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  • Makes sense. Those impact rates are only estimates and we'd expect to revise those estimates as we get more data.
    Any metaphor will tear if stretched over too much reality.

    Questions about our site? See the FAQ.

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    • A real nuclear deterrent: US, Russia may team up to use weapons against asteroids

      http://investigations.nbcnews.com/_n...id=msnhp&pos=1

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      • Asteroid threat in 2032? Don't panic, but don't brush it off

        A big asteroid sailed past Earth last month, and astronomers haven't yet totally excluded the possibility that it'll hit us when it comes around in 2032. If the past is any guide, we won't have to worry about asteroid 2013 TV135 — but it's a reminder that we'll have to fend off a killer space rock one of these days.

        Ukrainian astronomers discovered 2013 TV135 just 10 days ago, well after the asteroid had its close encounter with Earth on Sept. 16. Actually, it wasn't all that close: The distance was 4.2 million miles (6.7 million kilometers), or about 17 times as far away as the moon. But based on the rough estimates of its orbital path, experts rated its chances of colliding with Earth during a follow-up encounter in 2032 at 1 in 63,000.
        ...
        Nukes or not, asteroid defense is an international issue well worth contemplating: A space rock that's 1,300 feet (400 meters) wide could destroy a region or set off a huge tsunami if there were a direct hit. The asteroid that caused a meteor blast over Russia earlier this year, injuring more than 1,600 people, was a mere 17 meters (54 feet) wide when it hit Earth's atmosphere.
        ...
        ...But for now, the big challenge is to identify and characterize near-Earth objects on a timely basis. The fact that 2013 TV135 was discovered only after last month's close encounter demonstrates how far we have yet to go.
        http://www.nbcnews.com/science/aster...-it-8C11418631

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        • Risk of massive asteroid strike underestimated

          From the BBC

          An international team looked at the last 20 years of data collected from sensors used by the US government and infrasound sensors positioned around the globe.
          ...
          The researchers found that during this time about 60 asteroids up to 20m in size had smashed into the Earth's atmosphere: far more than was previously thought.
          More - http://www.bbc.co.uk/news/science-environment-24839601

          Link to the original article in Nature - http://www.nature.com/news/risk-of-m...imated-1.14114
          Any metaphor will tear if stretched over too much reality.

          Questions about our site? See the FAQ.

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          • ^ And from another related article, these excerpts;

            In fact, the U.S. government got a new sense of urgency after Chelyabinsk, quietly holding a disaster drill earlier this year in Washington that was meant to simulate what would happen if a slightly bigger space rock threatened the East Coast.

            In the early part of the drill, when it looked as if the meteor would hit just outside the nation's capital, experts predicted 78,000 people could die. But when the mock meteor ended up in the ocean, the fake damage featured a 49-foot tsunami and shortages of supplies along the East Coast, according to an after-action report obtained by the AP.

            The exercise and the studies show there's a risk from smaller space rocks that strike before they are even detected — not just from the long-seen-in-advance, dinosaur-killing giant ones like in the movie "Armageddon," said Bill Ailor, a space debris expert at the Aerospace Corporation who helped coordinate the federal drill.

            "The biggest hazard from asteroids right now is the city-busting airbursts, not the civilization-busting impacts from 1-kilometer-diameter objects that has so far been the target of most astronomical surveys," Purdue University astronomer Jay Melosh, who wasn't part of the studies, wrote in an email. "Old-fashioned civil defense, not Bruce Willis and his atom bombs, might be the best insurance against hazards of this kind."
            ...
            NASA also got a wake-up call this week on those bigger space rocks that astronomers thought they had a handle on, discovering two 12-mile-wide space rocks and a 1.2-mile-wide asteroid that had escaped their notice until this month.

            The three objects won't hit Earth, but their discovery raises the question of how they weren't seen until now.

            The last time a 12-mile-wide rock had been discovered was about 30 years ago, and two popped into scientists' view just now, NASA asteroid scientist Donald Yeomans said. He said NASA had thought it had already seen 95 percent of the large space rocks that come near Earth.
            ....
            http://news.msn.com/science-technolo...-may-be-bigger

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            • That time of year again, the nightly Taurid meteor showers;
              Bright lights in sky probably meteors, Weather Service says
              http://www.latimes.com/local/lanow/l...#axzz2jxdazA8y

              Meteor Shower Lights Up Night Sky Across The West
              ...
              So-called Taurid meteor showers, which seem to come from the direction of the constellation Taurus, will reach their peak this year on Nov. 16 through the early morning of Nov. 17. Observers, aided by a full moon, will see 10 to 20 large fireballs every hour.

              The website PlanetSave.com says the 10-to-20 figure is actually fewer than we normally get in this time period, but that it still promises to be “a pretty good show.”
              ...
              http://losangeles.cbslocal.com/2013/...ross-the-west/

              Wiki page on Taurids;
              http://en.wikipedia.org/wiki/Taurids

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              • We Saw It Coming: Dinky Asteroid Hits Earth, Burns Up

                For only the second time in history, an asteroid has hit Earth that was discovered hours before impact. But don’t panic! The asteroid didn’t put a city-sized divot in our planet, it most likely burned up somewhere between Africa and South America over the Atlantic Ocean at midnight EST.
                Top 10 Ways to Stop an Asteroid
                Asteroid 2014 AA, the first asteroid discovery of the year, was spotted by astronomers using the Mt. Lemmon Survey telescope in Arizona. As shrewdly pointed out by Bad Astronomer Phil Plait, the asteroid was the approximate size of a couch — measuring only a couple of meters across. That’s around one-half of a Mini Cooper, whichever takes your fancy. But whatever your preferred size comparison, the outcome was likely the same; the asteroid burned up on atmospheric entry as a meteor.
                This might have provided a nice visual spectacle only a day after New Years, but 2014 AA is notable as being the first pre-impact discovery of an asteroid since 2008.
                ....
                http://news.discovery.com/space/aste...-up-140102.htm

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                • Did a Comet Kill the Woolly Mammoths?
                  ...
                  Originally published in 2007, Kennett’s controversial Younger Dryas Boundary (YDB) hypothesis suggests that a comet collision precipitated the Younger Dryas period of global cooling, which, in turn, contributed to the extinction of many animals and altered human adaptations.

                  The nanodiamond is one type of material that could result from an extraterrestrial collision, and the presence of nanodiamonds along Bull Creek in the Oklahoma Panhandle lends credence to the YDB hypothesis.

                  More recently, another group of earth scientists, including UC Santa Barbara’s Alexander Simms and alumna Hanna Alexander, re-examined the distribution of nanodiamonds in Bull Creek’s sedimentological record to see if they could reproduce the original study’s evidence supporting the YDB hypothesis. Their findings appear in the Proceedings of the National Academy of Sciences.

                  “We were able to replicate some of their results and we did find nanodiamonds right at the Younger Dryas Boundary,” says Simms, an associate professor in the department of Earth science. “However, we also found a second spike of nanodiamonds more recently in the sedimentary record, sometime within the past 3,000 years.”
                  ...
                  http://www.theepochtimes.com/n3/4829...olly-mammoths/

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                  • Rare Sight: Hubble Telescope Sees Asteroid Falling Apart

                    In a cosmic first, NASA's Hubble Space Telescope has photographed the disintegration of an asteroid in deep space.

                    Astronomers have seen comets break apart as they near the sun, but they'd never witnessed anything similar in an asteroid in the main belt between Mars and Jupiter — until now. Hubble images show that the asteroid, known as P/2013 R3, has fragmented into as many as 10 pieces. Scientists created a video of the rare asteroid P/2013 R3' breakup based on the Hubble views to chronicle the space rock's demise.
                    ...
                    http://www.space.com/24967-rare-aste...pe-photos.html

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                    • Dinosaur-Killing Asteroid Triggered Lethal Acid Rain

                      The oceans soured into a deadly sulfuric-acid stew after the huge asteroid impact that wiped out the dinosaurs, a new study suggests.
                      Eighty percent of the planet's species died off at the end of the Cretaceous Period 65.5 million years ago, including most marine life in the upper ocean, as well as swimmers and drifters in lakes and rivers. Scientists blame this mass extinction on the asteroid or comet impact that created the Chicxulub crater in the Gulf of Mexico.
                      A new model of the disaster finds that the impact would have inundated Earth's atmosphere with sulfur trioxide, from sulfate-rich marine rocks called anhydrite vaporized by the blast. Once in the air, the sulfur would have rapidly transformed into sulfuric acid, generating massive amounts of acid rain within a few days of the impact, according to the study, published today (March 9) in the journal Nature Geoscience.

