A friend sent me this from Russia, a pilot took a pic of the#RussianMeteor from the cockpit. Amazing! pic.twitter.com/v3gkBjfo10:11am - 16 Feb 13
Quote from: kevin-rf on 02/17/2013 01:57 amQuote 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 If I die from Asteroid Jim I’m gonna be so upset!
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
Please don’t let The Weather Channel begin naming asteroid flybys.
Quote from: iamlucky13 on 02/16/2013 10:23 pm[...]The explosion was at 40 km altitude, it was still VERY supersonic, and on very shallow trajectory. So, to hit the city the fragments would have to turn almost 90 deg - that's impossible.All the impact sites found so far are at least 80 km from the city.Thanks for this. I was unable to get to sleep still cogitating on the fact I didn't remember anyone saying at what altitude the Meteor exploded. I also noted that early posts seemed to infer that it was Supersonic Fragments causing the Blasts. It's clear that this was a blast from an airburst. Trawling through Youtubes I settled on about 2 mins between the fireball and the arrival of the sonic-blasts, though it's really hard to find continuity in any of the vids. However, 2 mins delay would equate to 40km already seeing Speed of sound in air = 330m/s-1 approx.Спасибо и до свидания на данный момент.
[...]The explosion was at 40 km altitude, it was still VERY supersonic, and on very shallow trajectory. So, to hit the city the fragments would have to turn almost 90 deg - that's impossible.All the impact sites found so far are at least 80 km from the city.
I wonder if part of the reason they no longer share the data (apart from general paranoia) is sharing the data lets an adversary characterize the lower limits and sensitivity of the system along with maybe the scan rate and any coverage gaps that may (or may not) exist. The way around this would be to set a lower limit on what events they share and maybe degrade the data somewhat. So you don't share a 0.1 meter rock, you only do the events that are not large enough to be missed. The 1000 meter rocks
aerial photo:@AstroTerryQuoteA friend sent me this from Russia, a pilot took a pic of the#RussianMeteor from the cockpit. Amazing! pic.twitter.com/v3gkBjfo10:11am - 16 Feb 13
Also technically, a fragment can't outpace a shockwave, it would produce its own shockwave instead - which would have been heard for something big enough to cave in a roof.
There were several fires in the city - all in industrial buildings, and all from heating oil burners damaged by shock wave. Fortunately, they were extinguished in minutes, so that were was not trouble but smoke.NO METEORITE FRAGMENTS hit the city, all the damage is done by shock wave only.
The explosion was at 40 km altitude, it was still VERY supersonic, and on very shallow trajectory. So, to hit the city the fragments would have to turn almost 90 deg - that's impossible.All the impact sites found so far are at least 80 km from the city.
So how much material could be recoverable from this meteor hit?I was reading that there's a big rush to gather pieces and sell them for cash:http://abcnews.go.com/International/russian-meteor-rushing-cash-blast/story?id=18522807
The shockwave from a supersonic fragment probably less than a meter in size probably wouldn't propagate 20+ km
...Quote from: smoliarm on 02/17/2013 12:53 amThere were several fires in the city - all in industrial buildings, and all from heating oil burners damaged by shock wave. Fortunately, they were extinguished in minutes, so that were was not trouble but smoke.NO METEORITE FRAGMENTS hit the city, all the damage is done by shock wave only.Since you're from Russia, I will take your word as having more thorough news coverage than the English sources can provide....
Quote from: RichardAKJ on 02/16/2013 02:41 pmQuote 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?Yeah, probably. But probably only a little bit. To cut to the chase, the US government right now is so dysfunctional that it may not be possible for anything to change, even if it should. If government was properly working, what should happen is that the administration would tie its stated goal of sending humans to an asteroid--for which they are not spending any money--to this new concern and add some money to NASA's budget to fund a space-based survey telescope. (My own view is that they should simply fund the NEOCam Discovery mission proposal. It is not the best way to do the job, but it is probably the most cost effective and least expensive.)But gazing into my cracked crystal ball, here is likely what is going to happen: Congress will hold hearings, they may put some additional language into a NASA authorization bill (one is supposedly in the planning stages), and they may increase the tracking requirement. They may also call for another study of the issue. (That's not a totally bad idea, although I'd suggest that a smarter thing to do would be to implement some of the recommendations in the last NRC study of the issue.) But the authorization bill will not come with additional money attached, and it will be up to the appropriators and the White House to step forward. They _might_ do that. In fact, the White House has been trying to increase the NEO budget for a few years now (from $6 million to about $20 million)--although nobody I know seems to know where that money is supposed to go. But I refer you back to the "government is broken" stuff above. Currently there is language in the NASA authorization act that calls for detection of 140-meter objects that the administration is not funding. Congress can increase the requirement all it wants and the administration can keep ignoring it.I think that one thing that doesn't help a lot is that Rohrabacher is the loudest voice on this subject. He's liked by some space enthusiasts, but he's not treated with much respect by his peers. If you watch the hearings in which he participates, it is clear that many of his colleagues don't take his lead. If a more well-respected member of Congress took on this issue it would have better chances. But broken government, there you go.
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: Blackstar on 02/17/2013 02:21 amI 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.I wonder if part of the reason they no longer share the data (apart from general paranoia) is sharing the data lets an adversary characterize the lower limits and sensitivity of the system along with maybe the scan rate and any coverage gaps that may (or may not) exist. The way around this would be to set a lower limit on what events they share and maybe degrade the data somewhat. So you don't share a 0.1 meter rock, you only do the events that are not large enough to be missed. The 1000 meter rocks
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.
http://blogs.nature.com/news/2009/07/post_30.htmlAir Force to resume meteor data sharing06 Jul 2009 | 16:27 GMT | Posted by Geoffrey BrumfielSpace.com is reporting that the United States Department of Defense (DOD) is rethinking a decision that cut off astronomers from access to data on incoming meteors.The DOD has collected the data with a network of satellites and sensors designed to detect atmospheric nuclear detonations. The same sensors can spot a meteor streaking across the sky, and for over a decade, the military has provided astronomers with some of that data on an ad-hoc basis.As we reported <http://www.nature.com/news/2009/090612/full/459897a.html>, that relationship came to a screeching halt earlier this year, when in March, a memo from Air Force Space Command, which operates the satellites, cautioned against sharing data with scientists. The decision was apparently made because DOD officials were worried that the data could reveal details of the US monitoring system.But now, Brigadier General Robert Rego, the space command’s mobilization assistant to the director of air, space and nuclear operations, says that the organization is considering once again sharing data with scientists, albeit in a more carefully vetted way. The new process will be faster, more systematic, and it in compliance with classification procedures, he says. It could begin within the next few months.
http://www.space.com/6927-military-seeks-common-ground-scientists-fireball-data-flap.htmlMilitary Seeks Common Ground with Scientists on Fireball Data Flapby Leonard David, SPACE.com's Space Insider ColumnistDate: 03 July 2009 Time: 03:10 PM ET<much snip>The flare up about the fireball data release policy has received the attention of U.S. Congressman Dana Rohrabacher, the California lawmaker with a long-time passionate interest in the entire Near Earth Object issue."I have been keeping a close eye on this situation, and I am confident the Department of Defense, in cooperation with the scientific community, will find a solution that permits the release of scientifically valuable data without compromising national security," Rohrabacher explained in a statement to SPACE.com.As for a message to the scientific community, Brigadier General Rego emphasized that there was no intent, and in fact, no change to the data sharing policy. Now underway is a fresh look at ways to improve the relationship and data flow to make it more valuable to scientists."I would encourage you to keep your eye out or your ear to the ground with the scientific community...to see if we haven't done some improvements here over the next few months," Rego concluded.
Quote from: asmi on 02/16/2013 11:00 pmSo 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......which they should... More people die in one month from flooding than in a century from meteors.
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...
If the Chelyabinsk event had been just a little larger, or made of iron
I used average speed of sound of 305 m/sec,