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buzzlightbeer
2005-Aug-22, 05:59 PM
i believe some1 else posted a note about this already...but i couldnt find original thread...so here is another posting regarding this startling discovery.

A U of T scientist has found unexpectedly ‘young’ material in meteorites – a discovery that breaks open current theory on the earliest events of the solar system.

University of Toronto press release (http://www.news.utoronto.ca/bin6/050818-1567.asp)

cran
2005-Aug-22, 06:22 PM
Actually Buzz, I think it reinforces current thinking about planetary formation... the "current theory" described in the article
The evolution of the solar system has traditionally been seen as a linear process, through which gases around the early sun gradually cooled to form small particles that eventually clumped into asteroids and planets. hasn&#39;t been current for at least a decade, as far as I am aware... :huh: &#39;traditional&#39; yes, but surely not current? <_<

Once begun, the growth phase of planetary accretion evolved relatively rapidly (in the greater scheme of things...) orders of magnitude ranging from 10^4 up to 10^6... and this involved some pretty hectic parties between planetesimals and protoplanets ... lots of shattering, vaporising, reforming, and getting tossed around&#33; :ph34r:

Younger chondrules could mean two things ... they were a by-product of some planetary wanna-bes getting &#39;up close and personal&#39; in the general chaos ... or they are late arrivals in the neighbourhood ... perhaps after being tossed out of another neighbourhood...? :huh:

Uranut
2005-Aug-22, 06:36 PM
I&#39;m with you, Cran

&#39;Impact&#39; theories are the current rage. Obviously, impacts between large bodies would have to occur after enough time had passed for those bodies to form. Seems to me the article supports current theory rather than defying it.

cran
2005-Aug-22, 06:53 PM
"Smashing&#33;" :D

Fraser
2005-Aug-23, 06:46 PM
SUMMARY: A researcher from the University of Toronto has found unexpectedly young material in meteorites, challenging theories about early events in the formation of the Solar System. A paper published in Nature reports that key minerals called chondrules have been found in meteorites that formed much later than the initial nebula that collapsed to form our Solar System. Instead, these chodrules were probably created when two newly forming planets smashed together.

View full article (http://www.universetoday.com/am/publish/discovery_of_chondrules_in_meterorites.html)

What do you think about this story? Post your comments below.

om@umr.edu
2005-Aug-23, 06:49 PM
Hi, Fraser.

An interesting story.

I will hold judgement until I have read the paper.

There is very strong evidence that many, many chrondrules were produced in one early, flash heating event.

Perhaps the event that ignited H-fusion in the Sun.

With kind regards,

Oliver
http://www.umr.edu/~om

lswinford
2005-Aug-23, 08:13 PM
Umm, how old is not old?

I was reading a bit ago about some "high temperature" superconductive magnet tests. I had to write the author to discover that she was talking about such high temperatures as "A typical "high" temp is, say, 130K, or about -226 degrees Fahrenheit."

So, in this story, how old is not as old as they were expecting those meteorite material to be? Did they mean something like, &#39;it should be 6byrs if of the original nebula but its only 4byrs&#39;?

cran
2005-Aug-23, 08:29 PM
Yes, the implication is something very much like that, but more 5bn instead of 6bn... with the suggestion that these inclusions formed from the planetary accretion process itself rather than during one of the earlier phases ...

And this discussion was already begun in "Other Stories" - don&#39;t recall who started it, but maybe someone clever can link the two threads? :huh:

Duane
2005-Aug-23, 08:53 PM
Which story are you referring to cran?

cran
2005-Aug-23, 09:36 PM
Hi Duane, I think it&#39;s the one called "Monkey Wrench in the Solar System?", started by BuzzLightBeer... :huh: it&#39;s only a day or so old...

Duane
2005-Aug-23, 09:57 PM
Found it, done. ;)

cran
2005-Aug-23, 11:15 PM
thank you, Duane; you&#39;re a champion&#33; :D

One thing the article does highlight (reading between the lines), and it has come up in other discussions... is the tendency in &#39;popular&#39; science reporting to slant a story for some kind of controversy - &#39;challenging current theories&#39; when such is not really the case - in this instance, the admittedly unexpected finding really does add support to a &#39;violent&#39; process of planetary accretion, which has been the majority consensus view since at least the mid 1990&#39;s, and was a leading option for a couple of decades prior to that ... it was the lack of such findings up until now, that left a question mark. :huh:

I think many of you have been quite right when criticising the approach made by some of these publications or their writers ... science is interesting enough, and discoveries are exciting enough ... we don&#39;t really need media-created &#39;controversies&#39; and half-baked &#39;mysteries&#39; to sell the stories... do we? :unsure: