Kerr Watch

Number of days writer Richard Kerr has failed to inform his Science readers of the confirmation of nanodiamonds at the YDB: 3 years, 3 months, and 27 days

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Love Notes: Napier takes down The Bos on disintegrating comets in space; Tusk lends hand

Boslough 2013–Wittke 1313495110 PNAS comet younger dryas Napier.pdf by George Howard

Wittke 2013–Reply to Boslough PNAS comet younger dryas.pdf by George Howard

114 comments to Love Notes: Napier takes down The Bos on disintegrating comets in space; Tusk lends hand

  • Steve Garcia

    Ed -

    It is not your life task to teach anybody anything. That didn’t stop me from asking you to please be specific and clear and NON vague when you comment here obscurely.

    It IS our right to ask WTF you are talking about when you are vague.

    And you just about never have answered simple questions asking for clarity. If YOU bring something up vaguely, we have the right to inquire.

    And, Ed, you are no more an expert on impacts than anyone else here. You are a reporter and a book author, not a scientist. Like I said, a 7th grader can fill values in a scaling formula.

  • Dennis; You forgot the big step up and you did look back

  • Trent Telenko

    Found via Instapundit:

    Russian Meteor, from Birth to Fiery Death: An Asteroid’s Story
    By Mike Wall, Senior Writer |
    December 10, 2013 07:20pm ET

    http://www.space.com/23915-russian-meteor-asteroid-history.html?cmpid=514648

  • Steve; I found more vortex info. Google or bing or internet explorer and type in nelson vortex and there is a detailed explaination of the mechanics of a magnectic vortex. Maybe that can help you out. On another vein, You and I discussed the possiblities of multiple impacts on the Laurrentian Ice Sheet. You stated that multiple hits would string out like Levy- Schumacher did on Jupiter and not cluster in a more localized area. What if the impactor did an airburst closer to the earths surface and some of the impactite was able to strike in a closer surface area AKA shotgun blast. One makes the main strike through the ice and the rest just turn the ice to slush and blow it all over the place. Again I site the Odessea Texas and east central New Mexico fields.

  • Steve Garcia

    Jim -

    My ‘stringing out” thing was that, based on SL-9 fragments impacted over several days and all were on very much the same latitude, I think we can assume that is likely on Earth, too. SL-9 impacts were spread over several days, and were still the same latitude (about 45° south on Jupiter).

    So, I conjecture that if the Michigan impact was multiple fragments, then the impacts would all be at latitude 43°N, but spread out over at least a few hours. Since each hour is 15° of longitude, each hour at latitude 43°N represents about 1525 km. Each MINUTE represents ~25 kms.

    If, like SL-9, the hypothetical multiple Michigan impacts were hours apart, then we are looking at craters around the Earth at latitude 43°N and several thousand kms apart.

    Yeah, the very low altitude airburst/shotgun thing is possible, but not likely. I’d considered that, too, for Michigan, but it just seemed so unlikely that I can’t offer it up myself. Boslough’s fancy cartoon had to do with an airburst just above impact. Airbursts have to do with so many factors – density, angle of descent (including length of time in the atmosphere), size, possible major fractures – that it is all a guessing game on getting one to burst just before impact.

    IMHO, the variables make it so that when two people are talking about an object, they might be talking about two different things and not even know they aren’t talking about the same animal.

    The Chelyabinsk object came in at 15 meters (50 feet) and what was left was only about 2 feet across. Note that it did not “explode” in the normal way; it violently disintegrated over Korkino, but there was still a main body remaining (weighing about 640 kilos when found). It just threw off stuff sloughed off/ablated) much of (or most of) the material that was left at that point. It’s velocity was still so high that the material was luminous as it broke off ans spread out. The breakup was like a high-speed racing boat disintegrating when it crashes. As I see it, the flare-up was because the area of the visible material grew larger as it disintegrated. It had lost most of its material already by that time.

    When they talk about a 500 kt explosion, I still do not know if they are talking about what it would have been if it had ‘exploded’ at its original size or not. Not one of the things I’ve read so far make it clear. I think they are talking about it as if it had been full-sized as it disintegrated over Korkino. The effects were all shock wave, and even then all the damage was done to very brittle and susceptible things – windows, overhead doors, that one poorly constructed roof. You’d be amazed at how little impact force it takes to blow it in, when applied to a large area like a garage door. Or window frames. Many window frames were blown in, with some of the panes still intact. That indicates very weak window attachment was the norm; the grout gave way before all the window panes broke. That is really poor construction, IMHO.

    When I look at 1 psi blast effects of nukes the ranges, for a 500 kt bomb, are considerably short of the distnace from Korkino to Chelyabinsk, so how did they arrive at the blast size? On one calculator online it took 35 megatons for 1 psi to reach much of Chelyabinsk. And that was independent of the height, which I wasn’t able to input. On another it took about 15 megatons. Again, no height input allowed. The higher it explodes, the less the effect is, just due to thinness of the air. Add in the direct line triangulation and it needs even MORE to break windows in Chelyabinsk. Either the calculators are wrong or the current research is wrong (or I am).

  • Steve Garcia

    Oops. That 1 psi blast force I mentioned is the amount of (nuclear) blast pressure for “Slight damage,” meaning broken windows and some injuries, from flying glass mostly. Just exactly what we saw at Chelyabinsk and neighboring towns.

  • E.P. Grondine

    Steve,

    Given your knowledge of impact, everything is “vague” to you.

    That includes the mechanics of the Chelyabinsk airburst, which I also do not have time to teach
    you.

    I won’t even point you to the experts who worked and are working on it. I will point out to you that they do not come by the comments section of the Tusk. Sure, they will send things to George for posting, but that is it. When you have figured out why that is, let me know.

  • Steve Garcia

    Ed -

    Vague? Not anything anybody else writes, because they actually answer questions.

    Look back over your comments. You mention stuff without giving any details about place time whatever. And we are expected to read your mind.

    And your HSIE thing that only you have defined for yourself and expect everyone else to cow tow to.

    PLEASE: Show us ONE other person who uses that term.

    As if you KNOW anything about Chelyabinsk.

    And NO ONE HAS EVER EVER asked you to name your mysterious experts. Haven’t you noticed? We figured when you stopped being a dick you might actually mention a name. And how many REAL names won’t talk to you anymore, because they consider you a gadfly?

  • Steve Garcia

    Ed -

    Oh, and BTW, besides Jonny nobody here asserts that they are experts. I’ve never pretended to be one. Unlike you. And Jonny actually responds to requests.

    Pretend experts are a dime a dozen.

    You are no expert, sir. You are a reporter (or used to be, anyway). One that most actual scientists won’t talk to, for along time now. That is a big handicap, isn’t it? You may know the names of those who work on things, but almost none will talk to you. And you yourself don’t know the science, either. You have almost no contacts,, and no audience. Some reporter.

    Where is your byline these days? No stories? No publishers?

    Not even a blog. A reporter with no audience. They are called waiters where I come from. Or dishwashers.

    I was the only friend you had, and even I couldn’t get you to answer questions. Because you thought I was a numb nuts. But I have more of a science background than you will ever have. I’ve actually been PAID to do research. Have you?

    Now, you DID write a helluva a book. And I give you MUCH credit for that, because it has some very good stuff in it. The science part of it was weak and incomplete, but the rest was good.

  • Trent Telenko

    Steve G,

    The nuclear blast generators assume a Total energy point release.

    Chelyabinsk wasn’t.

    It was a much longer atmospheric impact event, smearing kinetic energy over many orders of magnitude — tens of seconds as opposed to micro-seconds — more time at hyper-velocity.

    Nuclear impact models are garbage-in, garbage-out in terms of calculating either Chelyabinsk or any future Chelyabinsk-like impacts.

  • Steve Garcia

    Trent -

    I know that I myself have a good sense of how much energy was lost at Chelyabinsk in those long seconds prior to the big burst, and that there wasn’t a whole lot left to explode. There have been only one 640 kg chunk and a bunch of little ones left, out of 10,000 tons. Since matter cannot be destroyed except in producing energy in nuclear events/processes, that would mean that about 99.9% of the meteor was gone, ablated away, by the time of the big burst.

    The angle I was going for on the online calculators was not how big it was, but how SMALL it was. And, yes, obviously the online calculators have to use a simplified equation, and I think I know which one.

    But my point right now is that, if those are anywhere near correct, then 500kt simply doesn’t have enough oomph to break windows in Chelyabinsk 25 km away and 23 km below. And I DO think that those calculators are not off by more than 3-fold or so.

    But how MUCH too low? Well, I had to bump the yield up to 43,000 kilotons in order for the 1 psi range to include the downtown area of Chelyabinsk. The US military uses 1 psi as one of their main thresholds, the one that breaks windows and hurts people by flying glass.

    Needing to increase the yield by 86-fold cannot be just the simple GIGO of the online calculators. Someone somewhere has their numbers seriously wrong.

    In addition, at 23 km high the thinness of the air there does a lot to inhibit the effects of a blast. So, taken together, it would seem that they understated the big Chelyabinsk blast.

    I am just following the numbers and trying to make sense of them, knowing they are ballpark numbers.

  • Trent Telenko

    Steve,

    You are still hung up on a unidirectional energy foot print from a point event. Just because you got a 1 psi wave front at downtown area of Chelyabinsk. Don’t think that the entire wave front has to be that in every other location.

    Think in terms of explosive shaped charge. In fact, think in terms of _multiple_ explosive shaped charges going off over tens of seconds.

    There were all sorts of wave front additions and shadows in a general direction and downtown area of Chelyabinsk happened to be a strong additive shockwave area.

    IFAIK, there are no such nuclear level explosive yield models for such interactions anywhere.

  • E.P. Grondine

    “One that most actual scientists won’t talk to, for along time now.”

    Wrong.

    “You may know the names of those who work on things, but almost none will talk to you.”

    Wrong.

    “And you yourself don’t know the science, either.

    Wrong.

    “You have almost no contacts, and no audience.”

    Wrong.

  • E.P. Grondine

    Hi Trent –

    The explosion was measured.
    At about 540 kt, if memory serves.

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