Meteorite Hits Russia

[LaurieAG]

Hi Turtle,

 

Sorry mate, it looks like viewer 'hits'. On the right hand side.

Edited February 17, 2013 by LaurieAG

[Turtle]

Hi Turtle,

 

Here are some excerpts (for scientific purposes only) from the past hour. I have seen over 50 'hits' recorded in that time.

 

What other purpose would they serve? Do you mean I can't make jokes?

 

But seriously, for one I don't find where you are getting that map. Can you better direct me???

 

In the second place I see no mention whatsoever from the sources I trust regarding a "swarm" of meteors. Even should those appear, it's normal in astronomical terms. **** happens.

 

Moreover, if the claim is there's nothing "we" can do about "it", what's the point of raising an alarm? Just wannna see people scurry? What? What is the point of fostering fear? I think it's baseless and irresponsible if not a bit cruel. Good grief. :esmoking:

[LaurieAG]

What other purpose would they serve? Do you mean I can't make jokes?

 

But seriously, for one I don't find where you are getting that map. Can you better direct me???

 

Right hand side of page. You might have to scroll across.

 

If they are tracking viewer 'hits' then they are not very accurate.

[Turtle]

The Latest Worldwide Metero/Meteorite News

Right hand side of page. You might have to scroll across.

 

If they are tracking viewer 'hits' then they are not very accurate.

 

I have scrolled all over and seen no headings "Swarm" on a map as is...erhm...was on your attachments. :shrug:

No matter. Visiting the [presumably] sister page The Latest Worldwide Meteor/Meteorite News I see they are linking now to "verified" reports at major news outlets of fireballs in Cuba & California. Again, it's no matter of concern.

 

More people making reports is sufficient an explanation without resorting to a claim of "unusual" or "increased" activity. I find that source anecdotal and of limited scientific usefullness.

 

While they are relatively few, there are scientifically usefull all-sky cameras looking for fireballs all the time. :cheer:

 

Here's a link to see for yourself. >> All Sky Networks @ NASA

[LaurieAG]

The Latest Worldwide Metero/Meteorite News

 

I have scrolled all over and seen no headings "Swarm" on a map as is...erhm...was on your attachments. :shrug:

No matter. Visiting the [presumably] sister page The Latest Worldwide Meteor/Meteorite News I see they are linking now to "verified" reports at major news outlets of fireballs in Cuba & California. Again, it's no matter of concern.

 

More people making reports is sufficient an explanation without resorting to a claim of "unusual" or "increased" activity. I find that source anecdotal and of limited scientific usefullness.

 

While they are relatively few, there are scientifically usefull all-sky cameras looking for fireballs all the time. :cheer:

 

Here's a link to see for yourself. >> All Sky Networks @ NASA

 

Hi Turtle, thanks for the link.

 

I just talked with my father because I sent him the same link earlier this afternoon and he looked at the google map on the site and saw an entirely different suburb and location to what I saw for the Gold Coast entry. Hmmm.

 

http://bits.blogs.nytimes.com/2013/02/15/facebook-admits-it-was-hacked/?hp

 

A common saying among security experts is that there are now only two types of American companies: Those that have been hacked and those that don’t know they’ve been hacked.

[Turtle]

Hi Turtle, thanks for the link.

 

I just talked with my father because I sent him the same link earlier this afternoon and he looked at the google map on the site and saw an entirely different suburb and location to what I saw for the Gold Coast entry. Hmmm.

 

 

Roger copy. Midnight & I'm off to finish watching a werewolf. :dog:

[Deepwater6]

Heard some reports that divers couldn't find anything below the hole in the lake ice. Anyone else hear the same thing? Could it have been a small piece that exploded/disintergrated just above the spot?

[CraigD]

PS Estimates of the size & mass of the rock have been increased.

Russian Meteor Blast Bigger Than Thought, NASA says

I had an intuition the sights, sounds, and damage we were seeing on video were too great to be accounted for by a 10000 kg, 1.5 m diameter body – I should have run some order-of-magnitude energy calculations before accepting them and marveling at how such a small body could be so spectacular (though the thousand-some Russian folk with faces full of glass likely would chose a different adjective :(). 10000000 kg and 17 m is a more intuitively satisfying estimate.

 

…

The projectile begins to breakup at an altitude of 46200 meters = 152000 ft

The projectile bursts into a cloud of fragments at an altitude of 31500 meters = 103000 ft

…

Peak Overpressure: 47.6 Pa = 0.000476 bars = 0.00676 psi

Max wind velocity: 0.112 m/s = 0.251 mph

Sound Intensity: 34 dB (Easily Heard)

 

All sounds in line with the ground effects in evidence, except the Sound Intensity seems way low. Rather than (Easily Heard) it should output (Impossible to Ignore).

The altitude before breakup looks too high – estimates from observations and calculations, per this wikipedia article, are in the 15000 to 25000 m range. Relatedly, the sound pressures seem too low – my guess from watching the videos is in the 100-140 dB range, with peak overpressure on the order of 5000 Pa. 50 Pa won’t break glass or rock cars. Though it depends on glass thickness, material, tempering and size, 5000 Pa is an engineering handbook rule-of-thumb value for breaking glass, which the Chelyabinsk event did a lot of, including even small panes.

 

Heard some reports that divers couldn't find anything below the hole in the lake ice. Anyone else hear the same thing? Could it have been a small piece that exploded/disintergrated just above the spot?

My guess is that the divers were looking for one of a few large object – not an unreasonable objective on the first few of what I imagine will be a series of many dives or other explorations (lake Chebarkul is fairly shallow, max 12 m, so a lot of options are available, including using caissons to allow open air examination of the lakebed in the vicinity of the hole in the ice) – and didn’t find them. This suggests the meteorite broke into unexpectedly small fragments, which a more thorough search will eventually find.

 

The new estimates force me to reconsider my earlier take on the detectability of this meteor

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.

Were it a radar-reflective surface, like smooth iron, a 17 m diameter target at 30000 m or so altitude strikes me as something that would stand out on Russian radar. As most experts are guessing this meteor was rocky, it may have had such an irregular, even pitted surface, that it was effectively radar stealthy, and been missed by all radar running at the time.

 

Being as how the Russian military is cagey about giving away how good they are or are not at spotting stealth bombers and such, I’d be surprised if much clearly stated info on radar tracks or the lack of them is forthcoming. Hopefully, if they exist, detail trajectory data will be discretely leaked to trustworthy scientists, who can get an obscured form of them into the scientific literature without giving away military secrets.

[Deepwater6]

Always a good thing to have our representatives promoting science at work. However, someone is misinformed about what can/may be detected. Remembering a story of a few years past, I found it out again. Note that the meteroid in question was considerably smaller and less massive than the Russia stone.

 

So the technology is there we just don't give the proper programs enough funds? I thought we put you in charge of watching out for these things T? Were you asleep in the control room again? :0318: No worries when one beans me on the head I'd prefer it be a surprise anyway. :edizzy:

 

>> Meteorites Found in Africa From First Predicted Asteroid Hit

[Turtle]

Always a good thing to have our representatives promoting science at work. However, someone is misinformed about what can/may be detected. Remembering a story of a few years past, I found it out again. Note that the meteroid in question was considerably smaller and less massive than the Russia stone.

 

>> Meteorites Found in Africa From First Predicted Asteroid Hit

.

 

So the technology is there we just don't give the proper programs enough funds?

 

Yes.

 

I thought we put you in charge of watching out for these things T? Were you asleep in the control room again? No worries when one beans me on the head I'd prefer it be a surprise anyway.

 

Yes, y'all put me in charge. Yes, I was sleeping again. You get what you pay for with this ol' turtle by gum!! :lol:

 

As to a meteorite beaning you - or beaning me for that matter- , we should be so lucky. Being ourselves our own property, we would own the rock legally and profit selling pieces of it, not to mention the revenue from appearances, photos of the impact site, suing Italy for not warning us, space-rock energized "appliances" and other such promotions as the mind may conive.

 

I'm awake now and I said dance Alien!!!

[Turtle]

I had an intuition the sights, sounds, and damage we were seeing on video were too great to be accounted for by a 10000 kg, 1.5 m diameter body – I should have run some order-of-magnitude energy calculations before accepting them and marveling at how such a small body could be so spectacular (though the thousand-some Russian folk with faces full of glass likely would chose a different adjective :(). 10000000 kg and 17 m is a more intuitively satisfying estimate.

 

I have been reading how the townfolk are taking some measure of pride in how well they took the blow and that jokes proliferate. e.g. Residents of the meteor were terrified to see Chelyabinsk approaching. :omg: Those Russians!!

