Author Topic: Meteor Strikes Chelyabinsk, Russia  (Read 140769 times)

Offline ChileVerde

  • Full Member
  • ****
  • Posts: 1176
  • La frontera
  • Liked: 3
  • Likes Given: 0
"I canít tell you which asteroid, but there will be one in 2025," Bolden asserted.

Offline smoliarm

  • Full Member
  • ****
  • Posts: 505
  • Moscow, Russia
  • Liked: 210
  • Likes Given: 69
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #501 on: 03/24/2013 12:13 AM »
to Robotbeat:
This is close to off-topic, so I'll try to be concise.

Your statement
Quote
Clearly, if you have two objects hit or nearly hit within a short timeframe (a day or so) and appear to be completely independent events, then it is much more likely your calculation of the probability was wrong than that you just experienced an event not likely to happen within a trillion times the age of the Universe.
is incorrect, it violates fundamental principle of probability theory: single event does not provide any basis to estimate its probability.

Unfortunately, I can refer you to textbooks in Russian, I never got to teach such basic course in English. (I used to teach advanced statistics in application to analytical chemistry, but it's grad level).
Your follow-up posts are basically attempts to built a kind of statistical 'Perpetuum mobile'. It won't work, take my word :)

MOREOVER, there are two more reasons this dispute has no sense.
FIRST: modern models for estimation of catastrophic impact probability are fairly unreliable, nobody argues against that. May be crap is better word.
SECOND: Even if you get the right probability number - how are you going to convince public,media, congress et al., that they need to spend money on appropriate early warning system ?

Finally, to the topic -- I strongly hope that this double event - DA14 and Chebarkul - WILL help B612 with their Sentinel project.


Offline deltaV

  • Full Member
  • ****
  • Posts: 1538
  • Change in velocity
  • Liked: 165
  • Likes Given: 480
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #502 on: 03/24/2013 03:06 AM »
Those two NEO events are two additional data points that may factor into our estimates of NEO probabilities, but:
* Our response to them should be identical to how we'd react if they'd happened months apart.
* Our estimates probably won't change much since these events aren't unexpected.

Offline Robotbeat

  • Senior Member
  • *****
  • Posts: 27033
  • Minnesota
  • Liked: 6927
  • Likes Given: 4886
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #503 on: 03/24/2013 03:56 AM »
smoliarm:
Except if you are dealing with a very small number of samples (or essentially none, as in the case of large asteroid impacts that have been observed with cameras), then yeah, one or two additional samples could have a significant effect. In this case it doesn't because we've been tracking thousands of asteroids.

But you are apparently misreading my point. In reality our models are good enough that these two events make essentially no impact on our probability estimates. I never said that they did. I only disagreed with the notion that "under no circumstances could just these two events have any impact (heh) on our probability estimates." Because, yeah, there are some circumstances where just two events could possibly affect our estimates. Just not our current circumstances.

And yeah, I agree the situation is the same as if they had happened months apart.

Ask yourself whether finding independently evolved life on another nearby planet would affect our estimates of the Drake equation, for instance... (Of course they would because our current estimates of the Drake equation are wildly spread over several orders of magnitude... Adding a second data point would tremendously improve our estimates.)
« Last Edit: 03/24/2013 04:03 AM by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Targeteer

  • Senior Member
  • *****
  • Posts: 3624
  • near hangar 18
  • Liked: 802
  • Likes Given: 388
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #504 on: 03/28/2013 12:59 PM »
For those in the US, PBS' NOVA program on 27 Mar will cover the search for fragments.

Just watched the program on the DVR.  Interesting and detailed.  The object was mostly rock (90%) and orbitology showed that the earth actually ran down the object from behind.  The largest fragment shown was slightly smaller that a baseball.
Best quote heard during an inspection, "I was unaware that I was the only one who was aware."

Offline Moe Grills

  • Full Member
  • ****
  • Posts: 780
  • Liked: 25
  • Likes Given: 1
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #505 on: 03/28/2013 08:34 PM »
Clearly, if you have two objects hit or nearly hit within a short timeframe (a day or so) and appear to be completely independent events, then it is much more likely your calculation of the probability was wrong than that you just experienced an event not likely to happen within a trillion times the age of the Universe.

