube, or you can find the mp3 on my website.

    *please note that I had to alter some of the music in the video after the fact. I had thought that the intro/exit song was CC by, I was mistaken. Apologies for the abrupt audio transitions, but I didn't want the claim to affect the video, as the music is purely background, I don't think it has anything to do with the content of the video itself.

    Link to paper: https://www.nature.com/articles/s41598-018-38089-y
    My marked up copy of the paper is here: http://www.unchartedx.com/2019/03/28/...

    Full transcript is also available on my website."






    Edit: PDF of the highlighted version of the paper: http://www.unchartedx.com/site/wp-co...-marked-up.pdf
    Last edited by Hervé; 16th May 2019 at 19:21.
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    ...

    The skies did fall on our ancestors' heads...
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Oldest meteorite collection on Earth found in the Atacama Desert

    The Geological Society of America, Inc.
    Thu, 23 May 2019 19:22 UTC

    Meteorite recovery campaign in the Atacama Desert (Nov. 2017).© Photo by Katherine Joy (University of Manchester)

    Boulder, Colo., USA: Earth is bombarded every year by rocky debris, but the rate of incoming meteorites can change over time. Finding enough meteorites scattered on the planet's surface can be challenging, especially if you are interested in reconstructing how frequently they land. Now, researchers have uncovered a wealth of well-preserved meteorites that allowed them to reconstruct the rate of falling meteorites over the past two million years.

    "Our purpose in this work was to see how the meteorite flux to Earth changed over large timescales-millions of years, consistent with astronomical phenomena," says Alexis Drouard, Aix-Marseille Université, lead author of the new paper in Geology.

    To recover a meteorite record for millions of years, the researchers headed to the Atacama Desert. Drouard says they needed a study site that would preserve a wide range of terrestrial ages where the meteorites could persist over long time scales.


    Meteorite with thin, dark, fusion crust in the Atacama Desert. © Photo by Jérôme Gattacceca (CEREGE)

    While Antarctica and hot deserts both host a large percentage of meteorites on Earth (about 64% and 30%, respectively), Drouard says, "Meteorites found in hot deserts or Antarctica are rarely older than half a million years." He adds that meteorites naturally disappear because of weathering processes (e.g., erosion by wind), but because these locations themselves are young, the meteorites found on the surface are also young.

    "The Atacama Desert in Chile, is very old ([over] 10 million years)," says Drouard. "It also hosts the densest collection of meteorites in the world."


    The L6 ordinary chondrite El Médano 128, a 556 g meteorite recovered in the Atacama Desert. © Photo courtesy CCJ-CNRS, P. Groscaux.

    The team collected 388 meteorites and focused on 54 stony samples from the El Médano area in the Atacama Desert. Using cosmogenic age dating, they found that the mean age was 710,000 years old. In addition, 30% of the samples were older than one million years, and two samples were older than two million. All 54 meteorites were ordinary chondrites, or stony meteorites that contain grainy minerals, but spanned three different types.

    "We were expecting more 'young' meteorites than 'old' ones (as the old ones are lost to weathering)," says Drouard. "But it turned out that the age distribution is perfectly explained by a constant accumulation of meteorites for millions years." The authors note that this is the oldest meteorite collection on Earth's surface.


    Large meteorite found in the Atacama Desert. © Photo by Jérôme Gattacceca (CEREGE)

    Drouard says this terrestrial crop of meteorites in the Atacama can foster more research on studying meteorite fluxes over large time scales. "We found that the meteorite flux seems to have remained constant over this [two-million-year] period in numbers (222 meteorites larger than 10 g per squared kilometer per million year), but not in composition," he says. Drouard adds that the team plans to expand their work, measuring more samples and narrowing in on how much time the meteorites spent in space. "This will tell us about the journey of these meteorites from their parent body to Earth's surface."


    FEATURED ARTICLE
    The meteorite flux of the past 2 m.y. recorded in the Atacama Desert

    Alexis Drouard; J. Gattacceca; A. Hutzler; P. Rochette; R. Braucher; D. Bourlès; ASTER Team; M. Gounelle; A. Morbidelli; V. Debaille; M. Van Ginneken; M. Valenzuela; Y. Quesnel; R. Martinez. CONTACT: alexis.drouard@lam.fr.

    Paper URL: https://pubs.geoscienceworld.org/gsa...-y-recorded-in.
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Lascaux Shaft Scene and cometary impacts

    Dr. Martin Sweatman Prehistory Decoded
    Sat, 17 Aug 2019 19:12 UTC

    The Lascaux shaft scene is perhaps the most iconic of all European Palaeolithic cave artworks (see below). It shows a bison and human, apparently both dying and normally interpreted as a hunting scene. But we now know, beyond any reasonable doubt, the animal symbols represent constellations, and the Shaft Scene in particular very likely represents a date using precession of the equinoxes.

    © Copy of the Lascaux Shaft Scene, courtesy of Alistair Coombs

    Using the zodiacal method and our ancient zodiac, the date 'written' in the scene is between 15,300 and 15,000 BC (see Prehistory Decoded). The similarity of this scene to Pillar 43 at Gobekli Tepe suggests it documents another asteroid or comet strike, this time from the direction of Capricornus (represented by the aurochs). It so happens that the Taurid meteor stream would have radiated from this direction at this time, suggesting this artwork memorialises another strike from the Taurid system. Given the presence of a giant comet in the inner solar system at this time, such frequent impacts are entirely expected.

    Very interestingly, this time span also corresponds to a sudden temperature fluctuation in the North Atlantic region (see Prehistory Decoded), documented by a Greenland ice core, and to a major cultural transition: the Magdalenian to Azillian.

    The Magdalenian culture occupied Spain and France for around 6,000 years, until around 15,000 BC (note, this time-span equals one entire cycle of apsidal precession of the Taurid meteor stream). It is generally accepted to be divided into three sub-phases; Lower, Middle and Upper. The archaeological record documents these cultural transitions; there are changes in populations and cultural artefacts, indicating significant migrations. However, the transition from Magdalenian to Azillian is an even more pronounced transition (hence the change in name), and the focus of many studies.

    The best radiocarbon data available has been used to model these transitions. The figure below shows the main result. It is the LUM - EAZ transition that concerns us - this is the End of the Upper Magdalenian, and therefore the beginning of the Early Azillian. Converting the calibrated radiocarbon date corresponding to the Shaft Scene to an uncalibrated radiocarbon date (used in this plot), we get 14,050 BP, to within around 150 years. The agreement is perfect - 14,050 BP corresponds exactly to the major Magdalenian - Azillian transition shown here.


    Uncalibrated radiocarbon chronology for multiple Magdalenian sub-phases and the Magdalenian - Azillian transition in Spain and France. © Barshay-Szmidt et al., Quaternary International (2016)
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    ...

    Then there was all that water that came down with the falling skies:

    Did Earth Steal Martian Water?

    Pierre Lescaudron Sott.net
    Sat, 14 Sep 2019 18:31 UTC


    While finalizing the writing of the article titled "Of Flash Frozen Mammoths and Cosmic Catastrophes", I encountered an unexpected anomaly.

    The time of the demise of the mammoths is also known as the Younger Dryas, a period of global cooling that lasted from 12,900 to 11,700 years ago (10,900 B.C. to 9,700 B.C.) during which surface temperatures dropped by approximately 7°.

    In theory, such a severe cooling should increase the volume of polar ice and, as a result, reduce the sea level. However, during the Younger Dryas, the sea levels rose 17 meters over more than a millennium, as illustrated by the graph below.



    Sea level VS global temperature (20000BP-Now)

    If the sea level rose while ice caps were building up, it's possible that the source of the water was external. But where could this water have come from?

    Coincidentally or not, most of Mars' Northern hemisphere was once covered with water, and this ocean has mysteriously disappeared. So where did the Martian water go?

    Sea Levels on Earth
    The Younger Dryas was triggered by major meteorite impacts (c. 12900 BP) on the Laurentian ice sheet as described in the frozen mammoth article. These impacts very likely melted massive quantities of ice and led to a sea level rise. However the 1,200 years of cold temperatures that followed should have frozen at least some water and reduced sea levels, yet sea levels rose dramatically throughout those 1,200 years.

    In any case, the meteorite impacts on the Laurentian ice sheet can only explain a small part of the 17 meter rise observed during the Younger Dryas.
    "Reconstruction of the glacial melt history finds major northward melt-water discharge 13,100-12,500 years ago, at the beginning of the Younger Dryas. The outflow entered the Arctic Ocean, via the Mackenzie River, Fram Strait, and ultimately reached the eastern North Atlantic.'

    Geomorphological data, on the other hand, suggest that still blocked routes to the north and east toward the St. Lawrence Seaway until the end of the Younger Dryas. Sea level curves from Tahiti, New Guinea, and Barbados show a small step (under 6 meters) around 13,000 years ago near the Younger Dryas onset, which may have come from this deluge."

    ~ Vivien Gornitz, Rising Seas: Past, Present, Future, p.127
    According to Leverman et al., a 7°C drop in temperature should lead to a sea level drop of about 28 meters (~4 m/°C). As shown in the diagram above however, the sea level rose about 17 meters during the Younger Dryas, while the melting of the Laurentian ice sheet should have increased the sea level by 6 meters.

    It means that about 39 meters of extra water (17+28-6) was added on the surface of the Earth. Keep in mind that those three figures are just approximations, estimates based on a number hypothesis. They provide us nonetheless with an order of magnitude.

    Water on Mars?



    Giovanni Domenico Cassini (1625-1712)

    In 1666, famous astronomer Cassini, through simple telescope observations, observed ice-like polar caps and clouds on Mars and concluded that there was obviously water on Mars.

    Cassini's view prevailed for a few centuries, but modern science rejected Cassini's claim and the new doctrine became that there was no water whatsoever on Mars. It's only recently, with the massive flow of data coming from Martian probes and rovers, that the evidence became overwhelming that Mars did indeed have water at some point in the past.

    According to a paper published in Science in 2015, Mars used to hold enough water to cover its entire surface in a liquid layer about 140 meters deep. About 85% of this water has, however, "disappeared" (the remaining 15% is stored under ice at the poles).

    Apparently, Martian water was not uniformly spread over the surface of the planet. According to a recent topographic study, most of the Martian water was stored on the North of the planet, in one single ocean, with a similar volume to Earth's arctic ocean.

    If this water was somehow transferred to Earth, it would result in an approximate sea level rise of 34 meters. This figure is comparable, in terms of magnitude, to the 39 meters estimate mentioned above.


    Topographic map of Mars with it ocean

    How Could Mars Lose its Water?
    As noted, most water on Mars has "disappeared". Modern science offers two explanations for this: underground leakage and space leakage.

    Underground leakage is highly unlikely because Mars has no known tectonic plates and therefore no subduction, which is the main phenomenon through which surface water is brought underground.


    Mars crater ditribution

    Space leakage is the second hypothesis which posits that 4.2 billion years ago, Mars lost its magnetic field and, devoid of this protection, solar winds would have stripped the planet of its atmosphere and most of its water within a few hundred million years.

    However, this is probably not true for one simple reason, the top half of the Martian Northern hemisphere (where was once the Martian ocean stood) exhibits far less and far smaller craters than the rest of the planet.

    In 2011, Robbins et al. published a database listing close to 400,000 craters. The picture on the right is excerpted from this paper and shows the geographic distribution of Martian craters (diameters between 30 and 50 km). Obviously, most of Mars' Northern hemisphere exhibits a far lower concentration of craters than the rest of the planet.

    If Mars' ocean disappeared about 4 billion years ago, how can we explain that Mars ocean bed is almost devoid of asteroid impact evidence while the rest of the planet is covered with craters?

    One potential explanation would be that most impacts on Mars happened more than 4 billions years ago, when the ocean was still there and acted as a damper, preventing the formation of craters on Mars surface.


    Geographic concentration of recent craters on Mars

    However, this explanation doesn't seem to hold up. Despite an almost non-existent atmosphere, violent dust storms occur on Mars that erode craters. Given that Robbins et al., identified "well preserved" craters on Mars, these craters must be relatively recent.

    The geographic distribution of this type of crater reveals the same pattern: there are less recent craters where the Martian ocean was in comparison to the rest of the planet.

    The above strongly suggests that Mars lost its water much more recently than mainstream science claims.

    Interplanetary Electric Discharge
    The electric Universe theory, as described in our book Earth Changes and the Human Cosmic Connection, shows how celestial bodies (planets, starts, moons, comets,...) are electrically charged. In addition, such bodies are surrounded by a sort of "insulation bubble" (Double Layer).

    When two astronomical bodies, like two planets, get close enough, an electric discharge forms from the most negative planet to the most positive one, in order to re-balance the electric charge of the two planets. Electric discharges between celestial bodies have been observed several times. Here are a few examples:

    - fragment G of Comet Shoemaker-Levy and Jupiter:
    The Hubble Space Telescope detected a flare-up of fragment "G" of Shoemaker-Levy long before impact at a distance of 2.3 million miles from Jupiter. For the electrical theorists this flash would occur as the fragment crossed Jupiter's plasma sheath, or magnetosphere boundary.

    Thunderbolts, Deep Impact and Shoemaker-Levy 9

    Electric discharge between Jupiter and comet Shoemaker-Levy

    - Io, one of the moons of Jupiter and Jupiter:
    In November 1979, the noted astrophysicist Thomas Gold proposed that the gigantic plumes on Io are not volcanic but evidence of electrical discharging.Years later, a paper by Peratt and Alex Dessler followed up Gold's suggestion, showing that the discharges took the form of a 'plasma gun effect,' which produces a parabolic plume profile, filamentation of the matter within the plume, and the termination of the plume onto a thin annular ring.

    W. Thornhill, The Electric Universe, p.112

    Io exhibiting a massive electrical discharge

    - Herbig Haro object 34. Here, electric discharges, in the form of interstellar Birkeland currents, occur between proto stars and proto planets :


    Electric discharge along HH34 celestial objects

    Electric discharges between celestial bodies are very similar to arc welding. When the negatively charged electrode is brought close enough to the positively charged part, an electric arc, ionized air (plasma), appears and electrons travel in the plasma (along what is called "Birkeland currents") from the electrode (stick) to the welded part in order to re-balance the electric charges.

    Notice that during arc welding, electrons are not the only material transferred from the electrode to the welded part, (negatively charged) molten metal from the tip of the electrode is carried towards the positively charged welded part.

    Another typical feature of such electric discharges is "electric scarring". These fractal patterns are known as 'Lichtenberg figures'. Lichtenberg is the physicist that discovered this phenomenon in 1777. Notice that the polarity of the scarred material has marked influence on the form of the Lichtenberg figure:
    [...] there is also a marked difference in the form of the figure, according to the polarity of the electrical charge that was applied to the plate. If the charge areas were positive, a widely extending patch is seen on the plate, consisting of a dense nucleus, from which branches radiate in all directions.

    Negatively
    charged areas are considerably smaller and have a sharp circular or fan-like boundary entirely devoid of branches. Heinrich Rudolf Hertz employed Lichtenberg dust figures in his seminal work proving Maxwell's electromagnetic wave theories
    [...]

    Article continues below...
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    [...]

    Continued from above...


    Relative Polarity of Mars and Earth
    As described in chapter 8 of Earth Changes and the Human Cosmic Connection, in the Solar system, the Sun is the most positive body. Therefore, the further away from the Sun a planet is, the more negative its electric potential is. Being further away from the Sun than Earth, Mars' electric potential is lower than that of Earth.


    Sun, Earth, heliopshere: relative electric charges

    As a consequence, if an electric discharge happened between Mars and Earth, it started from the most negatively charged body (Mars) and spread towards the most positively charged body (Earth).

    Mars was the cathode (negatively charged) and was stripped from material (gazes, rocks, water) and the electric scarring should exhibit craters, striking at a high point, forming craters and steep side trenches
    If the surface is a cathode (negatively charged), the arc will tend to move across the surface. After striking, usually at a high point, and eroding a crater, the arc may jump to a new high point — the rim of the new crater is a most likely target.

    The abundance of small craters centered on the rims of larger ones testifies to this predictable behavior. As the arc travels, it may erode a series of craters in a line, appearing as a chain of craters.

    If the craters in these chains overlap, the effect is a steep-sided trench with scalloped edges. The arc may erode a trench for a distance and then jump some distance away before eroding another trench. These "dashed line" trenches will usually have circular ends and constant widths. All of these patterns occur in great abundance on the surface of Mars.

    W.Thornhill, The Electric Universe: Part II Discharges and Scars
    Signs of electric discharge on Mars


    Topographic map of Valles Marineris

    If a massive electric discharge occurred between Mars and Earth, is there any trace of a major (negative) Lichtenberg figure as described above to be found on Mars?

    One of the main geological features of Mars is Valles Marineris. At more than 4,000 km (2,500 mi) long, 200 km (120 mi) wide and up to 7 km (4.5 mi) deep, it is the second largest canyon in the entire Solar system, and stretches for nearly a quarter of the planet's circumference.

    Mainstream science theorizes that Valles Marineris formed as a result of water erosion billions of years ago. However, this explanation doesn't seem to match some of the characteristics of Valles Marineris:


    Probe photograph of Valles Marineris
    - In Valles Marineris, the "outflow" is as narrow as the "inflow" and the middle of the course constitutes the broadest part. Overall the width is quite constant, which is unlike rivers that tend to broaden over their course.

    - The "course" of Valles Marineris doesn't follow the downslope. It sometimes "runs" uphill although there is no sign of the damage, rifts for example, that might be expected if the topographical changes were due to later vertical movement of the terrain.

    - Valles Marineris doesn't reveal signs of tribuary "rivers". The two major "rivers" that can be imagined run parallel to each other. The secondary "river" joins the main one at a near right angle, unlike the converging path usually exhibited by tributaries that join a main river

    - The floor of Valles Marineris reveals transverse markings, unlike river beds that tend to have longitudinal markings shaped by the river flow.

    - The "tributaries" exhibit a V-shaped cross-section while water erosion typically forms U-shaped river beds.

    - Valles Marineris banks are very deep (7 km) and very steep. The banks show no sign of water erosion and its typical horizontal marking. On the contrary, the markings reveal a vertical chevron pattern.

    Bank of Valles Marineris

    While the features of Valles Marineris seem to contradict the water erosion theory, they are very consistent with the distinctive features of (negative) electric scarring:
    When planets come close, gargantuan interplanetary lightning results. It is perfectly capable of stripping rock and gases from a planet against the puny force of gravity. It does so leaving characteristic scars. [...]

    The parallelism of the canyons is due to the long-range magnetic attraction of current filaments and their short-range strong electrostatic repulsion.

    Particularly significant are the small parallel rilles composed essentially of chains of craters. A traveling underground explosion follows the lightning streamer and cleanly forms the V-shaped tributary canyons.

    There is no collapse debris associated with undercutting water flow.Similarly, the "V" cross-section is usual for craters formed by underground nuclear explosions. The circular ends of the tributaries, where the explosion began, are precisely of that shape.

    In comparison, headward erosion by ground water sapping gives a U-shaped cross-section and does not necessarily end in a circular alcove.

    Note that some of the tributary canyons on the south rim of Valles Marineris cut across one another at near right angles. This might be due to repeated discharges from the same area chasing the main stroke as it travelled along Ius Chasma. No form of water erosion can produce crosscutting channels like that.

    The fluted appearance of the main canyon walls is probably due to the same travelling explosive action.

    W. Thornhill, Mars and the Grand Canyon
    Interestingly, Valles Marineris is contiguous to the ocean that once covered most of Mars' ocean. If Vallles Marineris was the place of an electric discharge between Mars and Earth, the adjacent Martian ocean would have certainly been affected, and possibly transferred.

    Evidence of Material Transfer From Mars to Earth

    As mentioned in the above quote, a massive electric discharge from Mars to Earth could have stripped significant quantities of rocks from Valles Marineris. So, before looking for signs of a major (positive) electric discharge on Earth, let's see if there is any evidence of Martian rocks on Earth.

    As of 2019, 237 Martian meteorites have been found on Earth according to the Meteoritical Society. So, transfer of material from Mars has occurred.

    One might assume that this phenomenon is very ancient and occurred billions of years ago when planets were forming, asteroids were rampant and orbits were unstable. But data suggests that this is not exactly the case.

    While the landing time for most of Martian meteorites is unknown, a few have been dated, in particular the Martian meteorite commonly abbreviated ALH84001 that was found in 1984. Its ETA on Earth has been estimated at 13,000 years ago (11,000 B.C.).

    According to Hamilton et al., the origin of ALH84001 is Valles Marineris because of its geological nature (orthopyroxenite), which is the only place where orthopyroxenite has been found (spectral analysis). In fact, ALH84001 is the only orthopyroxenite Martian meteorites. No other meteorite of this kind has been found on Earth.


    Martian meteorite ALH84001

    Interestingly, because of its carbonates content, ALH84001 is the only meteorite originating from a time period during which Mars is suspected to have supported liquid water. ALH84001 is an abbreviation which stands for ALlan Hills 84001. Allan Hills is located along the Southern coast of Antarctica.

    Now, let's recapitulate some key characteristics of ALH84001:
    - It comes from Valles Marineris
    - At the time of its arrival on earth, Mars was a wet planet
    - It landed on Earth 13,000 years ago
    - It was found in Antarctica
    It would be interesting to know if some Martian meteorites come from its oceanic bedrock. Unfortunately, the geological composition of the oceanic bedrock of Mars is unknown because it is covered with a thick layer of sediment. However the mineralogical composition of the coast of Mars' dry ocean is known and directly related to some Martian meteorites found on Earth.

    Indeed, there is a rare type of Martian meteorite called "nakhlite". Only 21 specimens have been found on Earth so far. Nakhlites are rich in augite (a silicium based mineral) and they formed from basaltic magma about 1.3 billion years ago.


    Theorized geographical origin of nakhlites

    Because of the composition and age of the nakhlites, they are believed to originate from one of these three Martian volcanic areas: Tharsis, Elysium, or Syrtis Major Planum.

    Interestingly, as shown of the map on the right, each of those three volcanic constructs is situated near the coast of what was once the Martian ocean.

    Of the 21 nakhlite meteorites that reached Earth, 7 of them were found in Antartica, That is 33%. This is a high percentage knowing that only about 12% of all meteorites that reached Earth were found in Antartica. Mass wise, 16.9 kg of nakhlite meteorites were found in Antarctica, that is 54% of the total mass of nakhlite meteorites.

    Lastly, the nakhlite meteorites are believed to have fallen to Earth up to 10,000 years ago. This figure is quite close to the arrival date of ALH84001 (13,000 years ago).

    Any Sign of Electric Discharge on Earth?
    If a massive electric discharge initiated from Valles Marineris and hit Earth, where did the hit occur?

    There are several canyons on Earth, including the Great Canyon, that hold features of electric scarring. However, the data about Martian meteors provided in the previous chapter, reveals a strong affinity of Martian meteorites for Antarctica.


    Spectroradiometry of Princess Elizabeth land

    Does the bed rock of Antarctica show any sign of positive electric scarring, i.e. a massive canyon-like geological feature? Indeed it does. As shown in the satellite picture above, Antarctica is considered to host the largest canyon on Earth, according to a 2016 geological survey:
    [...] the largest unsurveyed region on the icy continent is a region called Princess Elizabeth Land. Now a team of geologists has scoured that area to reveal a massive subglacial lake and a series of canyons, one of which — more than twice as long as the Grand Canyon — could rank as Earth's largest.
    At this point, Martian meteorites and traces of electric scarring point to Antartica for a potential location for the Mars-Earth transfer. But what about the main constituent of the whole process, water?

    If Mars lost most of its water to Earth, there should be some evidence of this massive transfer, on our planet in general and in antarctica in particular.

    Could part of the Antarctica ice sheet be of Martian origin? To answer this question, let's first observe the Antarctican ice-sheet and then compare it to its Arctic counterpart.


    Topographic map of Antarctica

    The Antartica ice sheet is massive. It contains about 30 million km3 (7.2 million cubic miles) of ice. This represents more than 70% of Earth's freshwater. In comparison, the artic ice sheet, located over Greenland, is only 2.9 million km3, (0.68 million cublic miles).

    In terms of volume, the Northern ice sheet is less than 10% of Antarctica ice sheet. Notice also that Antartica does not form one single solid continent. It's more like an archipelago constituted of a few massive islands separated by deep marine areas as depicted in the map above.

    Between the islands covered by the antarctic ice-sheet, the bedrock can be as low as 2500 meters below sea level. This means that in some places the ice sheet is more than 4 km (2.7mi) thick: 1.5 km (1mi) above sea level and 2.5 km (1.7mi) below sea level (see cross section of Antarctica below)


    Antarctic cross section

    For comparison, the arctic sea ice reaches a maximum thickness of 4 meters with ridges up to 20 meters, although the average depth of the Arctic ocean is 1038 meters, which is comparable to the depth of the Antarctic "ocean".

    The question then arises: why is there so much more ice in Antartica compared to the arctic? Why does Antartica ice extend 2,500 meters below sea level and reach the bedrock while Arctic ice is a mere 4 meter thick layer floating on the ocean?

    [...]

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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    [...]

    Continued from above...


    According to mainstream science the antarctic and Greenland ice sheet were formed because of the incremental accumulation of snow, year after year. This suggests that Antarctica experienced a lot more snowfall. But, data shows the opposite. Indeed, Antarctica is one of the driest place on Earth with only 18 cm/year of percipitation, while the Arctic region experiences almost double this figure with 32 cm/year.

    If Antartica receives less snow than the Arctic region, the only explanation for its tenfold higher quantity of ice is that it experiences less melting. Maybe Antarctica is experiencing much colder temperatures relative to the Arctic region? Again the data suggests the opposite.

    As shown in the graph below, for eons the Arctic region has been much colder than Antartica. For the last 11,000 years, the Antarctic has been marginally colder than the Arctic.



    Artic VS Antarctica temperatures

    Also, notice in this same graph the close correlation between Greenland (GISP2) and Vostok (Antarctica) ice core-based temperature reconstruction from today back to the Younger Dryas. What we see is that, around 11,000 years BP, a sudden and marked de-correlation occurred. Between 11,000 BP and now, the two temperature curves are very similar in shape and very close in terms of value. Before this time (50kY BP to 11 kY BP) the two curves are totally divergent.

    Are these two curves a testimony to the environmental conditions of two different planets?

    In any case, no endogenous cause (snowfall difference, temperature difference) can explain the marked difference in depth and volume between the antarctic ice sheet and the arctic one. A massive and sudden inflow of exogenous water (in ice form) in Antarctica would explain these discrepencies.

    How Could Mars Get so Close to Earth?
    Mars exhibits the second largest eccentricity of all planets in the Solar system. Large eccentricities usually suggest orbits that were disrupted in the recent past. Because of this marked eccentricity, Mars can get as close as 56 million kilometers from Earth, as shown in the diagram below.


    Mars and Earth orbits

    For comparison Earth's magnetotail extends more than 6 million km (blue and purple ellipse in the image above).

    So, electrically speaking, Mars is only one order of magnitude away from of Earth. However, the normal distance between Earth and Mars is too large for any electric discharge between the two planets. But could some kind of cosmic disruption have brought the two planets abnormally close?

    The obvious agent for such a massive orbital disruption would be comet, but one large enough to move Mars, which is ten times heavier than the Moon, away from its initial orbit.

    This scenario is actually the main theory developed by Emanuel Velikovsky in his best-selling book: "World in collision" published in 1950.


    Immanuel Velikovsky (1895-1979)

    Using mostly comparative mythology, Velikovsky proposed that Venus was initially a comet and disrupted the orbit of Mars, that subsequently made a close approach to Earth.

    Scientific leaders ruthlessly lambasted Velikovsky's catastrophist theory, because it directly threatened their fundamental paradigm, uniformitarianism, without which the church of materialist progress and its darwinian atheist creed would inevitably collapse. Adding insult to injury, Velikovsky based his work on religious texts and showed that they might carry more truth than expected.

    Velikovsky realized that if his scenario was true, several predictions could be made about the astronomical bodies involved. After all, the merit of a theory is based on its predictive abilities. The predictions Velikovsky made were in total contradiction with the prevailing views of the time.

    Decade after decade, space programs provided extra data that made it possible to test Velikovsky's claims. Unexpectedly, most of them turned up to be true.Some of the most noticeable predictions were the Jupiter radio signal, the Sun net electric charge and Earth's magnetosphere extending behind the moon.

    Analyzing all the true predictions made by Velikosvky is beyond the scope of this article, however.

    Since we have already gathered information about a potential encounter between Mars and Earth, we will now focus on the last piece of puzzle: Is Venus a comet? And, in particular Velikovsky's predictions relative to the cometary nature of Venus.

    The nature of Venus was the pivotal point of the controversy surrounding Worlds in Collision. If Venus was not a comet, the whole chain of events was impossible. Conversely, if Venus was indeed a comet, Velikovsky's Earth-Mars close encounter scenario becomes much more plausible.

    Was Venus a Comet?
    According to mainstream science, Venus is a sister planet of Earth and Mars. They formed the same way (accretion), from the same material, in the same region, over the same time span.Contrary to this model that prevailed at the time, Velikovsky's predictions about Venus and its cometary nature were as follows:
    - Venus is a hot planet because until recently it was a comet.

    Planet Venus © NASA

    In the 1950's, the scientific consensus was that Venus was an old planet similar to Earth and Mars, and given that its orbit is similar to Earth and Mars, its temperature should be similar too. At the time, Venus' temperature was "known" to be -25°C (-13°F) and some scientists even believed that Venus might be habitable.

    But when space probe Mariner 2 sent back its data in 1963, the scientific community was flabbergasted. Venus' average surface temperature was a whopping 462°C (864°F). The "habitable" planet had the temperature of molten lead!

    The hot nature of Venus was confirmed in 1991, when Kiefer et al. measured gravitational variations over Venus, from which they deduced that Venus crust was very thin (10-20 km) compared to the crust of "sister" planets like Earth or Mars (50-100 km).

    This thin lithosphere indicates that Venus has a hot, active interior that prevents the crust from cooling down and hardening over a substantial thickness..

    In conclusion, as predicted by Velikovsky, Venus is indeed a hot planet, on the surface as well as inside. This strongly suggests that not long ago Venus was still a blazing hot comet and that it has not yet fully cooled down from its previous cometary state.
    - Venus is a young planet because until recently it was a comet.
    In 1950's, the prevailing theory was that Venus was an old planet that formed through accretion billions of years ago. As a consequence, because of its exposure to asteroids for billions of years, it was believed to be crater-laden.

    But these were only assumptions because, at the time, the surface of Venus could not be directly observed due to its very dense atmosphere. In the 1970's, the first Venusian probes allowed direct observations of Venus surface and revealed that Venus had a surprisingly low number of craters.

    These repeated observations strongly suggest that, as predicted by Velikovsky, Venus is a young planet. Until recently it was still a comet, therefore not enough time in its "planet life" has elapsed for it to be impacted a large number of times.


    The relatively pristine surface of Venus © NASA/JPL
    - Venus should have an anomalous rotation
    According to Velikovsky, because of its recent cometary nature and its chaotic interaction with Mars and Earth, Venus should display a anomalous rotation compared to other planets in the Solar system.

    This prediction was, like the others, considered as heresy. But in 1962, the US Naval Research Laboratory in Washington announced that Venus had a slow retrograde rotation. It is the only planet in the Solar system to display a retrograde rotation.


    Resonance pattern of Venus relative to Earth © Imgur

    Confirming Venus' peculiar celestial movements, Goldreich et al. demonstrated in a paper published in 1966 that Venus' spin was in resonance with Earth's orbit - each time Venus passes between the Sun and Earth, it shows the same side to Earth.

    Such a resonance strongly suggests a relatively recent close approach between Earth and Venus, which "locked" the spin of the smaller planet with the orbit of the larger one. In addition, one of the main arguments that sought to refute Velikovsky's theory was that Keplerian orbits can not cross each other - so that collisions or near-collisions can't occur.

    In a paper titled "Velikovsky and the sequence of planetary orbit", L.E. Rose et al demonstrated that not only can Keplerian orbits cross each other, but Venus could have had a highly elliptical (cometary) orbit in the recent past, that the Solar system could have exhibited stable planetary orbits before the arrival of Venus, and that Venus could have acquired a circular orbit soon after its integration to the Solar system.

    Venus electrical activity
    Because of Venus' cometary nature and its past interactions with Mars, Velikovsky predicted that Venus should display some electrical activity. In the 1950's, this prediction was contrary to the scientific consensus which considered Venus as an electrically inert planet. This view prevailed for decades. But in 2006, the electric activity of Venus was proven when the 'Venus Express' satellite observed lightning in the Venusian atmosphere.

    This was just the beginning of the revelations about Venus' electric nature. In a paper published in Nature in 2007, Pätzold et al. showed that Venus was also surrounded by an extensive ionosphere (the positively charged layer of the atmosphere).

    A few years later, in 2013, the ESA announced that Venus did not have a normal spherical ionopshere but a teardrop-shaped ionosphere, i.e. a comet tail, as illustrated by the image below.


    Venus tear-shaped ionosphere © ESA

    Venus' comet tail is very long: 45 million km (29 million miles), so long in fact that its ion tail reaches Earth when the Sun, Venus and Earth are aligned.


    Venus ion tail

    Notice that Venus, originally a comet that finally settled along a stable orbit in the Solar system, is not an isolated case. In chapter 21 of our book "Earth Changes and the Human Cosmic Connection" we described in detail how several planets of our Solar system have acquired a number of new moons that were previously cometary bodies.


    Number of moon (1975 VS. 2013)

    [...]

    Article continues below...
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    [...]

    Continued from above...


    When Did The Water Transfer Occur?
    We started this article with an "anomaly": during the Younger Dryas, a period of dramatic cooling, the sea level rose markedly instead of dropping (because of the increasing volume of ice). Since the hypothesis is that a massive dump of Martian ice can explain this anomaly, the close encounter with Mars should have happened soon after the beginning of the YD, which is dated to 12,900 B.P.

    But are there other pieces of evidence that confirm this sequence of events and clarify the time that elapsed between the beginning of the YD (cometary bombardments) and the Mars encounter (ice and water dump)? As we will see below, several sources of information - among them ancient maps, reconstruction of past sea level and past temperatures and moraine analysis - can give us a pretty clear idea of when the water transfer from Mars to Earth likely occured.

    Ancient Maps
    Several maps dating back to the rennaisance show an ice-free Antarctica. Here we will focus on the Piri Reis map (dated to 1513), the Oronteus Finaeus map (1532) and the Buache map (1737).

    The authenticity of these maps has been thoroughly tested. The book "Maps of the Ancient Sea Kings" by Charles Hapgood demonstrates that not only are the maps genuine, but also that the people who drew them had an excellent knowledge of longitudes, latitudes and spherical trigonometry, a branch of geometry that reached its complete form only at the end of the 19th Century. It is clear also that the original designers of these maps had explored and surveyed the whole world and knew the exact size circumference of our planet.


    The Buache map (1737)

    While these maps date back to the 16th Century, Antartica was only discovered three centuries later in 1820. This suggests that these three maps are medieval copies of ancient original maps drawn at a time when Antarctica was indeed an ice-free continent. Also notice the Buache map (above) shows an ice-free Antractica made of two main islands.

    20th Century radar mapping of the Antartican rockbed has confirmed that Antarctica is not one solid single island, but rather an archipelago comprising two main islands.

    A close examination of the Orontius Finaues map (below) reveals a number of river inlets and islands along the coast of Antarctica. These features are now under water. This suggests that at the time when the original Oronteus Finaues map was drawn, the sea level was noticeably lower than it is today.


    The Oronteus Finaeus map and an ice-free Antarctica

    In some cases, the features are now more than 120 meters under water. As shown in the image below, the only time over the last 125,000 years when water level was that low was about 15,000 years ago.


    Sea level over the past 140 kY

    Were these maps drawn 15,000 years ago, when the water level was low enough for the now submerged land features to be exposed? If these ancients maps representing an ice-free Antarctica were drawn about 15,000 years ago, then the close encounter with Mars and the accompanying ice dump must have happened later.

    Sediment analysis from Antarctica confirms that the original maps have to date to at least 6,000 years ago since the analysis of sediment cores of the Ross Sea reveal fine river sediments, i.e. non frozen/active rivers connecting to the Ross sea at that time.

    So we have a date range for the Mars encounter somewhere between 6,000 and 15,000 years ago. Can we narrow this range?

    Sea Level And Temperatures

    The sea level drop (about 30 meters) that should have been induced by the YD cooling (12,900 to 11,700 years ago) didn't happen, and we can hypothetise that it was offset by the intake of Martian water. To know more precisely when this intake might have occured however, we need to take a closer look at coral-based sea level analysis. The sea level graph found at the beginning of this article displays a very smooth curve because it is the average sea levels based on the analysis of the several coral reefs.

    If we examine this coral reef data individually, it appears that it shows some variability. As shown by the chart below, each reef has its own history:


    Sea level from coral reefs data

    In the graph above, the Barbados coral records (blue line following the diamond symbols) show a steep increase (blue arrow) followed by a sudden trough (green arrow) quickly followed by a second steep increase (yellow arrow). There are only about 500 years between the two steep increases.

    The reconstructed temperature history (based on the analysis of oxygen18 isotope) during the Younger Dryas reveals a very similar picture:


    Temperatures during the Younger Dryas

    The graph above shows that the beginning of the Younger Dryas is marked first by a drastic cooling (blue arrow) followed, about four centuries later, by a second abrupt cooling (green arrow). Do the two consecutive spikes in temperature drops and sea level rise suggest two consecutive major cooling events? Like the cometary bombardment described in our previous article (c. 12900 BP) and, a few centuries later, the Mars-Earth interaction (c.12500 BP) described in this article?

    Moraine Analysis

    The quick succession of two major cooling events at the beginning of the YD seems to be confirmed by moraine analysis as described by Anthony Watts in the following excerpt (moraines are geological formations that mark the limit of the ice extent):
    The Younger Dryas was not just a single climatic event. Late Pleistocene climatic warming and cooling not only occurred before and after the YD, but also within it. All three major Pleistocene ice sheets, the Scandinavian, Laurentide, and Cordilleran, experienced double moraine-building episodes, as did a large number of alpine glaciers. Multiple YD moraines of the Scandinavian Ice Sheet have long been documented and a vast literature exists. The Scandinavian Ice Sheet readvanced during the YD and built two extensive end moraines across southern Finland, the central Swedish moraines, and the Ra moraines of southwestern Norway(Fig. 4). 14C dates indicate they were separated by about 500 years.

    Anthony Watts, The intriguing problem of the Younger Dryas

    Double Younger Dryas moraines of the Scandinavian Ice Sheet.

    Beyond the case of the Scandinavian ice sheet, Loch Lomond in Scotland provides very similar evidence:
    Among the first multiple YD moraines to be recognized were the Loch Lomond moraines of the Scottish Highlands.[...]. The Loch Lomond moraines consist of multiple moraines. Radiocarbon dates constrain the age of the Loch Lomond moraines between 12.9k and 11.5k calendar years ago
    Ancient maps, temperature and sea level reconstruction and moraines analysis all provide a consistant picture. The beginning of the YD seems to have been marked by two distinct catastrophic cooling events that happened in close succession:
    1/ c.12,900 BP - A major cometary bombardment as described in the previously mentioned article and generally accepted by modern science

    2/ c.12,500 BP - A few centuries later, a close encounter between Earth and Mars and the accompanying water/ice dump (not generally accepted by mainstream science).
    Conclusion
    The information gathered above enables us to hypothesize a scenario for the second event (c.12,500 BP) that involves the following steps:
    1/ Venus, a cometary body, enters the Solar system and follows a typical eccentric cometary orbit around the Sun and Jupiter

    2/ Comet Venus passes by Mars and disrupts its orbit

    3/ Mars' disrupted orbit brings it very close to Earth

    4/ The close proximity between Mars and Earth triggers a massive electric discharge transferring Martian material, including most of its ocean, to Earth.
    The very little time that elapsed between the two events (about 4 centuries which is a blink of an eyes on the celestial time scale), makes us wonder if they are not somehow related. Maybe the comet Venus was part of a cometary swarm of which it constituted the main object. After entering the Solar system, the Venus cometary swarm followed a typical Jupiter-Sun orbit with a period of about 52 years (this is the orbit duration for comet Venus as suggested by Velikovsky).

    This eccentric orbit passed close to the Earth orbit and during the first crossing, some of the bodies included in the swarm were attracted by Earth gravity and provoked a substantial cometary bombardment with no less than 5 major meteorites with diameters in excess of 10 km reaching Earth. This could be the catastrophic event (c.12,900 B.P.) that initiated the Younger Dryas.

    Because of its higher momentum, Venus then pursued its orbit around the Sun and Jupiter. After 7-10 revolutions (350-500 years), Venus came very close to Mars, knocked it out of its orbit and pushed it dangerously close to Earth, leading to the electric discharge described above.

    This scenario is close to the one proposed by Veliskovsky 70 years ago. The only substantial differences are the water transfer and, of course, the dating. In fact, the dating was the main argument brought against Velikovsky (c. 3500-2800 B.P.). It is still the main bone of contention today, as illustrated by this excerpt of the Wikipedia article about Velikovsky's book:
    So far, the only piece of the geologic evidence which has shown to have a catastrophic origin is a "raised beach" containing coral-bearing conglomerates found at an elevation of 1,200 feet above sea level within the Hawaiian Islands.

    The sediments, which were misidentified as a "raise beach", are now attributed to megatsunamis generated by massive landslides created by the periodic collapse of the sides of the islands. In addition, these conglomerates, as many of the items cited as evidence for his ideas in Earth in Upheaval, are far too old to be used as valid evidence supporting the hypothesis presented in Worlds in Collision.

    Deluge accounts (blue column) in world mythologies © Eddinger

    The more recent dating suggested by Velikovsky isn't backed up by much evidence in the form of major catastrophes affecting the whole planet (although there is a good case for a catastrophe localized in the Middle Age that marked the end of the Bronze Age).

    On the other hand, the onset of the Younger Dryas (c.12,900-12,500 BP) offers plenty of evidence of sudden and major changes over the entire planet.

    Velikovsky considered that the second event, a close encounter between Mars and Earth and its accompanying water/ice dump, was referenced in mythology as the great flood. He based his dating mostly on the chronology offered by the Old Testament (c.2800 BP). But the Hebrew mythology as recorded in the Old Testament is only one of numerous mythologies mentioning the Great Flood. In 500 cultures spanning all continents, researcher Douglas Eddinger found that about 90% of them included an account of a great deluge. The prevalence of this myth in most cultures all across the planet suggests that the Deluge was truly a worldwide catastrophe.

    The Old Testament is not the oldest account of the Great Flood. It is predated by the ancient Mesopotamian Gilgamesh epic (Utanapishtim's tale, tablet XI), which is about 5,000 years old.

    According to University of Chicago professor A. Heidel, author of The Gilgamesh Epic and the Old Testament Parallels, Mesopotamian and Hebrew myths could descend from an even older common original. In any case, the written version of the Epic was preceded by oral versions. Beyond the age of written history, traces of accounts of the catastrophic events that set the Younger Dryas can be still found, even in the oldest archeological neolithic site.

    Gobelki Tepe is an archeological site located in Southern Turkey. Its deepest layer dates back to c. 10,000 BP. Its major archeological feature is the vulture stone, a massive carved pillar also known as pillar 43 (image below).


    The Vulture Stone

    According to University of Edinburgh lead researcher Martin Sweatman, the vulture stone is a astronomic representation where, like today, animals represent constellations and the whole scene displays a cosmic catastrophe. Computer model analysis carried out to match the patterns of the stars detailed on the Vulture Stone points to one specific date: 12.950 BP, which is exactly the date of the onset of the Younger Dryas.


    Nicolas Poussin, The Universal Deluge

    Pierre Lescaudron
    Pierre Lescaudron (M.Sc., MBA) pursued a career in executive management, consulting and post-graduate teaching in high tech fields.
    He then became an editor and writer for SOTT.net, fulfilling his dream of researching science, technology and history.
    ==============================================

    The above article should give one a pretty good idea of what these Red and Blue Kachinas were all about...

    ---

    Related: 'Behaving like a comet': Astronomers discover enormous exoplanet with wild, slingshot-like orbit
    Last edited by Hervé; 14th September 2019 at 19:25.
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    New evidence sheds light on Younger Dryas impact hypothesis

    Francis Thackeray The Conversation
    Wed, 02 Oct 2019 21:58 UTC


    © Shutterstock

    Just less than 13,000 years ago, the climate cooled for a short while in many parts of the world, especially in the northern hemisphere. We know this because of what has been found in ice cores drilled in Greenland, as well as from oceans around the world.

    Grains of pollen from various plants can also tell us about this cooler period, which people who study climate prehistory call the Younger Dryas and which interrupted a warming trend after the last Ice Age. The term gets its name from a wildflower, Dryas octopetala. It can tolerate cold conditions and was common in parts of Europe 12,800 years ago. At about this time a number of animals became extinct. These included mammoths in Europe, large bison in North America, and giant sloths in South America.

    The cause of this cooling event has been debated a great deal. One possibility, for instance, is that it relates to changes in oceanic circulation systems. In 2007 Richard Firestone and other American scientists presented a new hypothesis: that the cause was a cosmic impact like an asteroid or comet. The impact could have injected a lot of dust into the air, which might have reduced the amount of sunlight getting through the earth's atmosphere. This might have affected plant growth and animals in the food chain.

    Research we have just had published sheds new light on this Younger Dryas Impact Hypothesis. We focus on what platinum can tell us about it.

    How platinum fits into the picture
    Platinum is known to be concentrated in meteorites, so when a lot of it is found in one place at one time, it could be a sign of a cosmic impact. Platinum spikes have been discovered in an ice core in Greenland as well as in areas as far apart as Europe, Western Asia, North America and even Patagonia in South America. These spikes all date to the same period of time.

    Until now, there has been no such evidence from Africa. But working with two colleagues, Professor Louis Scott (University of the Free State) and Philip Pieterse (University of Johannesburg), I believe there is evidence from South Africa's Limpopo province that partly supports the controversial Younger Dryas Impact Hypothesis.

    The new information has been obtained from Wonderkrater, an archaeological site with peat deposits at a spring situated outside a small town to the north of Pretoria. In a sample of peat we have identified a platinum spike that could at least potentially be related to dust associated with a meteorite impact somewhere on earth 12,800 years ago.

    The platinum spike at Wonderkrater is in marked contrast to almost constantly low (near-zero) concentrations of this element in adjacent levels. Subsequent to that platinum spike, pollen grains indicate a drop in temperature. These discoveries are entirely consistent with the Younger Dryas Impact Hypothesis.

    Platinum spike and temperature graph. © Francis Thackeray

    Wonderkrater is the first site in Africa where a Younger Dryas platinum spike has been detected, supplementing evidence from southern Chile, in addition to platinum spikes at 28 sites in the northern hemisphere.

    We are now asking a question which needs to be taken seriously: surely platinum-rich dust associated with the impact of a very large meteorite may have contributed to some extent to major climatic change and extinctions?

    A meteorite crater in Greenland
    Very recently a large meteorite crater with a diameter of 31km was discovered in northern Greenland, beneath the ice of the Hiawatha glacier. It is not certain that it dates to the time of the Younger Dryas, but the crater rim is fresh, and ice older than 12,800 years is missing.

    It seems possible (but is not yet certain) that this particular crater relates to the hypothesised meteorite that struck the earth at the time of the Younger Dryas, with global consequences.

    The effects of a meteorite impact may potentially have contributed to extinctions in many regions of the world. There is no doubt that platinum spikes in North America coincide closely with the extinction of animals on a big scale about 12,800 years ago.

    Extinctions in Africa
    In a South African context, my team is suggesting that platinum-rich cosmic dust and its associated environmental effects may have contributed to the extinction of large animals that ate grass. These have been documented at places such as Boomplaas near the Cango Caves in South Africa's southern Cape, where important excavations have been undertaken.

    At least three species went extinct in the African subcontinent. These included a giant buffalo (Syncerus antiquus), a large zebra (Equus capensis) and a large wildebeest (Megalotragus priscus). Each weighed about 500kg more than its modern counterpart.

    There may have been more than one cause of these extinctions. Hunting by humans could have been a factor. And the large buffalo, zebra and wildebeest had already been affected by habitat changes at the end of the last Ice Age, which was at its coldest about 18,000 years ago.

    What about human populations? A cosmic impact could have indirectly affected people as a result of local changes in environment and the availability of food resources, associated with sudden climate change. Stone tools relate to the cultural identity of people who lived in the past. Around 12,800 years ago in at least some parts of South Africa there is evidence of an apparently abrupt termination of the "Robberg" technology represented by stone tools found for example at Boomplaas Cave.

    Coincidentally, North American archaeological sites indicate the sudden end of a stone tool technology called Clovis.

    But it is too early to say whether these cultural changes relate to a common causal factor.

    Map showing platinum spikes. © Francis Thackeray

    Reality check
    The Younger Dryas Impact Hypothesis, and the evidence to support it, is a reminder of how much can change when a rocky object hits the earth. Many asteroids are situated between Mars and Jupiter, and on occasion some come very close to our planet. The probability of a large one striking earth may seem to be low. But it's not impossible.

    Take Apophis 99942. It is classified as a potentially hazardous asteroid. It is 340 metres wide and will come exceptionally close to the earth (in relation to an Astronomical Unit, the distance between us and the sun) on Friday April 13 2029. The probability of its hitting us in ten years' time is only one in 100,000. But the probability of an impact may be even higher at some time in the remote future.

    What's more, comets associated with the Taurid Complex approach the earth relatively closely at intervals of centuries. So a large asteroid or comet could fall to earth in the foreseeable future.

    The Younger Dryas Impact Hypothesis is highly controversial. But the evidence suggests it is not improbable that a large meteorite struck the earth as recently as 12,800 years ago, with widespread consequences.
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    Default Re: Bolides, Comets, Asteroids, Meteors And Falling Skies

    Ancient Assyrian tablets seem to reference a massive solar storm

    Ryan F. Mandelbaum Gizmodo Australia
    Thu, 17 Oct 2019 04:27 UTC

    The aurora in Alberta, Canada. © Keith E. Doucet, Wikimedia Commons

    Scientists report that they may have found the earliest written record of a solar storm in ancient Assyrian tablets.

    Recent analyses have found evidence of an extreme solar storm that left energetic particles in tree rings and ice cores across the world sometime around 660 BCE.

    With this in mind, a research team in Japan and the United Kingdom wondered if they'd be able to find evidence of this storm in ancient astrological records — and they may have found something in Assyrian tablets.

    Back in the 19th century, archaeologists uncovered thousands of tablets dating back to the Assyrian empire in Mesopotamia, which documented treaties, stories, including the now-famous epic of Gilgamesh, and astrological reports. These reports included observations of the planets, phenomena like comets and meteorites, and of course, predictions of omens.

    The researchers (today's researchers) scanned through a collection of these astrological reports in search of auroral-type events, which they define as "reddish luminous phenomena in the sky" and are caused by the Sun's particles interacting with the atmosphere. Many of the reports weren't dated, but the researchers could at least produce date ranges based on the astrologer who wrote the report.

    They found three reports that seemed to mention auroral phenomena: one reporting a "red glow," another a "red cloud," and a third reporting that "red cover[ed] the sky," according to the paper published in The Astrophysical Journal Letters.

    The records correlate with date ranges of 679 BCE to 655 BCE, 677 BCE to 666 BCE, and 679 BCE to 670 BCE, respectively. Assyria might seem too far south to view the aurora, being at approximately the same latitude as North Carolina, but past research shows that the North magnetic pole was much closer to the Middle East in the 7th century BCE (and especially strong solar storms can cause the aurora to move south).

    These records seem to correspond to tree ring data and ice core data showing quick increases in radioactive elements associated with solar activity during this time. Obviously they're just correlations — but perhaps these tablets are the earliest-yet records of intense auroral activity.

    The ice core and tree ring data suggest that the 660 BCE storm would have been quite powerful. A blast of particles following a solar flare could have even punched a hole in the ozone layer. It's one of the strongest candidate solar proton events on record, alongside similar-looking events from 775 CE and a weaker event around 993 CE.

    Scientists hope to better understand and eventually be able to predict these storms, since they'd wreak havoc on our electrical infrastructure. And if you're an ancient Assyrian, surely a red cloud would be a bad, bad omen.
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