 

 

The altitude before breakup looks too high – estimates from observations and calculations, per this wikipedia article, are in the 15000 to 25000 m range. Relatedly, the sound pressures seem too low – my guess from watching the videos is in the 100-140 dB range, with peak overpressure on the order of 5000 Pa. 50 Pa won’t break glass or rock cars. Though it depends on glass thickness, material, tempering and size, 5000 Pa is an engineering handbook rule-of-thumb value for breaking glass, which the Chelyabinsk event did a lot of, including even small panes.

 

Hard to say yet where the "error" lies in that. Once fragments are analyzed we should have a more accurate read on the density. You can look at a PDF of the formulae used for the calculator and compare them to your own. Imapct Program Specifics

 

 

My guess is that the divers were looking for one of a few large object – not an unreasonable objective on the first few of what I imagine will be a series of many dives or other explorations (lake Chebarkul is fairly shallow, max 12 m, so a lot of options are available, including using caissons to allow open air examination of the lakebed in the vicinity of the hole in the ice) – and didn’t find them. This suggests the meteorite broke into unexpectedly small fragments, which a more thorough search will eventually find.

 

Agreed. I would be fishing with a magnet myself. KISS :kiss:

 

The new estimates force me to reconsider my earlier take on the detectability of this meteor

Were it a radar-reflective surface, like smooth iron, a 17 m diameter target at 30000 m or so altitude strikes me as something that would stand out on Russian radar. As most experts are guessing this meteor was rocky, it may have had such an irregular, even pitted surface, that it was effectively radar stealthy, and been missed by all radar running at the time.

 

Being as how the Russian military is cagey about giving away how good they are or are not at spotting stealth bombers and such, I’d be surprised if much clearly stated info on radar tracks or the lack of them is forthcoming. Hopefully, if they exist, detail trajectory data will be discretely leaked to trustworthy scientists, who can get an obscured form of them into the scientific literature without giving away military secrets.

 

Note that the smaller meteor detected and predicted to hit that I referenced in a link a few posts back was detected by optical means; not radar.

 

Finally, just found satellite images of the entry/impact.

 

2 photos here. >> Satellite Sees Russian Meteor Explosion from Space

[CraigD]

Though it notes that most Russians accept scientific explanations for the Chelyabinsk meteor, this CSMonitor article suggest that perhaps 25% of Russians prefer various fringe theories and supernatural explanations.

 

Just a bit of amusing news of the weird.

[Turtle]

Though it notes that most Russians accept scientific explanations for the Chelyabinsk meteor, this CSMonitor article suggest that perhaps 25% of Russians prefer various fringe theories and supernatural explanations.

 

Just a bit of amusing news of the weird.

 

I wager it's as weird -if not weirder- in South Carolina. (That ain't funny. )

 

Anyway, found a bit of news reporting nothing to report yet on the analysis results of recovered fragments. :coffee_n_pc:

 

Report: Injured Russians leave hospital, analysis of meteorite fragments begins @CNN

...

Meanwhile, the first fragment of meteorite arrived in Moscow on Friday for analysis, RIA Novosti reported.

 

About 50 small fragments have been found so far, the news agency reported earlier this week, some in a crater in the Chelyabinsk region's Lake Chebarkul.

 

Images taken soon after the meteor blast showed a hole in the ice covering the lake where a chunk of meteorite was believed to have fallen.

 

Because the meteor exploded in a huge fireball in the atmosphere, the fragments could be scattered over a huge area.

 

A couple of purported pieces of Chelyabinsk meteorite were advertised for sale on the eBay online auction site Friday.

 

...

The whole event, from the meteor's atmospheric entry to its disintegration in the air above central Russia, took 32.5 seconds, NASA said.

...

[LaurieAG]

I found the following article which does a good job of tracking the path.

 

http://ogleearth.com/2013/02/reconstructing-the-chelyabinsk-meteors-path-with-google-earth-youtube-and-high-school-math/comment-page-3/

[Turtle]

I found the following article which does a good job of tracking the path.

 

http://ogleearth.com/2013/02/reconstructing-the-chelyabinsk-meteors-path-with-google-earth-youtube-and-high-school-math/comment-page-3/

tres kewl!!! his calculated angle of entry [red line] looks far steeper than my 15º estimate that i have been using in the impact calculator. however, i don't see where he or others actually give an entry angle. from the above diagram i'm now guessing 45º. ?? more? less? :shrug: give me a consensus and i'll do a run with the angle parameter change and see what happens to those sound & height-of-breakup outputs. :computerkeys:

Edited February 24, 2013 by Turtle

[Deepwater6]

The Science channel has a show at 8pm tonight on this event. The name of the program is "Fire in The Sky."