What if this thing had not been in an Earth-grazing trajectory, but had instead hit full-on, in surface-normal trajectory? Would it have smashed into the ground rather than exploding overhead?
Even if yields are the same effects of nuke would be quite different, no? Meteor dissipates it's energy during several seconds to path of several tens(?) of kilometers. Nuke releases it all in microseconds to one point. Wildly different shockwave ensues.
Incidentally the reason why a lot of Russian news report insists heavily on "low radiation levels", is because that unfortunate region also suffered some huge nuclear disaster back in 1957. http://en.wikipedia.org/wiki/Kyshtym_disaster
Russian news now reporting no fragments found in lake, maybe due to hole in ice formed because of different reason, not impact.See rt.comThis is what they posted:18:40 GMT: The search for the meteorite parts at Chebarkul Lake and at other two locations has officially been stopped. The huge ice hole found at the lake on Friday “has formed because of a different reason,” the Vice-Governor of Chelyabinsk region Igor Murog told Interfax-Ural.
I'm scheduled for a hit on NBC Nightly tonight, with mitigation justifications....
The timing would be coincidental, but not incredible - no doubt the meteor was still supersonic at the time of breakup, so the fragment would at first outpace the shockwave, then slow below supersonic, with the shockwave just happening to catch up to it again at about the same time it hit the ground.
Feb 16, 2013 3-min piece leads the Nightly News [my wrapup at 2:40]http://www.nbcnews.com/id/3032619/ns/NBCNightlyNews/They used only a few direct words from me, but I spent half an hour with the producer and a lot of the narration words are mine, too.[Feb 15 hit on CNBC: http://www.cnbc.com/id/15840232/?video=3000148418&play=1]
In this video (posted previously), the shock wave arrives at 1:10. After the initial startle, the camera is then pointed at a rising cloud of smoke coming from a source hidden by a building. The smoke appears new.See also pictures labeled 01, 02, and 03 on this page showing the zinc factory. Photo 1 shows a similar cloud of smoke as the video:http://zyalt.livejournal.com/722930.html#cutid1Furthermore, all of the damage I've seen so far has been broken windows, and in the worst cases, a couple doors knocked off hinges. No other structural collapses from the shock wave, but in photo 03, the bricks appear to have been scattered pretty forcefully.So I additionally am led to speculate the zinc factory was hit by a fragment, although there appears to be no word on that yet, so my only basis is disbelief that this singular building would suffer so much worse damage than everything else.The timing would be coincidental, but not incredible - no doubt the meteor was still supersonic at the time of breakup, so the fragment would at first outpace the shockwave, then slow below supersonic, with the shockwave just happening to catch up to it again at about the same time it hit the ground.!
In the beginning I thought it was a fragment, too, but Occam's razor suggests the much simpler explanation of the (old?) roof collapsing due to overpressure.
Also technically, a fragment can't outpace a shockwave,
it would produce its own shockwave instead
So the world's reaction to the event can be summed up like this: "Not in our backyard". What saddens me the most that it would take a direct hit with mass casualties until pociticians in power will get their asses up and actually do something about that...
More people die in one month from flooding than in a century from meteors.
Please don’t let The Weather Channel begin naming asteroid flybys.
...which they should... More people die in one month from flooding than in a century from meteors.
Quote from: Blackstar on 02/16/2013 01:58 pmQuote from: yg1968 on 02/16/2013 12:23 pmIf the cost is $500M, it would seem reasonable considering that NASA has a $17B per year budget. This is the kind of work that NASA is expected to do. If NASA doesn't do this kind of work, taxpayers will eventually question whether their $17B per year "investment" into NASA is put to good use. The result is that the money has gotten cut out of other things at NASA, and the agency has never really had the resources to accomplish it.This is just a variation of the common situation of the "unfunded mandate."In your opinion, is this likely to change given the close pass and Russian impact?
Quote from: yg1968 on 02/16/2013 12:23 pmIf the cost is $500M, it would seem reasonable considering that NASA has a $17B per year budget. This is the kind of work that NASA is expected to do. If NASA doesn't do this kind of work, taxpayers will eventually question whether their $17B per year "investment" into NASA is put to good use. The result is that the money has gotten cut out of other things at NASA, and the agency has never really had the resources to accomplish it.This is just a variation of the common situation of the "unfunded mandate."
If the cost is $500M, it would seem reasonable considering that NASA has a $17B per year budget. This is the kind of work that NASA is expected to do. If NASA doesn't do this kind of work, taxpayers will eventually question whether their $17B per year "investment" into NASA is put to good use.
Quote from: Nittany Lion on 02/17/2013 01:36 amPlease don’t let The Weather Channel begin naming asteroid flybys.Why, I think Jim would be a great name
Quote from: iamlucky13 on 02/16/2013 10:23 pmThe timing would be coincidental, but not incredible - no doubt the meteor was still supersonic at the time of breakup, so the fragment would at first outpace the shockwave, then slow below supersonic, with the shockwave just happening to catch up to it again at about the same time it hit the ground.Most videos I've seen don't seem to do justice to the sound and power of that shockwave, ironically it's this low quality video that I think captures it best:I have little trouble believing this kind of thing could explain the damage seen at that zinc factory.
I should add that there's something that Congress could do in an authorization bill that would be worthwhile and would not cost (much) money. They could require DoD to share the data it has recorded on infrared events in the upper atmosphere with scientists who possess the appropriate security clearances. US missile warning satellites regularly record the reentry of space debris as well as meteors. But that data is not made available to the asteroid tracking community so that they can validate their models on how much material enters the atmosphere. That would be a useful thing for them to do.