The enormous meteorite explosion over Russia offers the strongest motivation yet for investigation of near-Earth objects.
For those who follow the asteroid impact threat, the 300- to 500-kiloton meteor blast over Russia on February 15th was just a matter of time. It shone brighter than the Sun, and when the shock wave swept across cities and towns more than a minute later, it blew out countless windows and injured at least 1,100 people, mostly by flying glass; see many more Russian videos and photos. At least one large meteorite fragment accompanied by small black pieces landed in a lake near Chebarkul, a town in the Chelyabinsk region. As astronomers are keenly aware, Earth sits in a cosmic shooting gallery. Every day, grains, pebbles, and chunks left over from the formation of the solar system streak into the upper atmosphere. Most vaporize very high, causing no harm and giving us beautiful shooting stars.

Meteorite smoke

The fireball left a record-breaking train across ther daytime sky.


Nikita Plekhanov
But occasionally, perhaps every few decades to few centuries, our planet gets smacked by an object big enough to cause substantial damage. That's what happened February 15, 2013, at 9:20 a.m. local time in the Ural Mountains of west-central Russia (3:20 Universal Time). More news reports.

According to analysis by meteor expert Peter Brown (University of Western Ontario), the incoming meteoroid carried about 300 kilotons of kinetic energy (about 20 Hiroshimas), entered Earth’s atmosphere at 20 kilometers per second (typical for near-Earth asteroids), was about 15 meters (50 feet) across, and weighed about 7,000 tons. It entered the atmosphere at a grazing angle of less than 20° and burst at a height of 15 or 20 kilometers (10 or 12 miles). An early track-back analysis has put the outer end of its former orbit in the asteroid belt.

(UPDATE: Later in the day NASA released its own estimates: a 10,000-ton object and 500 kilotons of energy.)

This makes it the largest object to hit Earth since the Tunguska event in 1908, beating the Sikhote-Alin meteor in 1947 (also in Russia).

What will probably go in the books as the "Chelyabinsk meteor" fragmented near the city of Chelyabinsk and south of Yekaterinburg. The shock wave shattered glass in at least six cities and towns. Fortunately, we have heard no reports of fatalities, but several dozen people were hurt badly enough to require hospitalization. Obviously, our thoughts and prayers go out to these people, and we wish them a speedy recovery.

Watch another video of the incoming fireball:

By an amazing cosmic coincidence, the impact occurred just 16 hours before the predicted flyby of the larger asteroid 2012 DA14. Because the two objects were moving in completely different directions, there’s no chance the two events are related. "This meteor event is in no way related and can't be associated with DA14," says Dan Durda (Southwest Research Institute). "It's complete coincidence." But this one-two combo should serve as a wake-up call that we need to take the impact threat seriously. Unlike today’s object that broke up over Russia, 2012 DA14 is large enough that it could cause widespread destruction if it actually hit our planet.

Meteorite video stills

These stills were pulled from an uncredited video at LiveLeak.com, showing the sudden appearance of a fireball out of a clear, blue sky.


http://www.liveleak.com/view?i=152_1360906606
With the dramatic video footage, hundreds of injuries, and mass media coverage, I hope and expect that today’s meteor explosion over Russia will serve as a watershed event in public understanding of the impact threat. Astronomers have been warning us for many years that we need to take the impact threat seriously.

Fortunately, astronomers (mostly in the U.S.) have received sufficient funding and resources that they have identified almost all the kilometer-size near-Earth asteroids that could wipe out civilization, such as the 10-km asteroid that triggered a mass extinction 65 million years ago (extinguishing all dinosaur lineages except birds). None of these large objects will hit our planet in the foreseeable future.

But smaller bodies remain a concern. As a case in point, on June 30, 1908, an object a few tens of meters across exploded over the Tunguska River region of Siberia — flattening 800 square miles of forest. If that object had exploded over a populated area, it could have killed hundreds of thousands of people.

I often wonder what would have happened if the Tunguska impactor had exploded over the Soviet Union in 1958 or 1968 or 1978 rather than 1908. Given the Cold War hostility and tensions at that time, would the Soviet government have started to lob nukes at the U.S., triggering thermonuclear Armageddon? On the morning of the new meteor, Russian nationalist leader Vladimir Zhirinovsky was immediately on the news deriding the idea that it was a meteor and claiming that it was an American weapons test. And what about meteor explosions over other nuclear-armed nations? The U.S. Air Force has systems that can quickly distinguish a blazingly fast incoming asteroid from a relatively slow ballistic missile, but most nations lack such resources.

Though I deeply regret that people in Russia were hurt by this event, I hope humanity can draw the proper lessons. The “good news” is that it was big enough to serve as a wake-up call, but not big enough to kill people. I don’t stay awake at night worrying about asteroid impacts, and neither should you. Other potential disasters, both natural and man-made, rank far higher on the list of “things you should worry about.”

But the interesting aspect of the impact threat is that unlike earthquakes, volcanoes, and other natural disasters, we can actually do something about meteor impacts. We can find these objects, we can track their motions, and we can predict their orbits many years into the future. And in the unlikely event that we actually find a dangerous object on a collision course with Earth, we might actually be able to deflect it if given sufficient warning time. Now, every government in the world is keenly aware of the possibility of meteor explosions over its territory.

Comments


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David

February 15, 2013 at 7:54 am

Interesting article and a good topic for discussion on a day like today, Feb. 15, 2013. However, I would like to offer a bit of constructive criticism; please refrain from using the bromide "thoughts and prayers" in a scientific magazine such as this. Talking to imaginary beings is more associated with astrology than astronomy.

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Jeff

February 15, 2013 at 8:02 am

Perfect timing on posting this.

I was just about to go on air with local media and loaded this page and found yesterdays article. Just as I was going live I hit refresh and this new article was posted and I was able to skim and grab the details on the run.

Again perfect timing and thanks Sky and Tel for continuing to be a timely source of information....and for pulling my rear end out of the frying pan as I was just getting out of bed when the media called and hadn't even heard the morning news yet.
Jeff

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Patrick

February 15, 2013 at 8:23 am

Here's hoping that David will respect those for whom faith and reason are different, but compatible, ways of knowing the universe.

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Fred from Laurel, Md

February 15, 2013 at 8:58 am

... about such events. Several things come to mind.
• Almost 1000 injured (awful!) & no deaths (a very good thing!).
• At 10 tons, it must have been 1 or 2 meters.
• Is there any conceivable program that could have detected a body this small in time to warn the target area?
• Speculation about Tunguska-type event moved forward 6 or 7 decades -- they already had ways of distinguishing nuke tests from natural sesmic events; did they not also have ways to tell a meteor air-burst from a nuclear one?

And finally, to David: I'm not religious, but I have no problem with that phrase. This forum is not ApJ, AJ, PhysRev, Science, Nature, or even SciAm. It is partly scientific, partly journalistic, and human reactions are expected here. If you don't understand religion, that's fine -- you are under no obligation to understand it. But please don't criticize those who may, over such trivia.

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Reilly

February 15, 2013 at 9:16 am

Dave, jeez dude, you gotta let it go man and lighten up. Thoughts and prayers are a positive human gesture no matter how high of holy jumper the person is. ANYWAY...WHY DOES THE VIDEO SAY 31-12-2012? I would assume someone just doesn't know how to set his camera clock correctly, right?

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Reilly

February 15, 2013 at 9:18 am

David you got let it go man, lighten up. "Thoughts and prayers" are a positive human gesture no matter how high of holy jumper the person is. ANYWAY...did anyone realize the date on the video is not today? I would assume that someone just didn't know how to set his camera date/time correctly...right?

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Marcus

February 15, 2013 at 9:26 am

I would like to offer a huge amount of constructive wisdom to support the thoughts and prayers that go out to those injured today.

Instead of falling may our thoughts and prayers continue to descend

Down to the ground of this Earth bearing unconditional love till the end

While the sound of these blessings in the form of thoughts and prayers lift the fallen up above the wind

Back around again looking to inform each other but also show we care for strangers in need of a homepage news writer but also a thoughtful friend

When they're hurt and not able to find peace humbly do we offer words on which we can depend

Will bring forth thankfulness instilled in those human beings injured with the simple thoughts and prayers we send

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Daniel

February 15, 2013 at 11:25 am

Interesting story. I always hope I could be around a meteor when it falls to Earth. Does any one know what those three lights are on the picture on S&T main page.

@David:"Consequently I entreat you by the compassions of God, brothers, to present your bodies a sacrifice living, holy, acceptable to God, a sacred service with your power of reason." Romans 12:1 NWT

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Anthony Barreiro

February 15, 2013 at 11:53 am

Robert, thanks for this exceptionally timely and thoughtful article. And David, I also offer my thoughts and prayers for those who were injured in this disaster. We probably all mean something different by the word "prayer". I respect your right to your beliefs; please don't try to censor Robert or me in our beliefs.

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Anthony Barreiro

February 15, 2013 at 11:53 am

Robert, thanks for this exceptionally timely and thoughtful article. And David, I also offer my thoughts and prayers for those who were injured in this disaster. We probably all mean something different by the word "prayer". I respect your right to your beliefs; please don't try to censor Robert or me in our beliefs.

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Dennis Mabrey

February 15, 2013 at 12:06 pm

"This meteor event is in no way related and can't be associated with DA14," says Dan Durda

Maybe I skimmed this too fast but I don't see a reason why it is in no way related? On what grounds do you dismiss such a thing?

Many impacts on the moon and the famous Shoemaker Levy comet that hit Jupiter were made of multiple fragments.

At least say WHY it can't be the same. Have they recovered any of the fragments?

This isn't passing the smell test and his statement leaves more questions than answers.

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Danny

February 15, 2013 at 4:11 pm

Great article Robert. Praying for the quick recovery of all injured.
@david. I suppose you don't approve of freedom of religion or speech. But by that I have to allow you your opinions. And you ours.

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John E.

February 15, 2013 at 4:18 pm

The three lights that were asked about above ( by David at 10:25) look like they are there because the photograph was taken though a window. Either their is a light source with three parts on the side of the glass that the photographer is on, or it is a double paned window and we are seeing multiple reflections of a single light source.

I enjoyed the article, including the personal reflections.

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jwp63

February 15, 2013 at 4:26 pm

...the comments here have been dominated by David's quite justifiable comment. Here is a vote of support for his expression of that opinion and its sentiment. ... Moving on to more pertinent matters, congratulations, indeed, to Robert on a fine article. I've read a dozen or so on the Russia meteor, and this is easily the most informative. Bravo.

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Joseph Slomka

February 15, 2013 at 5:18 pm

Robert,

You are the first one today to mention the coincidence of the three biggest
meteors of the 20th and 21st Centuries landing on Russia:
Tunguska, Sikhote-Alin and now Chelyabinsk.
Unfortunately, Siberia is not as empty as it used to be.

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Jose Borrero

February 15, 2013 at 5:35 pm

It was about three days ago that I heard and saw two big flashes that sound like thunders similar to the two years ago meteorite that enter U.S best seen over wisconsin skies. I woild say that was in the same position area of the sky when happened. Anyone know about it?

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William

February 15, 2013 at 6:11 pm

Daniel ("Does any one know what those three lights are on the picture on S&T main page.") -- They appear to me to be reflections in a window through which the photograph was taken.

