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Huge Meteor Blazes Across Sky Over Russia; Hundreds Injured
New submitter dovf writes "The Bad Astronomer analyzes incoming reports about the apparent meteoric fireball over Russia: 'Apparently, at about 09:30 local time, a very big meteor burned up over Chelyabinsk, a city in Russia just east of the Ural mountains, and about 1500 kilometers east of Moscow. The fireball was incredibly bright, rivaling the Sun! There was a pretty big sonic boom from the fireball, which set off car alarms and shattered windows. I'm seeing some reports of many people injured (by shattered glass blown out by the shock wave). I'm also seeing reports that some pieces have fallen to the ground, but again as I write this those are unconfirmed." This is the best summary I've found so far, and links to lots of videos and images. He also clarifies something I've been wondering about: 'This is almost certainly unrelated to the asteroid 2012 DA14 that will pass on Friday.'"
As of right now, English-language sources seem to be a bit behind on the injury/damage reports.
The current reports from the city government say that 725 people have received medical attention, with 31 being hospitalized. Infrastructural damage amounts to problems in the centralized building heating system, and blown out windows in about 3000 apartment buildings, 34 hospitals and clinics, and 361 schools/daycares. I should note that, this being Russia, blown out windows are a serious matter because they render the buildings cold, especially coupled with heating system problems. Gas supply has been turned off in parts of the city as a precaution.
Overall, though, there appears to be no serious damage - though emergency repairs and lots of new windows are needed.
Dashcams are apparently because their courts are such that they need that kind of evidence if someone hits them.
The fact that they occasionally catch cool videos of other things going on is a bonus. For instance, the crew-only Aeroflot flight back in December that overshot the runway and ran over the fence into a highway. The guy with the camera had to swerve to dodge a passenger seat that bounced in front of him.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
The meteorite was several times larger than the last (and first ever) predicted impact in 2008.
It is trivially possible these days, to do several complete surveys of the sky each day and ensure that such asteroids are discovered several days ahead of time. Computers allow us do evaluate the data more or less in real time. The problem is: You need funding for the telescopes around the world and staff to run them.
While all the observatories would do, is to give warning to people in the area to stay indoors and away from windows - or leave the area alltogether if the rock is a bit larger - that's still better than "oups" and a couple videos from dashboard cameras. It would also provide a viable basis for sending up a rocket with a few tons of mass to break up an asteroid into harmless chunks. Possibly a combination of high and low density materials, like concrete and lead, to achieve a good distribution of the momentum through the whole asteroid.
I'm not kidding. A single ton mass in a head-on collision with 10-15km/s has as much kinetic energy as 15-30 tons of high explosives. Which should be enough to break up a 30m asteroid into very small chunks (this one in russia was probably around 10m), although some preparation is certainly in order.
http://www.flickr.com/photos/eumetsat/8474853633/
"An image from the SEVIRI instrument aboard our Meteosat-10 geostationary satellite. The vapour trail left by the meteor that was seen near Chelyabinsk in Russia on 15th February 2013 is visible in the centre of the image."
www.rdex.net
According to TFA , DA14 is approaching from Earth's South while the videos so far make it look like this one is coming from the East, so they're on completely different orbits.
The apparent crash site (or maybe one of several, not clear if there were several sizeable fragments) is in a nearby lake, creating a 6 meter hole in ice. Picture at a news site. The site is under control of Russian authorities and a scientific group is due to arrive tomorrow to study the meteorite.
>TFA
link?
Yep, just click it.
Thank you, Edward Snowden.
"Arguments from authority are worthless." —Carl Sagan
Actually, meteors hitting the earth's atmosphere is a very common event. It happens almost every night. The only difference is that this time the meteor was large enough to be visible and have this result. The big 45m piece of asteroid passing by isn't that uncommon either, it's just passing by relatively close compared to other asteroids.
In short: we're not talking about two uncommon events (certainly not "very rare"). You're falling for the Texas Sharpshooter Fallacy here.
Actually dashcams are a requirement of insurance companies to insure a car.
I can't believe I'm having to explain this, but "TFA" is "The Fucking Article." The link you're looking for is already in the summary.
Meteors like this are a lot smaller than the near-misses that end up in the news. Being able to find, track and see where smaller meteors that result in fireballs but don't reach the ground with any significant force (or at all) is much harder. It was done recently for one that fell over Africa, and that was treated as a big deal as it was by far the smallest one tracked and the first tracked before it hit. But that is more the exception than the rule at the moment for rather small ones. Additionally, predicting where it will go once it hits the air is much more difficult than tracking it in space (not impossible... but does result in some large landing ellipses for shallow angle ones with unknown shapes).
We see posts about twice a year talking about the next "near miss" we're going to have. So what happened with this one? Didn't they catch it? Or did they catch it, realize it was going to hit, and decide not to tell anybody? It
We don't spot 'em all. We've got several active asteroid search programs going, which have discovered thousands of near-earth asteroids, but there are many thousands more. One of the triumphs of 21st-century science is that we now know where almost all of the "end of the world" and "destroy a large country" km-sized near-earth asteroids are. But we think we've only found about half of the "annihilate a city" 300-m sized ones, and most of the mere "hydrogen-bomb" 100-m sized ones remain unknown. This meteor was *much* smaller than that -- I'd guess only a couple meters across. There are probably *millions* of those out there, and they're too small to see at all unless they make a close pass of the EArth.
http://www.nasa.gov/mission_pages/WISE/multimedia/gallery/neowise/pia14734.html
http://www.purdue.edu/impactearth/
You do realize you are speaking of a rock roughly the size of a large van or small delivery truck travelling in space at extreme speeds that once they hit the atmosphere are hypersonic speeds. There aren't any designated travel lanes to look out for in space, and tryin to spot a rock the size of a truck in a 360 degree spherical space of infinite size is a lot harder than finding a sewing needle in a haystack. So, you know it'd be really freaking amazing if they actually did know about this.
On another note Independence day was about an Alien invasion. I think you might be thinking along the lines of the Armegeddon film and it's ilk. There are many issues with blow it up into littler pieces. But that idea is mostly bad for a rock of any considerable size. This meteorite is estimated to be only a few meters in size, maybe 10 tons. The football field size DA14 headed for a "safe" flyby (I'm still waiting to see if it happens to hits a satellite or two on it's way by), would produce hundreds or maybe thousands of rocks this size. While they would be unlikely to do much "surface" damage, if it passed over any metropolitan area you could probably expecte 10s or 100s of thousands injuries and possibly some fatalities and 10s to 100s of millions in property damage.
A better course is to shove to a different trajectory. Like a game of billiards. Although, I'm not happy about that idea much either. Too many variables on unwanted side affects.
Well how's a interceptor missile supposed to know the difference?
Velocity. An ICBM arrives at about 5-7 km/s. An asteroid arrives at a *minimum* of 11 km/s.
why should it even care?
Lots of reasons. Among them: asteroids as big as an ICBM enter Earth's atmosphere several times a year. If you tried to shoot them all down, you'd run out of missiles and money pretty quick. Also, if there's a miscommunication between someone's space program and someone's missile defense program, you end up killing a lot of astronauts.
In practice, any radar that can detect an incoming ICBM comes with enough computer power to instantaneously compute an orbital trajectory for it, and see immediately whether it's an asteroid, a spacecraft, or a suborbital missile.
That's Earth's escape velocity. If you fall into Earth's gravity well from outside, you'll be going at least that fast when you hit the Earth.