A Meteorite exploded above the town of Satka, near the city of Chelyabinsk in Russia.
Image: YouTube/RyanNorthover
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A meteor that exploded over Russia this morning was the largest recorded object to strike the Earth in more than a century, scientists say. Infrasound data collected by a network designed to watch for nuclear weapons testing suggests that today's blast released hundreds of kilotons of energy. That would make it far more powerful than the nuclear weapon tested by North Korea just days ago and the largest rock crashing on the planet since a meteor broke up over Siberia's Tunguska river in 1908.
"It was a very, very powerful event," says Margaret Campbell-Brown, an astronomer at the University of Western Ontario in London, Canada, who has studied data from two infrasound stations near the impact site. Her calculations show that the meteoroid was approximately 15 meters across when it entered the atmosphere, and put its mass at around 40 tons. "That would make it the biggest object recorded to hit the Earth since Tunguska," she says.
The meteor appeared at around 09:25 a.m. local time over the region of Chelyabinsk, near the southern Ural Mountains. The fireball blinded drivers and a subsequent explosion blew out windows and damaged hundreds of buildings. So far, more than 700 people are reported to have been injured, mainly from broken glass, according to a statement from the Russian Emergency Ministry.
Despite its massive size, the object went undetected until it hit the atmosphere. "I'm not aware of anyone who saw this coming," says Heiner Klinkrad, head of the European Space Agency's space debris office at the European Space Operations Center in Darmstadt, Germany. Although a network of telescopes watches for asteroids that might strike Earth, it is geared towards spotting larger objects — between 100 meters and a kilometer in size.
"Objects like that are nearly impossible to see until a day or two before impact," says Timothy Spahr, Director of the Minor Planet Center in Cambridge, Massachusetts, which tracks asteroids and small bodies. So far as he knows, he says, his centre also failed to spot the approaching rock.
The meteoroid itself was likely made of actual rock, but may have also been made of nickel and iron. Campbell-Brown says it probably came from the asteroid belt, a region containing hundreds of thousands of rocky bodies and located between Mars and Jupiter. ESA does not believe the meteor is related to a much larger asteroid known as 2012 DA14, which will be passing within about 20,000 kilometers of Earth later today. Both the timing of the meteor's appearance and its location indicate it came from a different direction, Klinkrad says. Campbell-Brown agrees: "We happened to have close approaches to two of them, and one of them got us," she says.
Although there are reports of fragments of the meteor, or meteorites, striking the ground, Klinkrad says that he believes the vast majority of damage in the region was caused by shockwaves of the explosion, as the rock broke up in the upper atmosphere. Campbell-Brown says that the infrasound data shows a very shallow angle of approach — a feature that funneled much of the energy from the blast to the city below. Still, she adds, "It's lucky that there wasn't more damage."
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35 Comments
Add CommentFascinating!
Reply | Report Abuse | Link to thisThat video could not be better if it was choreographed by Hollywood. It looked like they were taking in the sunset or just documenting their trip. Amazing luck.
I hope we see more follow up.
Early comments are that this meteor and the big one coming later today are unrelated. Given the emptiness of space, that seems improbable. It will be interesting to see if the orbits of these two bodies really are dissimilar.
Reply | Report Abuse | Link to thisActually, dashboard cameras are very popular in Russia as a tool to document the notoriously bad driving of others in case of a collision. So there are several videos circulating that were captured from highways by dashboard video cameras that record all the time.
Reply | Report Abuse | Link to thisApparently a meteor of this size hitting Earth happens once a year on average, so this may not be as improbable as you think. It sounds like the trajectory of this meteor is very different than the flyby object's.
Reply | Report Abuse | Link to thisRegardless of the directions of approach, the probability of unrelated, random occurrence of two very rare asteroid events in the same 24 hour period would likely be prohibitive, indicating a more likely causal relationship - even if we do not understand what the causation might be.
Reply | Report Abuse | Link to thisI'm not a statistician, but wouldn't the probability of a a single 100 year event be 1/36500? Wouldn't the probability of two 100 year events occurring in the same 24 hour period be 1/(36500^2)? My math is likely incorrect, but I bet that the correct probability is of similar magnitude...
What's your source?
Reply | Report Abuse | Link to thisA legislator in North Carolina is likely working feverishly on a new bill to outlaw meteor strikes.
Reply | Report Abuse | Link to thisYes, the probability in theory would be (1/36524)^2 if indeed these were two 100 year events. But given that, I have had four 100 year floods hit my businesses over the years too, LOL!! I am a bit skeptical of claims of confidence intervals with regard to MTBO when our sample size is smaller than the mean time between occurrences we are estimating to begin with.
Reply | Report Abuse | Link to thisPlus, yes the likelihood of this occurring might be remote, but then again there are SO many unlikely events that eventually some of them happen. Such is the nature of statistical occurrences.
I love this, it is simply fascinating. Sorry for the damages to the Russian homes and businesses. What the heck does the caster of meteors have against Russia anyway?
Reply | Report Abuse | Link to this- TES 8-)
Recent climate models confirm that these events will only become more extreme and frequent as we pump evermore tons of carbon into the atmosphere.....
Reply | Report Abuse | Link to thisSarcasm, I hope?
Reply | Report Abuse | Link to thisMore videos keep popping up, youtube and news channels. Great show!
Yes, I do appreciate your point about statistical evaluations applied to small sample populations. However, there's some reasonable probability that two 100 year flood events could occur within days of each other some spring when heavy winter snow accumulation melts up North, for example.
Reply | Report Abuse | Link to thisHere we have two events that may be related since both objects likely originated in the asteroid belt. Even if they arrived from different directions, there is some possibility that they left the asteroid belt following a collision there and have arrived from different directions at very nearly the same time having taken separate routes to get here - for example.
If one arrived from a near Earth orbit, perhaps it could have been perturbed by the larger asteroid, taking an orbital path to impact, for example.
IMO it's simply not appropriate for scientists to dismiss all potential causal relationships between two asteroid events simply because they aren't arriving from the same direction. The odds against them are great, and, obviously, not everything is known...
OK that's the most absurd thing I've ever heard! How is more or less carbon in the atmosphere going to increase extremity and frequency of earthbound meteors .....Please don't pump evermore tons of propaganda into a subject
Reply | Report Abuse | Link to thisthat is already not being taken as seriously as is needed.
@jtdwyer: Please note that there were rather more than (1/36524)^2 - 1 coincidences that did not happen today; this is just one of the ones that did occur. Also please note that once an event (or coincidence) has occurred, it's 100% likely to have occurred.
Reply | Report Abuse | Link to thisAs Geoffrey Grimmett over at Plus Maths puts it:
"Think of it this way. There is a great number of events which could possibly occur (N, say) and which might deserve the title "coincidence". Each of these may have a very small probability of occurring in any given week (p, say). Now N is large, and p is small, but the average number of occurrences (i.e., the product Np) may be of reasonable size. It follows "by the laws of chance" that coincidences will definitely occur sooner or later. Indeed, the world would be more surprising if coincidences never occurred."
http://plus.maths.org/content/what-coincidence
These things pack tremendous power.
Reply | Report Abuse | Link to thisIt's surprising no one was killed.
These probably can't be predicted, and the explosion in the kiloton range is pretty frightening.
There is always the concern such an event will be mistaken for a nuclear attack and set off a retaliatory strike.
Hopefully the fingers are off the hair trigger now.
Do you remember "Launch on warning"?
How many minutes now on the doomsday clock maintained by the society of atomic scientists.
I think he is joking
Reply | Report Abuse | Link to thisLucky this one wasn't equal to the Tunguska of 1908.
Reply | Report Abuse | Link to thisThat one exploded in the air also and leveled hundreds of square miles of forest.
If this one was as destructive those cities would also have been leveled and probably thousands of casualties would have resulted.
Again, I'm no math plus but IMO Geoffrey Grimmett's discussion is appropriate for unrelated coincidence, such as my being killed by and asteroid on the day I win the lottery. Any random event can occur coincidentally with any other without inferring potential causation.
Reply | Report Abuse | Link to thisHowever, IMO when two very rare but potentially related events such as large asteroids, both likely originating in the asteroid belt, arrive in Earth's space on the same day, all possible causal relationships should be carefully evaluated. That is, if you're interested in understanding why asteroids arrive in Earth's space...
1 out of 36500^2 would be the chance of two such events on a day that had been picked without any foreknowledge that there were going to be any meteor/asteroids: say, if we got two such events on the "Mayan Apocalypse" Day Dec. 12, 2012, that would have been so unlikely we would have to think the Mayan Apocalypse believers were actually on to something. But: given that we already knew this was a day that there was one asteroid flying close by, to have a second similar event on the same day would be 1 out of 36500.
Reply | Report Abuse | Link to thisIf these objects were not on similar paths I think we can rule out any linkage. Even if, hypothetically, a common event somewhere else (such as a collision in the asteroid belt) kicked these objects on two different Earth intercepting orbits, there is exceedingly little probability that they would arrive, following those significantly different paths, at the same time, at the point in space where Earth happens to be. Either they have been in some kind of close proximity for an extended period (orbiting?) or they are truly unrelated.
Reply | Report Abuse | Link to thisForeknowledge of the one event does not change its frequency of occurrence. IMO, the probability that the two events will coincide (presuming 100 year events) would still be 1/36500^2.
Reply | Report Abuse | Link to thisRockyBob - IMO the issue is that the possibility that the two events could be causally related was dismissed out of hand, as I understand based solely on the knowledge that 2012 DA14 was approaching the Earth from the Southern hemisphere and the Russian impactor was observed to enter Earth's atmosphere in the upper latitudes of the Northern hemisphere, apparently headed in a southern direction. I don't think that precludes an Earth approach from the South, since at some point, whatever its orbit had been, it was captured by the Earth's gravitational field. I don't think that the impactor's original orbital path can be sufficiently determined to definitively rule out all potential past interactions with 2012 DA14.
I suspect the quick assessment that the two events were unrelated was intended to allay any fears that other undetected impactors might be on their way (which, of course, could not be completely ruled out). The response is justifiable on social grounds but I think not on scientific grounds.
jtdwyer nailed it when he said:
Reply | Report Abuse | Link to this"I suspect the quick assessment that the two events were unrelated was intended to allay any fears that other undetected impactors might be on their way (which, of course, could not be completely ruled out). The response is justifiable on social grounds but I think not on scientific grounds."
There are many alarmists that were ready to claim, a debris field would cause a meteor shower of apocalyptic proportions, and was about to bring on world catastrophe. Hence, anti-panic, scientific sounding assurances were made, before any real science could have been assessed.
We will learn over the next few days if their guess is correct. As to telling white lies to assure people... I have mixed feelings, on such treatment, of the adult population. I, for one, always prefer, to be armed with real facts. GK
The event that wiped out nearly all life on Earth 65 million years ago was a very unlikely and improbable event but it Did happen.
Reply | Report Abuse | Link to thisJust like a few other such impacts during the time of Life on Earth.
It is a scary thought , but it could happen again , later today.
Why will they always (yes, in 1908 and now in 2013) land in Russia? Why don't they land in India, say in the deserts in Rajasthan or Kutch (not in metropolitan cities like Mumbai or Kolkata, ...)!
Reply | Report Abuse | Link to thisMore specifically, Siberia. The third largest meteorite in the past ~century also hit there:
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Sikhote-Alin_meteorite
“Sikhote-Alin is an iron meteorite that fell in 1947 on the Sikhote-Alin Mountains in eastern Siberia. Though large iron meteorite falls had been witnessed previously and fragments recovered, never before in recorded history had a fall of this magnitude been observed. An estimated 70 tonnes of material survived the fiery passage through the atmosphere and reached the Earth.”
Not suggest causation, but Siberia is the home of the massive basalt flows produced by the Siberian Traps...
Statistically, these may be 50 year events - but only in Siberia! In the rest of the world, they might be, for example, 50,000 year events...
More seriously, though, observed meteorites are more likely to land in, and historical evidence is more likely to be found in, the largest expanse of land mass - Russia.
Russia accounts for over 10% of the world's land area. So if meteor hits land, there's 10% probability it's in Russia.
Reply | Report Abuse | Link to thisJtdwyer: these two celestial events are entirely unrelated to each other. This is merely a coincidence of cosmic proportions.
Reply | Report Abuse | Link to thistimbo555: these celestial events are entirely unrelated to global climate. CO2 emissions on Earth have no influence on extra-terrestrial objects.
People, this is Scientific American's website. Please exhibit some tiny degree of scientific literacy in your posts.
jtdwyer: The near miss of a large asteroid and the devastaing meteorite in Russia are totally unrelated.
Reply | Report Abuse | Link to thistimbo555: Earth's climate has absolutely no influence on extra-terrestrial objects.
This is a scientific website. Please. people, if you cannot demonstrate at least a tiny bit of scientific literacy, kindly keep your opinions to yourselves.
In order to state "The near miss of a large asteroid and the devastaing meteorite in Russia are totally unrelated.", one would have to know the complete trajectory history of the strike as well as the elemental composition and texture of both bodies.
Reply | Report Abuse | Link to thisThis was unknowable at the time that such statements were made. It will take some time to determine such, with any scientific certainty. It not like we were tracking this object during it's travels, before it hit.
And yes, some alarmist people, have proposed that GW causes an expanded atmosphere, which is therefore able to capture slightly more fly-bys, than a cooler planet. GK
"Foreknowledge of the one event does not change its frequency of occurrence. IMO, the probability that the two events will coincide (presuming 100 year events) would still be 1/36500^2."
Reply | Report Abuse | Link to thisWrong. The probability of getting five heads straight in a toss coin is 1/2^5 = 1/32. Now if you got four straight heads, what's the probability you'll get five straight heads? Of course 1/2! Prior knowledge changed the probability.
Another classic example. Three boxes, two empty, one contains a prize. You picked box A. The probability that prize is in box B is 1/3. I opened box C and it's empty. What's the probability that prize is in box B? Of course 2/3!
"Her calculations show that the meteoroid was approximately 15 meters across when it entered the atmosphere, and put its mass at around 40 tons."
Reply | Report Abuse | Link to thisAre you kidding us Margaret? If the meteor was spherical, your estimate will give it a density of 23 kg/m^3. That's lighter than styrofoam. Rock density is about 2,500 kg/m^3. To get that density, the meteor has to be cylindrical 15 m long and 1.2 m diameter. Have you ever seen a meteor that looks like a long thin cylinder? Or maybe other reports that put the mass at 7,000 tons are more sensible.
15 m dia and 40 tonns in weight, seems a little light for me!
Reply | Report Abuse | Link to thisOf course it's also possible it's much smaller than 15 meters and not the largest in a century and therefore quite a common occurrence. Why we don't often see meteor impacts? They usually disintegrate in the air and fall in the ocean (71% probability based on surface area). Vanish without a trace.
Reply | Report Abuse | Link to thisIt won't be the biggest for long--in 2 years or less we may have thousands of even larger meteors to pickup all over the Earth if the Comet C/2013 A1 (Siding Spring) does indeed impact Mars on October 19th, 2014. That Comet is traveling so fast (126,000 mph) and so big (30 miles across) that it will send huge chunks of Mars into the path of all the inner planets including the Earth (as a swarm).
Reply | Report Abuse | Link to thisIf it hits it will be the event of the EON--not just the millenium or century.
It can in fact even end life on Earth as we know it.
It's that big.
It would impact Mars with 20 billion megatons--dwarfing by a factor of 100 the Comet Shoemaker 9 that hit Jupiter in 2005.
That's astounding.
Keep an eye on it at this link:
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2013A1;cad=1;orb=1;cov=0;log=0#orb
Midnight, 10 august 1975, Meyruis, France. In 2 to 3 seconds, an asteroid bounced off the upper atmosphere leaving a huge green luminous gash bright enough to read a newspaper for 15 minutes. The object covered some 5 degrees of the night sky, and was superheated white hot as it spun off into space. There was no noise. It rebounded with an aquired angle of some 5 degrees. My wife and I reported it to the Plymouth planetarium, England, who were unable to identify it. It was therefore VERY big, and I then knew what the term 'grazer' really meant. We were at the time watching the annual display of shooting stars from a camp site.
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