No, sorry, this is wrong. This would be a single event and would have
In these circumstances of a close pass and a collision, they don't effect current models because the models already say that close-passes are relatively common and large hits can happen between once a decade and once a century.

I have to shake my head in disgust at the abstract impersonal debate
developing.
  Do all of you realize that that meteoroid/asteroid HAD a major orbital axis
that once stretched well over 200 million klicks before it slammed into our atmosphere? And it released most of its energy 30 klicks above a major Russian city?
Compare 30 klicks to over 200 million klicks.
In other words? If it had exploded with over 400 kilotons of energy released, 10 kilometers closer to earth, the shockwave over-pressure would have KILLED THOUSANDS of human beings like you and me.

Online aero

  • Senior Member
  • *****
  • Posts: 2785
  • 92129
  • Liked: 724
  • Likes Given: 249
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #506 on: 03/28/2013 09:28 PM »
From Wikipedia
Quote
Chelyabinsk Meteor 17 to 20 metres across

If the meteor had struck more centrally, more of a direct hit than it did, then it may well have penetrated lower into the atmosphere before exploding.

Our NEO detection methods don't begin to catalog these small objects and they only strike every few generations so I guess everyone we know now is probably safe from them. But some areas have a higher population density than Chelyabinsk and population density is generally increasing, so how soon will it be before the risk from these small asteroids becomes worrisome?

Retired, working interesting problems

Offline rickl

  • Full Member
  • ****
  • Posts: 853
  • Pennsylvania, USA
  • Liked: 97
  • Likes Given: 125
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #507 on: 03/28/2013 10:56 PM »
For those in the US, PBS' NOVA program on 27 Mar will cover the search for fragments.

Just watched the program on the DVR.  Interesting and detailed.  The object was mostly rock (90%) and orbitology showed that the earth actually ran down the object from behind.  The largest fragment shown was slightly smaller that a baseball.

I just watched it online.  Very good documentary.  Here's the link:

http://video.pbs.org/video/2358778286
Nominal now means "Yeehah!!"

Offline AndrewSTS

  • Member
  • Full Member
  • ****
  • Posts: 697
  • New York
  • Liked: 1
  • Likes Given: 6
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #508 on: 03/29/2013 08:29 PM »
That was very interesting, thanks!

Offline kevin-rf

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8526
  • Overlooking the path Mary's little Lamb took..
  • Liked: 1028
  • Likes Given: 235
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #509 on: 03/31/2013 10:56 PM »
Thanks, it gave me a reason to turn on the TV!
If you're happy and you know it,
It's your med's!

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3745
  • Earth
  • Liked: 146
  • Likes Given: 3040
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #510 on: 04/23/2013 04:13 AM »
http://www.thespacereview.com/article/2277/1

New article from Jeff. 

Spoiler alert: 




sunburns/burnt peeling skin on local. 
« Last Edit: 04/23/2013 04:15 AM by go4mars »
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3745
  • Earth
  • Liked: 146
  • Likes Given: 3040
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #511 on: 05/14/2013 03:35 AM »
there is no case in the entire recorded history of meteorite tsunami.
Does Burckle crater not count?
Of course, it does not  :)
I am talking about historical records and about events

Exodus 14:19-29 "pillar of cloud", water recedes, rushes back ... hey who knows?
http://www.lpi.usra.edu/meetings/lpsc2009/pdf/2243.pdf
It seems strange to me that no one has sent a boat out there for some samples.  Burckle crater, if characterized better, could have some really signifcant implications for many fields, archeology being a biggy. 

In concert with stuff like this:  http://forum.nasaspaceflight.com/index.php?topic=31118.msg1022991#msg1022991

There could be a re-think on frequency of larger events, damage potential of larger bollides, a careful look at certain orbits, and an acceleration of our tracking capability for "hazards" that are 15 meters or less.   

If I had less responsibilities, I'd strongly consider doing a PhD on this subject.  Maybe when I'm an empty-nester.           It might fit in well with retirement ambitions of field work on Mars.   
« Last Edit: 05/14/2013 03:42 AM by go4mars »
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline iamlucky13

  • Full Member
  • ****
  • Posts: 1660
  • Liked: 102
  • Likes Given: 93
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #512 on: 05/17/2013 03:46 AM »
sunburns/burnt peeling skin on local. 

I've not read of any related claims.

