[meteorite-list] POP QUIZ FRIDAYS ANSWER AND WINNER OF THE ORNANSMETEORITE

From: John.L.Cabassi <John_at_meteoritecentral.com>
Date: Wed, 18 Jan 2012 18:31:49 -0800
Message-ID: <4E64E23CEBA94DE193016807AEEC6549_at_anitak9bz49jy2>

G'Day Shawn
Now that was a definite curve ball and a misunderstanding on my behalf. Your question was "How many meteorite falls are there with accurate tracking data on atmospheric passage?" I think the key words are "meteorite" and "falls". Correct me if I'm wrong. I found Almahata Sitta is one of the most accurate recorded falls of all time.

I also see "interplanetary meteoroids and small asteroids" of your suggested reading.

My question to you, regardless of the contest which I appreciate your generosity and my continued education; we have a conflict with meteoroids and meteorites. I'm interested to know in what you have posted, what meteorite falls make up this 13?

Can you elaborate on their names of what actually hit the ground as a meteorite? Just curious. An over-active mind

Cheers
John Cabassi
IMCA # 2125

-----Original Message-----
From: meteorite-list-bounces at meteoritecentral.com [mailto:meteorite-list-bounces at meteoritecentral.com] On Behalf Of Shawn Alan
Sent: Wednesday, January 18, 2012 4:51 PM
To: Meteorite Central
Subject: [meteorite-list] POP QUIZ FRIDAYS ANSWER AND WINNER OF THE ORNANSMETEORITE


Hello Listers

Sorry for the delay been busy with other projects. I would like to give a shout out to the Mars meteorite and the finalized name :) cool stuff, cant wait to read about it in my MAPS. If people do not know what I am talking about go to http://www.meteoriticalsociety.org/ an join the CLUB it worth every penny.

Now back to the QUIZ

I would like to say thank you Listers for sending in your answer :)

Question

How many meteorite falls are there with accurate tracking
data
on atmospheric passage?

Answer

13

If you like to read up on this keep on reading...........


Very low strengths of interplanetary meteoroids and small asteroids

 1. Olga POPOVA1,*,
    2. Ji?? BOROVI?KA2,
    3. William K. HARTMANN3,
    4. Pavel SPURN?2,
    5. Edwin GNOS4,
    6. Ivan NEMTCHINOV1,?,
    7. Josep M. TRIGO-RODR?GUEZ5

Article first published online: 29 SEP 2011
DOI: 10.1111/j.1945-5100.2011.01247.x
? The Meteoritical Society, 2011
Issue

Meteoritics & Planetary Science
Volume 46, Issue
10, pages 1525?1550, October 2011


Abstract? We have assembled data on 13 cases of meteorite falls with
accurate tracking data on atmospheric passage. In all cases, we estimate the
bulk strength of the object corresponding to its earliest observed or inferred
fragmentation in the high atmosphere, and can compare these values with measured
strengths of meteorites in the taxonomic class for that fall. In all 13 cases,
the strength corresponding to earliest observed or inferred fragmentation is
much less than the compressive or tensile strength reported for that class of
stony meteorites. Bulk strengths upon atmospheric entry of these bodies are
shown to be very low, 0.1 to approximately 1 MPa on first breakup, and maximal
strength on breakup as 1?10 MPa corresponding to weak and ?crumbly? objects,
whereas measured average tensile strength of the similar meteorite classes is
about 30 MPa. We find a more random relation between bulk sample strength and
sample mass than is suggested by a commonly used empirical power law. We
estimate bulk strengths on entry being characteristically of the order of
10?1?10?2 times the tensile strengths of recovered
samples. We conclude that pre-entry, meter-scale interplanetary meteoroids are
typically highly fractured or in some cases rubbly in texture, presumably as a
result of their parent bodies? collisional history, and can break up under
stresses of a few megapascals. The weakness of some carbonaceous objects may
result from very porous primordial accretional structures, more than fractures.
These conclusions have implications for future asteroid missions, sample
extraction, and asteroid hazard mitigation.

source: http://onlinelibrary.wiley.com/doi/10.1111/j.1945-5100.2011.01247.x/abstract

I would like to congratulate Brett W for being the first to submit the correct answer because there was on 7th Lister that got the answer right. He will be getting a free Ornans 5mg fragment.

Till next time keep on rocking

Shawn Alan
IMCA 1633
eBay Store
http://www.ebay.com/sch/ph0t0phl0w/m.html?
______________________________________________
HAPPY HOLIDAYS!!
Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html
Meteorite-list mailing list
Meteorite-list at meteoritecentral.com
http://six.pairlist.net/mailman/listinfo/meteorite-list
Received on Wed 18 Jan 2012 09:31:49 PM PST