Chondrule evidence suggests ancient low-velocity collisions between rocky planetesimals and icy bodies

Chondrule evidence suggests ancient low-velocity collisions between rocky planetesimals and icy bodies
An optical image showing magnetite-bearing chondrules studied in this work. Credit: Yves Marrocchi
(Phys.org)—A small team of researchers with members from institutions in France and Japan has found evidence in chondrules that suggest their existence came from collisions between planetesimals in the inner part of the solar system and icy bodies on the periphery, approximately four and a half billion years ago. In their paper published in the journal Science Advances, the team describes their work with two previously found meteorites and their study of the chondrules within them.

Space scientists have been studying meteorites for many years as part of their attempt to understand the nature of the universe—one type, chondrites, hold glassy looking blobs of material in their interior, called , which come to exist, it is believed, when molten droplets of different types of material cool. Such objects are also believed to belong to a class of some of the oldest known materials in our solar system. In this new effort, the researchers focused on two chondrites named Kaba and Vigarano.

In taking a close look at the chondrules within, the researchers found that they were made of sulfide-associated magnetites of magmatic origin, more commonly known as SAMs, something that had never been seen in a chondrule before. This, and their unique shape, the researchers contend, suggests that they could have been created only under conditions where oxidizing was occurring, and the only viable scenario where that could have occurred in the early solar system was where rocky planetesimals left the inner part of the solar system and ventured to its outer reaches where they eventually collided with icy bodies. Such collisions, the team notes, would have been relatively low velocity, because olivines were still present—a high speed collision would have caused such material to vaporize.

Chondrule evidence suggests ancient low-velocity collisions between rocky planetesimals and icy bodies
A picture of the thin section of the Vigarano meteorite that has been used in this study. Credit: Yves Marrocchi

The team built a model to better understand how such collisions could occur and after studying their results theorize that such collisions could have come about due to the presence of a gas giant, such as Saturn or Jupiter—as it formed, it could have caused other objects to be jerked around, resulting in some being flung great distances.

The findings by the team suggest that not all chondrules were made from primitive dusk present in the early disk—some may have come about due to collisions. The team plans to continue their study of chondrules looking for evidence that shows that collisions are the main process driving their formation.


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More information: Y. Marrocchi et al. Early scattering of the solar protoplanetary disk recorded in meteoritic chondrules, Science Advances (2016). DOI: 10.1126/sciadv.1601001

Abstract
Meteoritic chondrules are submillimeter spherules representing the major constituent of nondifferentiated planetesimals formed in the solar protoplanetary disk. The link between the dynamics of the disk and the origin of chondrules remains enigmatic. Collisions between planetesimals formed at different heliocentric distances were frequent early in the evolution of the disk. We show that the presence, in some chondrules, of previously unrecognized magnetites of magmatic origin implies the formation of these chondrules under impact-generated oxidizing conditions. The three oxygen isotopes systematic of magmatic magnetites and silicates can only be explained by invoking an impact between silicate-rich and ice-rich planetesimals. This suggests that these peculiar chondrules are by-products of the early mixing in the disk of populations of planetesimals from the inner and outer solar system.

Journal information: Science Advances

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Jul 04, 2016
Poor attempt, change the existing paradigm.
The collapse of gas now has more centers (Sun, Saturn, etc.) and gas with end of the nebula approached near the center and is free!
It is suggested now different age of the planet (How Great is)?
Which physics article representing?
This is just another an attempt to evade "Weitter Duckss's Theory of the Universe" http://www.svemir...Universe on irregular method.
Meteoritic chondrules (among others) have an orbit that approaches the Sun and thus create a structure (depending on the proximity of approach) Sun (as 67P / Churyumov-Gerasimenko).

Jul 04, 2016
Would you mind NOT using google translate? Your posts are just garbled words.

Jul 04, 2016
This comment has been removed by a moderator.

Jul 05, 2016
antialias_physorg 5 /5 (1) 1 hour ago
Would you mind NOT using google translate? Your posts are just garbled words.


Yeah. Probably is in his native tongue as well.



It does not look better, but that's the price of new technology.

Jul 05, 2016
It does not look better, but that's the price of new technology.

Well, in that case you're better off not posting at all. Because with your current posts you're just taking up space and not getting anything accross.

Jul 05, 2016
But even if he/she did get something across it is just meaningless trolling, so it would still be a waste of space.

If wduckss had something amounting to serious criticism of "the existing [science knowledge]" he/she could publish it and it would be read by people who appreciate the input.

Here it is just annoying garbage, "That struts and frets his hour upon the stage. And then is heard no more: it is a tale. Told by an idiot, full of sound and fury, Signifying nothing."

Jul 06, 2016
This comment has been removed by a moderator.

Jul 07, 2016
" This ... suggests that they could have been created only under conditions where oxidizing was occurring, and the only viable scenario where that could have occurred in the early solar system was where rocky planetesimals left the inner part of the solar system and ventured to its outer reaches where they eventually collided with icy bodies. Such collisions, the team notes, would have been relatively low velocity, because olivines were still present—a high speed collision would have caused such material to vaporize.

Low velocity collisions? Interesting. A meteorite travels from inner to outer solar system and gently collides. Is a gentle collision even possible? I've never heard of such a thing. All the meteorites that hit earth seem quite high velocity. Just how low is low I wonder?

Admittedly, it does seems a bit strange to think that flinging debris forms chondrules, but it doesn't disrupt asteroid rings. Not sure if that hypothesis is viable.

Can it be tested?

Jul 09, 2016
@tj: These things happened while the young sun and the proto-planetary disk was still around, so all sorts of brake mechanisms were present (magnetic braking from the coalescent star, viscous and gravitational damping in the disk), and nearby particles orbited with about the same velocities relative to the star.

The situation isn't easy to compare with today, when remaining particles rotate at very different relative velocities and there are little in the way of braking.

The asteroid rings formed as teh disk disappeared. There are all sorts of models where they test these scenarios, and compare with data from other systems. (They can see ring sizes and densities, and impact rates from how much dust is created, et cetera.)

Jul 09, 2016
LOL, low velocity impacts. A much simpler explanation of both the chondrules and the presence of the olivine is an electric discharge event. No magical "just right" Goldilocks inspired collisions are needed.

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