                      The model helps explain why most deep-sea marine life survived the mass extinction while surface dwellers disappeared from the fossil record, the researchers said. The intense acid rainfall only spiked the upper surface of the ocean with sulfuric acid, leaving the deeper waters as a refuge. The model could also account for another extinction mystery: the so-called fern spike, revealed by a massive increase in fossil fern pollen just after the impact. Ferns are one of the few plants that tolerate ground saturated in acidic water, the researchers said.
                      The Chicxulub impact devastated the Earth with more than just acid rain. Other killer effects included tsunamis, a global firestorm and soot from burning plants. [The 10 Best Ways to Destroy Earth]
                      ...
                      cont'd
                      http://www.livescience.com/43960-ast...ification.html

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                      • Asteroids Whack Earth More Often Than Thought

                        EXCERPT:
                        A global network that listens for telltale traces of nuclear weapons tests detected 26 explosions between 2000 and 2013 caused not by nuclear explosions but by asteroids blasting apart in the atmosphere, a video visualization released on Tuesday shows.
                        Only one impact, the 2013 strike over Chelyabinsk, Russia, caused widespread injuries and damages on the ground, but the study is a somber reminder that Earth's lucky days may be numbered.
                        "Most of the impacts are too small and too high up to cause major damage ... but it does show you ... an asteroid large enough to destroy a city is likely to occur about once every century or so," Ed Lu, a former NASA astronaut who now oversees the asteroid-hunting B612 Foundation, told reporters on a conference call.
                        ...
                        http://news.discovery.com/space/aste...ght-140422.htm

                        Another related article;
                        'The only thing preventing a catastrophe from a city-killer size asteroid is blind luck': Nasa astronauts to reveal evidence that large-scale asteroids have hit Earth 10 times more often than previously thought over past decade
                        http://www.dailymail.co.uk/sciencete...y-thought.html

                        And while on subject of impacts;
                        Ancient plants 'frozen in time' by space impacts
                        http://www.bbc.com/news/science-environment-27075508
                        Last edited by G David Bock; 24 Apr 14, 17:03.

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                        • Twice each year, Earth passes thru the debris cloud known as the Taurid Meteor Stream/Comet Encke. Following illustration shows;


                          http://www.enterprisemission.com/ima...id-stream1.gif
                          http://www.enterprisemission.com/oh_my_god.htm

                          A couple of footnotes about the above. The July transit has the TMS coming from the Sun direction and is mostly a daytime event, the November transit, coming from the outer reaches of the Solar System is a night-time event. Prior to the 15 day calendar adjustment a couple of centuries ago, that Nov. transit was actually the last half of October, might put an interesting insight to some of the Halloween "traditions"/concepts.
                          Last edited by G David Bock; 25 Apr 14, 16:54.

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                          • Chelyabinsk Asteroid Hit Another Asteroid First

                            http://www.nbcnews.com/science/space...-first-n113501

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                            • How NASA's Asteroid Mission Will Head Off 'Armageddon'

                              Experts say it’s just a matter of time before a killer asteroid comes hurtling toward us – but NASA is making progress on plans to grab a space rock and test technologies that could someday save the world.
                              The space agency’s Asteroid Retrieval Mission aims to net an asteroid by the mid-2020s so that scientists can run experiments on it.

                              ...
                              http://www.nbcnews.com/science/space...geddon-n136041

                              Comment


                              • Or alternatively, be used to capture asteroids that could then be reprocessed into construction materials without having to lift them out of a gravity well.
                                Any metaphor will tear if stretched over too much reality.

                                Questions about our site? See the FAQ.

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