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Space Science

ESA Plans Test of Asteroid Defense System 305

vinlud writes "It has been announced by Dutch television ESA has chosen the Don Quijote programme to investigate the possibilities of altering the collision course of asteroids heading for Earth. The program, selected among five other studies, contains two spacecraft: Hidalgo and Sancho. Hidalgo will impact an asteroid of approximately 500 m diameter at a relative speed of at least 10 km/s while Sancho will retreat to a safe distance to observe the impact. An animation of the mission sequence (6.49 Mb) can be downloaded from here."
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ESA Plans Test of Asteroid Defense System

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  • by superpulpsicle ( 533373 ) on Saturday July 10, 2004 @03:57PM (#9662387)
    What's important is a very efficient backup of slashdot so I can still post in the case of a continent size meteor hitting earth.

  • Bull's eye! (Score:5, Insightful)

    by zeux ( 129034 ) * on Saturday July 10, 2004 @03:57PM (#9662389)
    I RTFA (however, I'm not new here!) and it seems all the other five studies were about observation only missions. This one is the only one to propose an actual 'impact'.

    It's definitively more exciting but I wonder if it's not too hard to make such a millions miles away 'bull's eye'. 500 m in diameter is pretty small at this distance...
    • Re:Bull's eye! (Score:5, Interesting)

      by Rob Carr ( 780861 ) on Saturday July 10, 2004 @04:23PM (#9662538) Homepage Journal
      It's definitively more exciting but I wonder if it's not too hard to make such a millions miles away 'bull's eye'. 500 m in diameter is pretty small at this distance...

      With the ability to correct the flight enroute, it shouldn't be too difficult at all. When Cassini went into orbit around Saturn, the navigation was so precise that they did not need to do a corrective burn.

      Still, if for some gosh-awful reason you can't hit a 500 m target, this is the perfect time to find out!

      Here's a bunch of folks that will probably have fun looking to see what effect the collision might have: The folks on the Minor Planet Mailing List [bitnik.com] are really into tracking the orbits of these rocks. I wouldn't be surprised if their data is the stuff that narrows the error bars on this experiment!

    • I did NOT RTFA re: asteroid defense systems. So I am left puzzling over just what asteroids need to be defended from?
    • Re:Bull's eye! (Score:3, Insightful)

      by arivanov ( 12034 )
      Not very hard. After all there will be multipple course corrections over the length of the mission. So it is likely to be as hard as it was for the Hidalgo to hit one of the Wind Mills. With similar results.

      All I can say is hats down and apploads to the cynicist who thought of the name for this program. It is a near perfect description of our current technological ability to change the orbit of a NEO.
      • Re:Bull's eye! (Score:3, Insightful)

        by Tim C ( 15259 )
        It is a near perfect description of our current technological ability to change the orbit of a NEO.

        You know what they say - practice makes perfect.
      • Not only does it accurately represent the potential effectiveness of this particular program, but also the necessity for an asteroid defense program in general. But I suspect the technology could be useful someday, likely for something other than the defense of the Earth from asteroids.
    • I think the ESA had managed to make a probe orbit an asteroid, and even managed a soft landing or near-landing as well with the same probe. Granted, it was a larger asteroid, but I think that is about as difficult as hitting a 500m target, with the benefit of carefully calculated course corrections.
    • by Anonymous Coward
      onder if it's not too hard to make such a millions miles away 'bull's eye'. 500 m in diameter is pretty small at this distance.

      It's not impossible. I used to bullseye womprats with my T-16 back home. They're not much bigger than 500 meters.
  • Low expectations? (Score:5, Insightful)

    by October_30th ( 531777 ) on Saturday July 10, 2004 @03:59PM (#9662399) Homepage Journal
    Do they have low expectations or why is the project named after a fictional character [wikipedia.org] who was rather bonkers and fought windmills?

    "The full original title was El ingenioso hidalgo don Quixote de la Mancha. The adjective "quixotic," meaning "idealistic and impractical," derives from his name, and the expression "tilting at windmills" comes from his story."

    • by joeykiller ( 119489 ) on Saturday July 10, 2004 @04:04PM (#9662430) Journal
      Well, Don Quijote believed he were fighting knights, while he actually was fighting windmillds.

      Most people would say that it would be impossible if not futile to attack windmills and believe you could win over them. But Don Quijote never doubted his abilites, no matter what Sancho Panza thought.

      Maybe this is what ESA has thought about when they named their mission: Keep hope up, no matter how impossible the task seems.
    • I had the same thought. Do we really want Earth's defenses named after a character who hallucenated that windmills were evil giants?

      On the other hand, IIRC, one of the themes of the book was many people tended to humor Don Q. and --in the humoring-- they joined him in his fantasy world. Maybe the name is an attempt to get buy-in on the project?

      I have to admit that Sancho is appropriately-named, since throughout the entire book, Sancho held back and observed instead of joining Don Q. in action.

    • by ttsalo ( 126195 )
      Do they have low expectations or why is the project named after a fictional character who was rather bonkers and fought windmills?

      Well, since the impactor weighs nearly nothing compared to an 500m asteroid and is going to have negligible effect, it's named very accurately. The whole point of this thing is that it's easier to scale up from something than to start completely from scratch.

      --

    • I believe the primary goal is to determine the composition of the asteroid, not have any expectations to destroy it. From the article: "We must know in detail the internal structure of asteroids, and how they respond to impacts before we can design effective mitigation methods."

      -cp-

      Alaska Bugs Sweat Gold Nuggets [alaska-freegold.com]

    • Do they have low expectations or why is the project named after a fictional character who was rather bonkers and fought windmills?

      This makes perfect sense to me. now that I've actually read a summary of the story written by a Spaniard, [google.com]

      • The mission has two main players: Hidalgo and Sancho. Hidalgo is the (fictional) title of Don Quixote (the lowest rank of nobility). Sancho is his squire and, at a critical point in the story, the source of the narrative switches to him.
      • Don Quixote tilts at imaginary
    • by barakn ( 641218 )
      What do you suppose tilting is? Aiming or thrusting (a lance) in a joust. Hidalgo will tilt at an asteroid exactly like don Quijote tilted at windmills. They have not low but high expectations that Hidalgo will not survive the experience, much like one would expect someone tilting at a windmill to have an unpleasant experience (imagine having your lance shatter in your hands). The mission is beautifully named.
  • by sdo1 ( 213835 ) on Saturday July 10, 2004 @04:01PM (#9662408) Journal
    Hidalgo will impact an asteroid of approximately 500 m diameter at a relative speed of at least 10 km/s...

    ... altering its trajectory into a orbit scheduled to collide with Earth in 2006 at which point the real test will begin.

    -S

    • ... altering its trajectory into a orbit scheduled to collide with Earth in 2006 at which point the real test will begin.

      You shouldn't have revealed that this is all part of a conspiracy to get their funding pumped up to $1-trillion to solve the problem for real. Don't answer that knocking at the door!
  • by Space cowboy ( 13680 ) * on Saturday July 10, 2004 @04:02PM (#9662413) Journal
    ... yes I know, space is big... [grin]

    Simon
  • Will /. editors never learn?
  • by Anonymous Coward on Saturday July 10, 2004 @04:04PM (#9662427)
    ...is to send Ben Affleck and Bruce Willis to the asteroid. One could make an animation of this, but it might result in a god-awful, 2-hour-long mistake.
  • by Doc Ruby ( 173196 ) on Saturday July 10, 2004 @04:07PM (#9662444) Homepage Journal
    These "asteroid defense" systems are lies told by weapons makers. They are designed to be expensive systems that can be pointed at the Earth. When the "missile defense" lies (eg. that they work) fail, as they always have in Europe, weapons makers turn to another irrational fear: asteroids. The odds of an asteroid damaging Europe are so much lower than many other preventable crises that the entire sham is transparent. The odds of AIDS killing millions is much higher, and more preventable. The odds of climate change killing millions are also much higher. The odds of a generation of people learning to watch TV rather than learning to read or think are much higher. There are known solutions to these likely crises that will cost less, and benefit much more. But they don't play on the kind of irrational fear that lets governments spend billions of people's money without accountability. So we'll pay for these lies once when we fund the sham, and again when the real threats come home to roost.
    • you clearly know nothing of the consequences of fat tails and outliers
      • by Doc Ruby ( 173196 ) on Saturday July 10, 2004 @04:30PM (#9662591) Homepage Journal
        Are you saying that the odds of the Earth suffering nation-scale damage from a meteorite are higher than the odds of crippling illiteracy, plague, drought/flood, or any of a number of other affordably solvable problems? You clearly know nothing but the exotic details of your planetoid fetish. Don't expect the rest of us, more interested in our home planet's fortunes, to be similarly dazzled.
        • last I checked the dino's were more than nationwide, no?
          Illiteracy has not been a problem for what, 5000 years or so?
          If anything, the planet is at its most literate today. As for plagues, they come and go and are have a lot more to do with sanitation. Last check the septic system in N. America and Europe was pretty good. Droughts and floods have been going on since Noahs time, and frankly I think it a lot more likely we manage to deflect/blow up a big rock in space than change the weather in any significant
          • The impact that apparently killed the dinosaurs was over 65 MILLION years ago. When was the prior one? With that kind of frequency, we can afford to eradicate AIDS and cope with the Greenhouse before we're actually threatened by an asteroid. And illiteracy is a problem everywhere. The plague we're talking about, AIDS, isn't affected by sanitation, it's affected by education - literacy - and expensive national health care. When we spend billions of dollars on defense, it's important to separate the size of p
            • Well, lets put it this way. Your odds of dying from an asteroid impact are about the same as the odds of dying in an airline crash. Therefore spending on asteroid defence should be in a similar ballpark to spending on airline safety.

              -
        • How about this dysfunctional moderation:

          Starting Score: 1 point
          Moderation 0
          50% Overrated
          50% Underrated
          Karma-Bonus Modifier +1 (Edit)
          Total Score: 2
    • The odds of an asteroid damaging Europe are so much lower than many other preventable crises that the entire sham is transparent. The odds of AIDS killing millions is much higher, and more preventable. The odds of climate change killing millions are also much higher.

      There's still much to be learned about how likely an impact is. We don't know how many near Earth objects (NEOs) there are. We are especially uncertain about the number of smaller NEOs, because they are hardest to detect.

      The smaller but stil

      • I'll leave aside the distinction without difference between Dutch and British interests in "Europe". Spending money tracking objects in the Solar system is worthwhile, in innovation, science, and exploration. SOme of those benefits will also help develop technology to protect us from the other threats of ignorance, pollution and disease. But spending the vastly larger amounts on systems which fraudulently target a negligible risk, instead of the real threats, is not just bad policy. It's a LIE: supporters'
        • I am not sure about missile efectiveness on a NEO episode, probably very low, but if you look at ancient history (miths and ancient traditions) there are clear traces of similar episodes in our past.

          Fire from sky, falling rocks, tidal waves and other catastrofic events are recorded in almost every tradition all over the world. In fact I don't know of any single ancient culture without this kind of memories.

          As someone said about a NEO impact; the question is not 'if', is just 'when'. Our traditions regis

          • And their traditional response to these events is to prey on the fear of their unsophisticated followers, telling a story to bolster the masses' faith in the leaders, claiming credit for defense and divine favor, while wasting everyone's time with lipflapping. They didn't get antiasteroid defense, and neither will we. We've got the time-honored tradition of lying about intimidating, but nonthreatening, heavenly events for money and power. Of course the official stories never forget these essential events of
            • Agreed on historic manipulation by religions and politics, but the lets not forget that the fact is that this kind of memories exist on every tradition, from the 'big' ones to the small aboriginal peoples.

              That excludes the posibility of being only local plots, and the simplest remaining explanation is that these are memories from natural events. The interesting part is that if even in our limited memories (just some thousands of years) we already have that kind of experiences, those episodes seems to be m

              • From aborigines to corporate christians, we're all exploitable by faithmongers. I also infer a history of astronomy encoded in these myths. But the length of the history need not be so short: there's no reason that the recent (5Ky) stories can't be retellings of more ancient (14+Ky) ones. Or even older - recent acceleration of changes indicate that long-past generations were much more conservative of passed "wisdom", possibly extending back several iceages or more, perhaps in the 100+Ky range, or even older
                • astronomy is a clasical and easy explanation, the problem I have with this one, is that 1) is too simple and 2) is an opinion from our own culture, 'we' have astronomy but what about the ones that lived 20Ky before?.

                  There's still no reason to believe that devastating impacts are more frequent than we did before.

                  No, no more frequent, but if our memories are right, they already happened (ie: there are strong indications of an abrupt end of the Bronce Age (3.5Ky), that expanded across northen africa to mid

                  • Everyone has astronomy, in the sense I use the word: names for the "stars" (distant objects in the sky). Ancients seem to have had much more sophisticated astronomy than pre-20th Century Eur/Americans, as detailed in books like Hamlet's Mill and The Orion Mystery, even if you reject the authors' inferences. Their framework was in the form of anthropocentric myth, but the encoded info guided them by starlight around the global seas.

                    Information about predictive frequency requires both a mechanical model and
                    • But that doesn't line the pockets of weapons makers, so we remain in the grip of faith/fear that has ruled us since time immemorial.

                      just to be fair: modern weapon makers are not responsable of inmemorial stupidity, just unlimited greed. :)

            • Blockquoth the poster:

              They didn't get antiasteroid defense, and neither will we.

              Um, they didn't get an antiasteroid defense because, well, they had neither a functioning and comprehensive understanding of celestial mechanics, nor a history of remote sensing, nor a well-developed rocket industry, nor nuclear weapons, nor...

              To say that the ancients were duped and that we are being duped in the same way is just simply silly. No matter what the evil overlords of religion had said 3Kyears ago, they could

              • We're closer to antiasteroid defense than were they, but not nearly close enough to be safe. But that doesn't stop the weapons makers from pretending we can buy that safety from them, just as they've been pretending for decades that they'll protect us from missiles. They'll sell it to us, and we won't be hit (for hundreds, thousands of years), and they'll take the credit for keeping us calm. It was ever thus. Don't let our fancy toys convince you that people are much wiser than our ancestors. If anything, o
                • Blockquoth the poster:

                  Don't let our fancy toys convince you that people are much wiser than our ancestors.

                  We're not a lot wiser, perhaps, but we are much more capable.

                  On the other hand: slavery is now universally illegal. (It's not gone, but it's gone underground, and that's still progress.) Maybe we are wiser after all.
    • In my opinion, AIDS is not a government problem.

      In many ways, AIDS is completely preventible and needs no government money. So many people are fully aware of the risks and yet continue to have unprotected sex and share needles. I don't see the point in spending government money to protect people from themselves.

      IIRC, auto accidents kill more people than AIDS does. I don't see the point in halting space research just because people are still willing to kill each other.
      • You don't understand public health. Large groups of people, who are subject to epidemics, don't behave simply as large numbers of individuals. The group needs administration as a group, or their behavior will be prey to "social diseases" like AIDS. Whether or not you personally get AIDS, the damage to the society in which you live, due to lowered productivity, morale and distraction of healthy caretakers, is worth protecting you from. Do you resent the taxes you pay that maintain ghetto fire departments, or
        • Blockquoth the poster:

          Do you resent the taxes you pay that maintain ghetto fire departments, or schools?

          Are you kidding? This is slashdot, where we're all wide-swinging libertarians. What the heck is the repressive government doing in the ghettos, anyway? Why shouldn't the inhabitants have the right to burn whatever they want? And if conditions are bad, well, they should have chosen better when selecting their parents.

          In case it isn't obvious: {SARCASM} {/SARCASM} tags should be inserted.

    • Isn't it ironic to moderate the parent post as Funny?

      • I get these "Funny" mods from time to time. Maybe it's a "clicko", as mods use the GUI poorly. I also get lots of inappropriate "Troll" and "Flamebait" mods, but I ascribe those to Anonymous moderator Cowards who mod rather than reply. Maybe an AmC who likes the post, but doesn't know why, rates it "Funny" rather than reply with support. That's the kind of mismoderation that could include ignorance that "Funny" doesn't add any points.
    • Here are some odds and probablities [oregonlive.com] as compiled by the oddities who write The Edge for The Oregonian (Portland, OR newspaper). Short version: it is actually more likely that the Earth will be smacked by a large asteroid in your lifetime than you becoming a professional athelete.

      And remember, before you try to beat the odds, make sure you can survive the odds beating you.
  • Damn! (Score:4, Funny)

    by slimyrubber ( 791109 ) on Saturday July 10, 2004 @04:11PM (#9662478)
    Guess we are doomed to die by hunger, terrorism, violent climate shift, war or MPAA.
    I was really betting it would be an asteroid.
  • Unfortunately because of the rotating news system of the NOS (Dutch TV) text pages (and the time before the story was posted) the news item already has disappeared :( . I hope other sites will soon release more information about the plans and time table of the project!
  • by Anonymous Coward on Saturday July 10, 2004 @04:13PM (#9662485)
    Try it out here [squadron13.com].
  • so.... (Score:4, Interesting)

    by bman08 ( 239376 ) on Saturday July 10, 2004 @04:13PM (#9662488)
    is this just a hip way to repackage missile defense testing so that nobody gets mad?
    • There may be a point to it. The problem is the EU has been so staunchly against ABMs that I don't see how the policy makers would let this through if they thought this would be the case.

      I can imagine that if NASA was testing this, there would be an uproar because of such a theory.

      Being able to hit a 500m asteroid in a very well known and predictable orbit is not nearly the same as being able to hit a 5m wide rocket in a potentially unstable and unpredictable trajectory.
    • No, I don't think so, but maybe they repackaged this essentially scientific mission as 'the asteroid destroyer'.
      By arguing that the mission helps to save mankind by deflecting hazardous objects, they'll get funding and support from the general public.

      Since it is disappointing what most people think of space exploration, do not consider this "repackaging" improbable.
  • It's All in the name (Score:5, Informative)

    by Count of Montecristo ( 626894 ) on Saturday July 10, 2004 @04:18PM (#9662517) Homepage
    While there will be incessant puns about the characters that this project is named after; given the fact that in the book, Don Quixote was out of his mind, I feel it is very appropriate, since it describes excactly what it does.

    Perhaps the most famous part of this book is when Don Quixote gallantly charged at windmills, while Sancho watched. In his troubled mind, The windmills were evil Giants, which he sought to destroy to win the favors of his sweethart Dulcinea, wich is a very accurate depiction of what the program is supposed to do.

    I find that the depiction, regardless of the obvious fact that in the book it was a hopeless cause; is a romantic metaphore, rather than an endorsement of failure, poor engineering or idealistic but unreachable goals.

    As a side note, this book (El ingenioso Hidalgo, Don Quixote de la Mancha) is to the Spanish Language as The Count of Montecristo is to French, Luther's New testament translation is to German, and the works of Shakespeare are to English.

    • As a side note, this book (El ingenioso Hidalgo, Don Quixote de la Mancha) is to the Spanish Language as The Count of Montecristo is to French, Luther's New testament translation is to German, and the works of Shakespeare are to English.

      As a Frenchman, I can tell you that while Montecristo is certainly the best book written by Dumas and probably in the fifty most important French books written, it is not "The Book". That honour would probably go to Victor Hugo's "Les Misérables".

      I'm pleased by the
    • As a side note, this book (El ingenioso Hidalgo, Don Quixote de la Mancha) is to the Spanish Language as The Count of Montecristo is to French, Luther's New testament translation is to German, and the works of Shakespeare are to English.

      Not only that, it's the most translated book after the bible [amazon.com]. I just started reading it (in spanish), and I'm enjoying it a lot myself ;)

  • by pyrrhonist ( 701154 ) on Saturday July 10, 2004 @04:29PM (#9662576)
    From the project's web page:
    It has been acknowledged by the scientific community that NEO may represent a hazard to Earth.

    But Neo is The One!

  • Missing the point (Score:5, Insightful)

    by Anonymous Coward on Saturday July 10, 2004 @04:33PM (#9662604)
    I can see that most slashdotters are trolling on the actual mission of the spaceships. Their purpose is to impact the asteroid to determine its composition, structure, ect. to then, determine an appropiate course of action.

    And the names do fit. They fit because Don Quijote tried to bring back the idealized lifestyle of chivalry. His desire was to protect the good cause and perhaps slay a dragon or two in the way. He was mocked by people because they believed such perils were nonexistent. Just like we mock this far fetched perhaps, but still necesary project that aims to be our first line of defense in case of a possible, if not improbable event.

    I fail to see how people can criticize this and yet run SETI at home on their computers.

    Godspeed Don Quijote, and Sancho Pansa, I for once, am gratefull of your so much needed lunacy.
  • Number Crunching (Score:5, Interesting)

    by Rob Carr ( 780861 ) on Saturday July 10, 2004 @04:46PM (#9662658) Homepage Journal

    Assuming that the Hildalgo probe masses in at 25 kg (the same as Sancho - it might be less) and is moving at 10km/sec and assuming the asteroid has a density of 3g/cc (giving a mass of 4x10^10 kg, and if the probe is absorbed into the asteroid and no material is lost from the asteroid, then the change of velocity for the asteroid will be about 6x10^-9 km/sec.

    For comparison, the asteroid probably has a velocity somewhere on the order of 5-10km/sec.

    If the asteroid and probe hit head on with both having a velocity (relative to the sun) of 10km/sec, then you can double the change to 1.2x10^-8 km/sec

    It's probably a good idea to check my work. Here's how I did the calculation:

    Let m1 be the probe and m2 be the asteroid.

    v(center of mass)=(m1*v1+m2*v2)/(m1+m2). v2=0 for this reference frame and m1+m2 essentially equals m2. Since we're in the reference frame of the asteroid being stationary, the combination of probe and asteroid will still have the same velocity for the center of mass.

    I hope I didn't botch this estimate....

  • ...courtesy of Project Gutenberg. [gutenberg.net].
  • objectives (Score:4, Informative)

    by kyknos.org ( 643709 ) on Saturday July 10, 2004 @05:49PM (#9662968) Homepage
    The mission has a very high scientific value, but it will also help in testing technologies required for future deflection missions and raise interest in people for space exploration. The mission will in particular: measure the mass of the asteroid, the ratio of the moments of inertia and the low order harmonics of its gravity field. model the asteroid shape before and after the impact, to detect changes (if any). determine the asteroid internal structure, especially the size the main solid pieces, the average particle size and thickness of regolith and of the debris layers in the space left between the main pieces. constrain the mechanical properties of the asteroid material. measure the orbital deflection of the asteroid as a result of the impact of Hidalgo measure the asteroid rotation state before and immediately after the impact. detect the dissipation of the non-principal axis rotation after the impact. determine the asteroid large scale mineralogical composition.
  • by wrc ( 99060 )
    It's about time our species started putting together and testing serious contingency plans against this sort of catastrophe.

  • Am I the only one whose first thought on seeing the topic was, "If they're testing the asteroid defense, wouldn't that require an asteroid coming toward Earth?"
  • once we discover that the asteroid was indeed a camouflaged research vessel from an alien civilization. This "research project" could plunge Earth into an intergalactic war!
  • What a dumb idea! Disintegrate a potentially deadly asteroid so the earth can be showered by the debris instead. Hope there aren't any big chunks! Since it is likely any large asteroid collision will be detected years in advance a very slight course correction using a chemical rocket would suffice. If bombarding an asteroid with a projectile has scientific merit, great. But don't pretend the activity has any relevance to asteroid hazard avoidance.

    • Re:Dumb idea (Score:3, Informative)

      by juhaz ( 110830 )
      Disintegrate? Where the hell did you get THAT idea from? "Course collection" is what this thing IS doing, it's not Bruce Willis with nuclear bomb.

      You don't have much of a change disintegrating 500m asteroid by hitting it with a probe weighting few hundred kilos unless you're doing the ramming at relativistic speeds.
  • by Ralph Spoilsport ( 673134 ) on Sunday July 11, 2004 @02:34AM (#9664990) Journal
    If that little 500m sucker clobbered LA (my fave target) and you were 100km away out in the desert, the impact calculator [arizona.edu] says:

    Impact Effects Robert Marcus, H. Jay Melosh, and Gareth Collins

    Your Inputs:
    Distance from Impact: 100.00 km = 62.10 miles
    Projectile Diameter: 500.00 m = 1640.00 ft = 0.31 miles
    Projectile Density: 3000 kg/m3
    Impact Velocity: 10.00 km/s = 6.21 miles/s
    Impact Angle: 45 degrees
    Target Density: 3000 kg/m3
    Target Type: Competent Rock or saturated soil

    Major Global Changes:
    The Earth is not strongly disturbed by the impact and remains intact.
    The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
    The impact does not shift the Earth's orbit noticeably.

    Energy: 9.82 x 1018 Joules = 2.35 x 10^3 MegaTons TNT
    The average interval between impacts of this size somewhere on Earth is 4.3 x 10^4 years

    Crater Size:
    Transient Crater Diameter: 4.59 km = 2.85 miles
    Final Crater Diameter: 5.63 km = 3.50 miles
    The crater formed is a complex crater.

    Thermal Radiation: Time for maximum radiation: 0.43 seconds after impact
    Visible fireball radius: 3.5 km = 2.2 miles
    The fireball appears 7.9 times larger than the sun
    Thermal Exposure: 3.60 x 104 Joules/m2
    Duration of Irradiation: 6 seconds
    Radiant flux (relative to the sun): 6.5

    Seismic Effects:

    The major seismic shaking will arrive at approximately 20.0 seconds.
    Richter Scale Magnitude: 6.9
    Mercalli Scale Intensity at a distance of 100 km:
    VI. Felt by all. Many frightened and run outdoors. Persons walk unsteadily. Windows, dishes, glassware broken. Knickknacks, books, etc., off shelves. Pictures off walls. Furniture moved or overturned. Weak plaster and masonry D cracked. Small bells ring (church, school). Trees, bushes shaken (visibly, or heard to rustle).
    VII. Difficult to stand. Noticed by drivers of motor cars. Hanging objects quiver. Furniture broken. Damage to masonry D, including cracks. Weak chimneys broken at roof line. Fall of plaster, loose bricks, stones, tiles, cornices (also unbraced parapets and architectural ornaments). Some cracks in masonry C. Waves on ponds; water turbid with mud. Small slides and caving in along sand or gravel banks. Large bells ring. Concrete irrigation ditches damaged.
    Masonry C. Ordinary workmanship and mortar; no extreme weaknesses like failing to tie in at corners, but neither reinforced nor designed against horizontal forces.
    Masonry D. Weak materials, such as adobe; poor mortar; low standards of workmanship; weak horizontally.

    Ejecta: The ejecta will arrive approximately 144.2 seconds after the impact.
    At your position the ejecta arrives in scattered fragments
    Average Ejecta Thickness: 4.6 mm = 0.1822 inches
    Mean Fragment Diameter: 3.5 cm = 1.37 inches

    Air Blast:

    The air blast will arrive at approximately 333.3 seconds.
    Peak Overpressure: 19232.2 Pa = 0.1923 bars = 2.7310 psi
    Max wind velocity: 38.2 m/s = 85.4 mph
    Sound Intensity: 86 dB (Loud as heavy traffic)

    So let's see - you're 100 km away - first you experience a 6.9 earthquake, and the red hot 4.6mm fragments arrive 144 seconds later? Great - that's like 250 km per hour... Nice. Anyone in the open is DEAD, and your house might not survive that either. Then after being weakened by a major earthquake and a barrage of highspeed rocks, an 86 mph wind comes to visit.

    Great. Sounds pretty crappy to me. I doubt that it would be the end of the world (Except for LA, but who cares?) but I think that even a smallish rock like that would produce some MAJOR damage, and should be avoided at all costs - alomst as much as voting for GW should be avoided.

    RS

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