But it looked like a mostly clear day, and even the winter sun can still potentially cause a nasty burn if you're pasty white from staying inside all winter, and then spend several hours staring up at the dissipating smoke trail and wondering at what happened.

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3745
  • Earth
  • Liked: 146
  • Likes Given: 3040
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #513 on: 05/27/2013 03:13 AM »
I'm not aware of any threads specifically for the Holocene/Younger Dryas impact ideas.  I assume people interested in that would probably click on this thread.  The comment section for this article has a lot of interesting thoughts related to fairly large, fairly recent impacts (regionally catastrophic):

http://wattsupwiththat.com/2013/05/24/where-lies-the-younger-dryas-smoking-gun/#more-86924

like this link:
http://cometstorm.wordpress.com/2011/04/27/a-different-kind-of-climate-catastrophe-2/
« Last Edit: 05/27/2013 03:15 AM by go4mars »
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline JohnFornaro

  • Not an expert
  • Senior Member
  • *****
  • Posts: 9162
  • Delta-t is the salient metric.
  • Planet Eaarth
    • Design / Program Associates
  • Liked: 610
  • Likes Given: 314
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #514 on: 05/31/2013 01:46 PM »
Thanks for the learn something new every day moment with the link to WUWT.
Sometimes I just flat out don't get it.

Offline Targeteer

  • Senior Member
  • *****
  • Posts: 3624
  • near hangar 18
  • Liked: 802
  • Likes Given: 388
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #515 on: 08/27/2013 06:40 AM »
The meteor showed heating from some previous encounter(s) before finally meeting it's end.

http://news.yahoo.com/russian-meteor-explosion-space-rock-had-near-misses-222044770.html
Best quote heard during an inspection, "I was unaware that I was the only one who was aware."

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3745
  • Earth
  • Liked: 146
  • Likes Given: 3040
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #516 on: 08/27/2013 01:49 PM »
Interesting article.  I suspect the author was a little confused about the mechanism for increased concentration of platinum group metals in the fusion crust.  It isn't called a fusion crust because of nuclear fusion!! 
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline kevin-rf

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8526
  • Overlooking the path Mary's little Lamb took..
  • Liked: 1028
  • Likes Given: 235
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #517 on: 08/27/2013 03:13 PM »
It isn't called a fusion crust because of nuclear fusion!! 
IF the earlier melt was from getting to close to the sun, technically...

Very, Very interesting none the less.

Btw. Where in the article do you seem them mentioning nuclear fusion? I just re-read it three times and don't see it.
Quote
"We think the appearance (formation) of this platinum group mineral in the fusion crust may be linked to compositional changes in metal-sulfide liquid during remelting and oxidation processes as the meteorite came into contact with atmospheric oxygen."
« Last Edit: 08/27/2013 03:18 PM by kevin-rf »
If you're happy and you know it,
It's your med's!

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3745
  • Earth
  • Liked: 146
  • Likes Given: 3040
Re: Meteor Strikes Chelyabinsk, Russia
« Reply #518 on: 08/27/2013 08:12 PM »
Where in the article do you seem them mentioning nuclear fusion? I just re-read it three times and don't see it.

Unless the article changed, I must have read it too fast.  You're right.  Maybe I thought the implication was elements that formed on entry (because he mentions elements of the alloy as opposed to a mineral name or something).  No concentrations given. 

Quote
Another surprise finding from the Chelyabinsk meteorites came from their fusion crusts. There, researchers found small amounts of platinum-group elements, in the form of an alloy of osmium, iridium and platinum, that are rare in this layer of meteorites. The scientists think these may have formed when the falling rocks slam into Earth's atmosphere.
  He switches from "an alloy" to the word "these".  Does these mean "these elements"?  Or "these alloys".  Maybe that was where the horse bucked me. 

In a fluidized hot sand bed, where coke rinds on grains are burned, nickel and vanadium are left as a deposit on the grains in a process like this:
http://www.ivanhoeenergy.com/index.php?page=htl_process_overview

I wonder if that's analogous. 
« Last Edit: 08/27/2013 08:15 PM by go4mars »
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline Targeteer

  • Senior Member
  • *****
  • Posts: 3624
  • near hangar 18
  • Liked: 802
  • Likes Given: 388
Best quote heard during an inspection, "I was unaware that I was the only one who was aware."

Tags: