Meteorite Hits Russia

[Moontanman]

A ten ton meteorite hit Russia this morning or late last night, reports suggest the meteorite hit the outskirts of Moscow. ABC News video of the impact...

 

http://www.youtube.com/watch?v=bH136SW4q78

 

We are lucky it didn't make them think it was nuclear attack, if this had happened during the cold war the flash of the meteorite hitting might have been mistaken for a nuclear attack and with all those missiles on high alert could have been a very very bad thing...

[CraigD]

Wow.

Judging from the many Russian audio/video recording of it (lots of folk have camcorders of some sort these days), people appear to have concluded early on that it was what it was – a meteor, not an aircraft, missile, or bomb. This Slate article by Phil Plait has a good collection of videos, showing both the meteor’s trail, its huge sonic boom, building damage and people’s reactions. He seems to have gotten most of his videos from this Russian language LiveJournal page, by blogger Ilya Varlamov.

It’s very early for them, but estimates are putting the main meteor’s mass at about 10,000 kg, which assuming a generic, rock-like density, would give it a diameter of around 1.5 m. My guess is it wasn’t noticed on any civilian or military radar until after people noticed it by its smoky trail, its light and its sonic boom.

The immediate question to my mind is if this meteor is alone, or part of a spread-out swarm? Expert opinion on a connection between it and 2012 DA14 is contradictory, with some noting that last night’s Chelyabinsk meteor appears to be coming from the wrong direction (East to West, rather than South to North), suggesting it wasn’t traveling with 2012 DA14, and others that find the two events too close in time to be easily explained as coincidental.

It’s interesting that, in all the video’s Plait watched, the powerful boom appears to be a sonic boom, not from the meteor’s midair explosion, which is estimate to have occurred at about 10,000 m altitude, roughly over the city of Chelyabinsk (population about 1,130,000). The only thing that seems to mark the airburst is that the meteors trail abruptly stops – becomes invisible to the naked eye and/or various ordinary cams. http://www.physicsforums.com

[blamski]

i was wondering as well why so much of this was caught on cameras from inside peoples' cars. and also why so much first person perspective of car crashes in russia was all over youtube. apparently the vast majority of russians film while they drive as verbal evidence doesn't hold up too well in russian courts in the event of an incident, and because there is just so much crazy stuff that goes on on russian roads. its kind of an insurance policy in itself.

 

the effects of the sonic boom up to a minute after the thing has passed over though are incredible.

[CraigD]

i was wondering as well why so much of this was caught on cameras from inside peoples' cars

It happened at about 9:15 AM local time. A lot of people were driving to or from work or school.

 

The first video in Phil Plait's article appears to be from the dash cam of a car. At first, I assumed it must be from a police car, but just heard that thousands of Russians have these because they fear police harassment. Notice in that video that the timestamp on the recording isn't set correctly - what one would expect from a private citizen who bought and installed, but doesn't pay much attention to, the cam.

 

. There are a lot of videos from people on rooftops, yards, and streets, too.

[Deepwater6]

I thought the same thing Craig, is that all of it? I would think the powers that be are trying to backtrack it's path to check. At least I hope they are.

 

Little else can done aside from evacuating projected impact zones if there is more. This should help free up some government funds for space. For sure if something hits inside the US wouldn't you think? :rolleyes:

[Deepwater6]

http://www.bbc.co.uk/news/world-europe-21475858

 

BBC news under the science tab had these photos to show some of the damage done.

[CraigD]

I thought the same thing Craig, is that all of it? I would think the powers that be are trying to backtrack it's path to check. At least I hope they are.

I’m not sure how the powers that be are reacting. This Washington Post article quotes Russian Parliament member Vladimir Zhirinovsky, making the sill claim that the event was actual a US weapons test. I imagine he’s not pushing for any optical or radar scans of space for more meteoroids like last night’s.

 

Assuming that many more sensible leaders are directing academic and state managed astronomers, I’m not sure how much can be done to detect more meteoroids like this one. It appears to have been a small one – I estimated about 1.5 m diameter, while the news has been quoting “about kitchen table size” – and likely of unspectacular albedo, so I doubt an optical survey of the sky to the East relative to Chelyabinsk at 0315 GMT would be able to see another. A concerted radar watch in many directions with big dishes like the ones watching 2012 DA14 should be able to, but there aren’t that many such dishes, and several of them are dedicated for a while to watching 2012 DA14.

 

One of the best detectors of small meteors is watching for their trails from space. I’ve not read that the ISS or other orbital observatories have noticed anything out of the ordinary, so assume we’re not seeing the Leonid shower-like increase in meteor burn-ups I’d expect if the Chelyabinsk rock was part of a swarm of various smallish size meteoroids. Of course, by the time you see the streak, there’s not much time for warnings, and not even a precise estimate of where or what its effect will be.

 

Recent news is of 3 confirmed and several other likely impact site downrange of the airburst, so we can start using the term meteorites. Though they were detected by seismometers, and would have been deadly to anyone unlucky enough to actually be hit or very near, they appear to have all been harmless, unlike the pre-airburst sonic boom. Last I read, about 1000 Chelyabinskians (?) have been injured, most by flying glass.

 

Little else can done aside from evacuating projected impact zones if there is more.

I think the best that can be done if another like the Chelyabinsk rock is spotted is to close window coverings and get away from windows or fragile roofs and masonry – pretty much the same precautions as for a tornado. I expect evacuation would be more dangerous than what might come of staying put.

 

This should help free up some government funds for space. For sure if something hits inside the US wouldn't you think? :rolleyes:

I can’t see that this can hurt the cases of folk asking for more money to watch the skys, and be able to do something if a big, really dangerous body is found headed our way.

 

Scientifically and engineering-wise, I’m not sure much can be done about events like this beyond building safety improvements that serve also to protect against the much more likely event of tornados and other major wind storm – and, regrettably, human-caused dangers such as car bombs. But if the story can be spun to increase interest in and funding for astronomy as spaceflight, I’m for it, even if the science gets distorted by the hype. :thumbs_up

[Aethelwulf]

These ''sister meteorites'' probably ejected from the same mass source as the relatively large asteroid which is passing by us today. We are not out of danger yet. Obviously we didn't detect these smaller siblings, there could be more on the way.

[Aethelwulf]

I’m not sure how the powers that be are reacting. This Washington Post article quotes Russian Parliament member Vladimir Zhirinovsky, making the sill claim that the event was actual a US weapons test. I imagine he’s not pushing for any optical or radar scans of space for more meteoroids like last night’s.

 

 

 

The Russian propaganda is outstanding... not that any reasonable advanced country would believe such a claim.

[CraigD]

These ''sister meteorites'' probably ejected from the same mass source as the relatively large asteroid which is passing by us today.

This reasonable explanation of 2 unusual events happening so close to one another in time is confounded by the position and velocity of observed for the Chelyabinsk meteor and 2012 DA14:

• The Chelyabinsk meteor was seen moving east-to-west at about 0915 local time (so it was moving roughly from the direction of the Sun in the plane of the Solar System) at about 15000 m/s (only about 500 m/s of east-to-west motion can be attributed to the Earth’s rotation).
  
• 2012 DA14 has been precisely measured to be moving south-to-north at a speed of about 12700 m/s.
  

From their similar speeds, it’s not unreasonable to guess that these two bodies have/had similar orbital radii (semi-major axes) and eccentricities, but they don’t appear to be anywhere near one another’s planes. A Chelyabinsk meteor-size body preceding 2012 DA14 in the same orbit as it would most likely strike in the Southern Hemisphere, and even if it luckily swept around from the south to north to reach the Russia in the Northern Hemisphere, should be moving south-to-north. Nothing in basic mechanics of the long history of meteor physics can explain such a fast-moving body changing direction by about 90 in a way that would account for what was observed at Chelyabinsk having come from the same orbit as 2012 DA14.

 

We are not out of danger yet. Obviously we didn't detect these smaller siblings, there could be more on the way.

I agree.

 

What this goes to show is that even small, astronomically and ecologically insignificant bodies can cause a lot of property damage and human injury (Fortunately, it appears that few if any people were killed).

 

We can only hope the Chelyabinsk meteor was a singular freak event. If they start happening regularly, at the very least, engineers and insurance companies are in for some challenges.

 

The Russian propaganda is outstanding... not that any reasonable advanced country would believe such a claim.

We in America have got some prominent oddballs in the US, too – folk like John Buchanan, who has publically supported the contention that the World Trade Center towers were not destroyed on 11 Sep 2001 by the hijacked airliners that were clearly seen striking them, but by explosives planted by secret agents of the US government or some super-secret organization.

 

To our nation’s credit, I think, unlike Russia’s Zhirinovsky, Buchanan has never been elected to public office. If were political advantage to be gained from it, though, I don’t doubt that many US politicians would make a claim as silly as Zhirinovsky’s.

[Aethelwulf]

The calm after the storm needs to be recognized as well... easily meteorites could be following the tail of this more massive construction. Also, this is a wakeup call that we cannot detect all space bodies, no matter how advanced our radar detection system is. This is actually quite scary. we are more primitive than what we considered... if things can enter our atmosphere without detection, then there is a serious issue of national defense involved.

[Eclogite]

The calm after the storm needs to be recognized as well... easily meteorites could be following the tail of this more massive construction. Also, this is a wakeup call that we cannot detect all space bodies, no matter how advanced our radar detection system is. This is actually quite scary. we are more primitive than what we considered... if things can enter our atmosphere without detection, then there is a serious issue of national defense involved.

I disagree completely. It is well understood that bodies of this size cannot, practically, be detected. Because their potential for causing damage is relatively minor they do not represent a significant threat.

 

Let me anticipate someone saying, but what if it had hit in the middle of a major city? The odds are very much against that and even so the death toll would be considerably less than the annual death toll from car accidents in any reasonably sized country on the planet.

 

In short, this was an interesting event, with unfortunate consequences for a few people. Within the next fifty years the chances are a larger and still undetectable event will cause loss of life and that will still be of relative unimportance. It's the sizable objects like the one that made Meteor Crater in Arizona, and a little smaller, that we need to be concerned about.

[Moontanman]

has a large meteor ever been observed striking the moon?

[Aethelwulf]

Hi moon... I am going to be a bit handwavey because I don't know the true answer to that question... but there are some hints. I remember an astronomer saw ''flashes of light'' on the moon. Many Ufologists today like to attribute it to... well you know. However, even though I am pro-UFO, it is likely he saw rocks hitting the surface with an impact capable of causing devastating radiation.

[Moontanman]

Hi moon... I am going to be a bit handwavey because I don't know the true answer to that question... but there are some hints. I remember an astronomer saw ''flashes of light'' on the moon. Many Ufologists today like to attribute it to... well you know. However, even though I am pro-UFO, it is likely he saw rocks hitting the surface with an impact capable of causing devastating radiation.

 

 

The original estimate of the meteors size has been upgraded from 1.5 meters to 15 meters, I was thinking about how much damage such a metro would cause of it hadn't been intercepted by the atmosphere... I would think much of the debris would escape the moons gravity and fall to the earth. I wonder if anyone has calculated how big a meteor would have to be and hit the moon and endanger the earth with it's debris...

[Eclogite]

has a large meteor ever been observed striking the moon?

Yes. For example.

 

The original estimate of the meteors size has been upgraded from 1.5 meters to 15 meters, I was thinking about how much damage such a metro would cause of it hadn't been intercepted by the atmosphere

That is a substantial upgrade! Taking the new diameter and assuming a 13 km/sec impact velocity, with a chondritic composition and density gives a yield of 130 kilotons. There's an online calculator somewhere that will do the same calculation. If you find it and get a different answer let me know - I think I've got my unit conversions and decimals in the right place, but I've never double checked my own Excel calculator. Incidentally if it was an iron (which I doubt) the energy yield would be double.

[Buffy]

Here's a picture of the crater (in an ice covered lake) from one of the fragments that landed:

 

 

See more pics here: Talking Points Memo Russia Meteorite

 

Nice collection of videos: Talking Points Memo: 9 Spectacular Videos

 

The ships hung in the sky in much the same way that bricks don't, :phones:

Buffy