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Bruce

February 15, 2013 at 6:33 pm

Yes, it was a great article David. I first became aware of this event at 7 AM (CST) this morning as it was the lead story on the NBC Today Show. Matt Lauer had a too brief interview with Neil deGrasse Tyson who stated that this event was definitely NOT related to the coming asteroid flyby, but then he failed to state WHY they knew these events were unrelated. Then the last thing he said was “this is not related to the asteroid that will HIT later.” I’m sure he didn’t mean to say that asteroid 2012 DA14 was going to hit anything today, but that was the last thing he said! Naturally Matt failed to question this amazing statement. I quickly searched several websites (This story here hadn’t posted yet) until reading that the Russian asteroid had come in from a very different direction than the south to north track that 2012 DA14 was due to take, which, to answer Dennis Mabrey’s question, provides sufficient evidence that these two events where “complete coincidence.”
Also, my thanks to Patrick, Fred, Reilly, Marcus, Daniel, Anthony and Danny for defending Robert Naeye’s very appropriate “thoughts and prayers” statement. May those hurt today recover quickly.

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Brooke

February 15, 2013 at 6:33 pm

Wery well epressed article regarding this event. It is amazing that this event happened so close to the expected pass of asteroid 2012 DA14. I also noticed the incorrect date and time stamp on one of the videos shown. I imagine they must have not set their clock correctly. I do wonder how there are so many videos of the event from cars. Are they cabs or is that common in typical Russian cars? Regardless, I am glad they got the footage. It is sad that many people were injured, but considering the power of this event, it could have been much worse. I hope that we can make progress in identifying objects such as this quick enough to prevent them from creating damage or to provide warning to those in danger.

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John

February 15, 2013 at 6:44 pm

I agree with David's post. However, I understand the author, Robert, was just saying he hoped the victims would be ok.

Still, Roberts gets paid to write, and he could have respected EVERYONE'S beliefs by not suggesting that the rest of the staff were on bended knee with him. If he had simply said "We wish them a speedy recovery" we'd all be ok with that. That part was certainly nice and showed humanity.

I would add that when he said "we" I am presuming Robert was not referring to the entire readership, given the prevalence of atheism in the scientific community. Many certainly would have an issue with being lumped in as believers, even in a country like the USA where people are frequently pilloried, online and otherwise, if they say they don't believe. Of course, not literally in America - anymore.

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Widebandit

February 15, 2013 at 8:42 pm

Nature ever so gently reminds us of the true magnitude of the energy moving about our solar system. This will undoubtedly advance our understanding of the Tunguska blow-down by orders of magnitude. We now have a practical example to guide us.

Vladimir! Get a life! Expand your horizons! Take a few AST100 courses! There’s much more to our universe than nuclear-geo-political paranoia. Surely you must know that nature has the ability to make mankind's entire nuclear arsenal seem like so many small fire-crackers.

David, my thoughts and prayers are also with those affected by this event. In fact, I can see where it may even shed light on such peculiar historical accounts as the destruction of the Amorite coalition recorded in Joshua chapter ten – hail-stones or meteor-stones - whaddya think?

- wa -

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Dan K

February 15, 2013 at 8:58 pm

This has become a hackneyed and pro forma phrase used mainly when political figures feel compelled to pretend to care about some particular tragedy somewhere. As such, this perfunctory reference has become meaningless and can easily be dispensed with, and forthwith.

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TheDarkHorseOne

February 15, 2013 at 10:25 pm

That video with the sound is incredible. Anyone know the blast radius of effect? Has that been calculated yet?

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Michel

February 16, 2013 at 12:26 am

Thanks David for your vigilence.
We are far more likely to get kill by irrational human beings than by errant asteroids.

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Paul Cox

February 16, 2013 at 3:22 am

I tracked and imaged Near-Earth Asteroid 2012 DA14 for much of the night.

I created a time-lapse made up of over 100 of the images. There is more info, and the video itself, here: http://plus.google.com/u/0/113293976957750950702/posts/hrn4DxN2tKu

We held four live shows throughout the night to track not only 2012 DA14, but also the other NEO that was making its closest approach - 2008 DG17.

.

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Mike

February 16, 2013 at 5:26 am

I don't recall the title but an interesting science fiction short story in the 50s was about a man at a desk getting the information about an explosion destroying NYC and having to make a launch/don't decision on a retaliatory nuclear strike. In the story it turned out to be a significant meteor impact. That theme was used in a few other places as well.

The two events shouldn't be that hard to tell apart even without instrumentation, if you know to look for the differences. The airburst break up of a meteor appears to leave fragment trails in the sky after the flash, which I don't believe would be present after a nuclear airburst. I am certain there are several easy to identify signatures.

Ignoring any religious questions,I certainly wish the people injured in this incident well.

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Bruce

February 16, 2013 at 7:34 am

Dan K, you might be surprised to find that I agree completely with your first sentence: “This has become a hackneyed and pro forma phrase used mainly when political figures feel compelled to pretend to care about some particular tragedy somewhere.” I’ll go even further down that road and state that even when some religious leaders use this expression at tragic occasions they too are being hypocritical, since some use tragedies to enrich themselves on donations. Such ones are among the many today who are “having a form of godly devotion but proving false to its power” 2 Timothy 3:1-5. But Robert Naeye is neither a politician nor a member of the clergy, (and nether am I, BTW) and I think his use of the expression was a sincere attempt to show human kindness. The fact is that if he had omitted the word “prayer” from his article this debate wouldn’t have occurred. What we have here is an attempt to expunge any mention of anything having to do with God from these discussions, but God’s existence is a scientific question upon which astronomy has much to tell us, so I don’t thing banning certain words is constructive.

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CindyG.

February 16, 2013 at 8:04 am

Thank you Robert for a great article. The videos were amazing and scary at the same time. It really is a reminder of what has been going on for millions or billions of years in our solar system.

@David, may I offer constructive advice to you: Let it go. And if you want a pure scientific magazine with no "thoughts and prayers" within it's pages that may offend you, then I advise you to start publishing one of your own. This is Roberts article, he has a right to use any words he sees fit.

BTW, my thoughts and prayers are with the everyone affected by this event.

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Jim

February 16, 2013 at 8:43 am

While listening to reports of the Russian boliode yesterday on the internet and TV, they seemed to be making contradictory statements concerning the trajectory of the object. One reported that the boliode was traveling east to west, another claimed it was north to south. Both reports claimed with certainty that this wasn't related to 2012 DA14, but provided no further information to either support or deny that conclusion. It is unclear as to why the reported trajectories don't match, or how they can say with any certainty it wasn't related to 2012 DA14. Was there was a conspiracy to keep the public calm, or was the matter unclear or misunderstood by the media?

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Fred from Laurel, Md

February 16, 2013 at 11:34 am

Those who have pointed out that we repeatedly hear that this bolide and DA14 are unrelated, without any explanation why this is so -- yes! This is a common failing when events unfold faster than the experts can craft cogent explanations of them, and it tends to get neglected, so it remains a nagging question in the minds of many.

My own (fact-starved) take is this.
If you look at the sky chart of DA14's track, it is very decidedly south-to-north.
If you watch those videos in which it is clear the Sun is located, you can see that the bolide appears to emerge almost directly out of the (rising) Sun; thus, it traveled east-to-west.
These velocity vectors (I trust that their magnitudes would also support this), and note that they are both based in the Earth-frame, are probably disparate enough to make their pre-encounter solar orbits different enough to rule out a connection.

But I would like to hear what the actual situations were!

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Keith

February 16, 2013 at 1:37 pm

I have often wondered what would happen if there were a Tunguska type event in the vicinity of one of the worlds 440 nuclear power plants, double whammey -

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Bruce

February 16, 2013 at 2:01 pm

Nice comment CindyG. To all with nagging doubts about the totally unrelated natures of yesterday's two asteroidal events here are two links that I found in the APOD and General Astronomy Discussion Forum that may help to clear things up: http://s.telegraph.co.uk/graphics/html/Years/2013/February/images/Meteor5.png
and
http://blogs.agi.com/agi/2013/02/15/russian-meteor-crash-animation-from-agi-unrelated-to-asteroid-2012-da14-close-approach/
To Fred, you worked it out for yourself and your logic is sound. And to those who are wondering why Russia is taking all these big hits (1908’s Tunguska event, 1947’s Sikhote-Alin meteorite and yesterday’s) the explanation is no deeper than Russia’s vast size. Russia is by far the world’s largest nation, so it’s the most likely to be impacted.

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Todd Robert

February 16, 2013 at 3:57 pm

You know, you all could have just lightened up yourselves and let his comment pass. I'm with David....although "thoughts and prayers" is commonly used and meant to be nice...it's not science. Sending thoughts (not religious) and prayers (religious) is pointless.

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Tom D

February 16, 2013 at 5:40 pm

You wrote 'Other potential disasters, both natural and man-made, rank far higher on the list of “things you should worry about.”'

One should agree, if we are only thinking about ourselves or those we know. But when we think about our global civilization and its extention to future generations then we need to rank this threat far higher than we do. We already know in this broad actuarial sense that asteroids are more dangerous than motor vehicles. So, please, we need to retain our appearance of 'reasonableness', bt not at the cost of abandoning the statistical truth of what science teaches us.

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Jim Buja

February 16, 2013 at 7:37 pm

A realization came to me when I was watching the numerous excellent videos of the meteor. Did it really explode near the end or did it simply break into pieces? Except for the incredible brightness and oversaturation of video I see no evidence of an explosion. With all the kilotonage and nuclear references people just assume it had to have exploded. I have doubts. The sonic boom/shockwave of its passage might be all there was to it. The eventual spread of fragments locations might confirm or refute the Explosion Hypothesis. What do people think? Take a other look at videos .. especially slowed down ones.

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Felipe Hodar

February 16, 2013 at 8:22 pm

Great article! Unfortunately the post comments should be disconsider because we are not here to discuss if you are beliver or not! We ate here to read and know more Astronomy.
Congrats Sky writers and all commited to give us a fully cover of this important and remarkable event.
God bless all!

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Frank Reed

February 16, 2013 at 9:16 pm

Jim Buja, you wondered whether it "really exploded or just broke into pieces". It's the same thing here. This is not an explosion in a chemical sense. It's a very rapid transformation of the object's kinetic energy into thermal energy and light. It occurs when a body like this rapidly disintegrates due to the extreme pressure of hot air on the entry side and also the high stresses from decelarations greater than 100 g's. Most meteors (tiny asteroids) are believed to be rather fragile objects, some only loosely held together. When they break apart, the amount of surface area exposed rapidly increases and the pieces rapidly decelerate releasing a tremendous amount of energy in a very short period of time. That's what's meant here by an "explosion". It's not a perfect word, but it does apply.

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Frank Reed

February 16, 2013 at 9:23 pm

I do not agree that the astronomical community should see this as an opportunity to get funding for meteor risk. This was the only serious meteor incident in a hundred years, and very close to a big city. And yet even so, no one was killed, only a few dozen people were hospitalized and damage is on the order of $50 million dollars, less than a minor tornado (contrast that with the $50 BILLION bill for Storm Sandy). It may be possible to do something on the cheap. For example, military radars could certainly detect objects in this range and might give an hour's advance notice. We have tsunami warnings. Perhaps we should have "fireball" warnings. For this to happen, a system would have to be created to get military data into the hands of a civil organization tasked with issuing such alerts. That would be tough but not impossible. If Russian media had broadcast an alert at 9:00am saying "Meteor shock wave alert: stand clear of windows and doors from 9:15 to 9:30", many injuries could have been avoided. But with such rare events, it's possible that the cost from false alarms could exceed the value of the alerts themselves.

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Frank Reed

February 16, 2013 at 9:26 pm

The evidence is very strong that there was no relationship between the close approach of "2012 DA14" and the Russian meteor. But that is astounding! Is the universe messing with our heads? Coincidences like this have been known to drive people mad. Expect a thousand conspiracy theories for decades to come...

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Jim Buja

February 17, 2013 at 7:34 am

Frank,

Thank you for the explanation of the explosion/disintegration/breakup. That makes sense. Yes I know it is not a chemical explosion -- or even due to heated gases/water inside the meteor (althogh I suppose some might have that too?)

Also I understand it is nit exactly 'friction' causing the heating rather it is the tremendous compression of the air shockwave built up in front of any object entering the atmosphere and the heat is transferred to and around the object (and the heated air actually becomes a plasma right?).

I did notice that some news notes called it simply a Meteor breaking up over Siberia etc... At least the less sensational ones did ;-))

Explosions sell papers I guess !!

Jim

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Bruce

February 17, 2013 at 9:57 am

To Todd Robert and all who may agree (or disagree) with him, Robert Naeye’s complete statement which is being both criticized and defended was, “Obviously, our thoughts and prayers go out to these people, and we wish them a speedy recovery.” Expressing sympathy is an ordinary humane reaction. Without such caring thoughts no helpful actions would ever be taken, and this would be an even more heartless world that it is. And the main point he was making is that more thought needs to be put into addressing the threat of NEO impacts. As to the “prayers” part, well, that’s pointless only if there is no “hearer of prayer.” (Psalms 65:2) Atheists have the right to disbelief and to expresses that disbelief, but believers in God also have such rights. The Bible encourages people to “pray for one another” (James 5:16, and see also vs. 13-18 which discusses prayer) so praying in behalf of our Russian brothers and sisters is by no means pointless.

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Fred from Laurel, Md

February 17, 2013 at 2:15 pm

Frank: "Is the universe messing with our heads?
- - YES! - -
And it does so all the time, which is partly why we're so smart about astronomy!

That at least, was one of the ideas in a book (a sort of coffee-table book for high-schoolers) I have, about astronomy, by Fred Hoyle, written in the 1960's. His particular thesis about the complexity of the motion of the Moon was, that it was challenging on increasing levels, not so much as to discourage all attempt at explanation, but that some part of it was just enough beyond the reach of the day, for several centuries, that it spawned a lot of the development of mathematical analysis.

It is an idea that has stuck with me, as it may now do with some of you.

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Richard Loosemore

February 17, 2013 at 6:39 pm

Has anyone done calculations to see if the three meteors observed recently had similar trajectories?

Obviously, the meteors were not connected with the asteroid, but I have seen no comparison of the three events in Russia, Cuba and San Francisco.

Just wondering.

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kkrumm

February 18, 2013 at 11:13 am

These meteorites/meteors seem to have an affinity for Russia. Paybacks for Laika? Any reasonable idea of why Russia seems to take the big hits?

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Jim Buja

February 18, 2013 at 12:41 pm

KK,
Yes you have to wonder about meteors and Russia. With risk of this thread being hijacked by nutcases, my theory is that somewhere someone has positioned a deflection device that is steering all larger meteors either to pass by us .. hit the moon .or hit mostly uninhabited parts of earth. What do you think? Hey if we ever get such technology ourselves and then move on to discover inhabited worlds what do you think we would do with such tech? Set it up to protect fledgling words from planet killers...
Could be we are the fledglings ...
J

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john

February 18, 2013 at 5:57 pm

realy??? david is right you all should get a grip

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Robert Casey

February 20, 2013 at 11:36 am

There was this old civil defense training film "Duck and Cover" aimed at how to protect yourself from nuke bomb blasts. Sure, at ground zero you'd be toast, but a few miles away, due to the speed of sound and shock waves being much slower than light, you have maybe 10-15 seconds to duck and cover under a table or desk ir an inside room. To protect against flying broken glass. From nuke bombs or the more common meteors.

This was a very rare event, but planting "Duck and Cover" in the back of peoples' minds might reduce the injuryies.

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Stephanie Stipp

February 21, 2013 at 3:14 am

On Friday after the Russian meteor, I was outside about 10pm
watching a police helicopter circling a couple blocks from my home. Out of the corner of my eye I saw something and turned, it was a meteor traveling from North to South, I was facing East I saw it break up as it streaked by. I don't believe it hit the earth because I never heard anything about it the next day. But it sure a coincidence isn't it?

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Pete

February 23, 2013 at 11:34 am

After all the condemnation over their recent tests, we should be thankful that it didn't occur over North Korea !

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