Lutetia: A rare survivor from the birth of the Earth

Lutetia: A rare survivor from the birth of the Earth
This image of the unusual asteroid Lutetia was taken by ESA’s Rosetta probe during its closest approach in July 2010. Lutetia, which is about 100 kilometres across, seems to be a leftover fragment of the same original material that formed the Earth, Venus and Mercury. It is now part of the main asteroid belt, between the orbits of Mars and Jupiter, but its composition suggests that it was originally much closer to the Sun. Credit: ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA
(PhysOrg.com) -- New observations indicate that the asteroid Lutetia is a leftover fragment of the same original material that formed the Earth, Venus and Mercury. Astronomers have combined data from ESA’s Rosetta spacecraft, ESO’s New Technology Telescope, and NASA telescopes. They found that the properties of the asteroid closely match those of a rare kind of meteorites found on Earth and thought to have formed in the inner parts of the Solar System. Lutetia must, at some point, have moved out to its current location in the main asteroid belt between Mars and Jupiter.

A team of astronomers from French and North American universities have studied the unusual asteroid in detail at a very wide range of wavelengths to deduce its composition. Data from the OSIRIS camera on ESA's Rosetta spacecraft, ESO's New Technology Telescope (NTT) at the La Silla Observatory in Chile, and NASA's Infrared Telescope Facility in Hawaii and Spitzer Space Telescope were combined to create the most complete spectrum of an asteroid ever assembled.

This spectrum of Lutetia was then compared with that of meteorites found on that have been extensively studied in the laboratory. Only one type of meteorite — enstatite chondrites — was found to have properties that matched Lutetia over the full range of colours.

Enstatite chondrites are known to be material that dates from the early Solar System. They are thought to have formed close to the young Sun and to have been a major building block in the formation of the rocky planets, in particular the Earth, Venus and . Lutetia seems to have originated not in the main belt of asteroids, where it is now, but much closer to the Sun.

"But how did Lutetia escape from the inner Solar System and reach the main asteroid belt?" asks Pierre Vernazza (ESO), the lead author of the paper.

have estimated that less than 2% of the bodies located in the region where Earth formed, ended up in the main asteroid belt. Most of the bodies of the inner Solar System disappeared after a few million years as they were incorporated into the young planets that were forming. However, some of the largest, with diameters of about 100 kilometres or more, were ejected to safer orbits further from the Sun.

Lutetia, which is about 100 kilometres across, may have been tossed out from the inner parts of the young if it passed close to one of the rocky planets and thus had its orbit dramatically altered. An encounter with the young Jupiter during its migration to its current orbit could also account for the huge change in Lutetia's orbit.

"We think that such an ejection must have happened to Lutetia. It ended up as an interloper in the main asteroid belt and it has been preserved there for four billion years," continues Pierre Vernazza.

Earlier studies of its colour and surface properties showed that Lutetia is a very unusual and rather mysterious member of the asteroid main belt. Previous surveys have shown that similar asteroids are very rare and represent less than 1% of the asteroid population of the main belt. The new findings explain why Lutetia is different -- it is a very rare survivor of the original material that formed the rocky planets.

"Lutetia seems to be the largest, and one of the very few, remnants of such material in the main . For this reason, asteroids like Lutetia represent ideal targets for future sample return missions. We could then study in detail the origin of the , including our Earth," concludes Pierre Vernazza.


Explore further

Lutetia asteroid in Rosetta's spotlight

More information: This research was presented in a paper, “Asteroid (21) Lutetia as a remnant of Earth’s precursor planetesimals”, to appear in the journal Icarus.
Journal information: Icarus

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Citation: Lutetia: A rare survivor from the birth of the Earth (2011, November 11) retrieved 26 May 2019 from https://phys.org/news/2011-11-lutetia-rare-survivor-birth-earth.html
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Nov 12, 2011
Iron meteorites were the first material that accreted to form iron cores of planets near the Sun.

Theses became accretion sites for stone meteorites that formed further away from the pulsar on which the Sun reformed.

"Inhomogeneous accumulation of the earth". Earth Planet. Sci. Lett. 6, 346-348 (1969)

"Elemental and isotopic inhomogeneities in noble gases: The case for local synthesis of the chemical elements", Transactions Missouri Academy Sciences 9, 104-122 (1975)

www.omatumr.com/D...Data.htm

"Strange xenon, extinct super-heavy elements, and the solar neutrino puzzle", Science 195, 208-209 (1977)

www.omatumr.com/a...enon.pdf

Is the Sun a pulsar? Nature 270, 159-160 (1977)

Evidence for a small, high-Z, iron-like solar core, Astron. Astrophys. 149, 65-72 (1985)

"Isotopic ratios in Jupiter confirm intra-solar diffusion", Meteoritics 33, A97, 5011 (1998)

www.lpi.usra.edu/...5011.pdf

O. Manuel
http://myprofile....anuelo09

Nov 12, 2011
Oliver Manuel's recent efforts to plaster Physorg.com and other public news sites with his theories and personal URLs are a bit puzzling, as scientists have a variety of publications available to communicate directly to each other in. My best guess is that he is desperately trying to prop up his legacy in light of his arrest in his university office on 7 charges of rape and sodomy based on allegations by 4 of his own children. The charges have been reduced to one count of felony attempted sodomy, not necessarily because of his innocence, but because of the statute of limitations. One can only guess how the recent charges and decades of family strife have affected his ability to reason rationally and to remain objective while defending his unpopular theories.

http://www.homefa...uel.html

http://mominer.ms...hildren/

ACW
Nov 12, 2011
Or perhaps the asteroid is a chunk of Earth that came loose after a major impact.

Nov 12, 2011
Not likely ACW. A major violent impact like that would leave detectable traces. Not the least of which would be metamorphised rock. Nothing like that has been detected so far and, given the precision available today, not likely to be suddenly found.

Nov 12, 2011
Iron meteorites were the first material that accreted to form iron cores of planets near the Sun.
That isn't how the iron cores formed. ALL those iron meteorites got hot enough to melt and THEN the iron moved in to the center of those rather large asteroids.

Theses became accretion sites for stone meteorites that formed further away from the pulsar on which the Sun reformed.
No. There was no pulsar. Your Neutron Repulsion theory proves they can't form. Of course there is no actual evidence of Neutron Repulsion except what is covered by the Pauli Exclusion Principle.

"Inhomogeneous accumulation of the earth". Earth Planet. Sci. Lett. 6, 346-348 (1969)
Which is entirely a wild assed guess wholly dependent on your Iron Sun theory and is not independent of it. There is no evidence to support it is just speculation on your part and it would likely be correct IF the Sun had a the rigid Iron Mantle you claim it does. Only there is no evidence for it.>>

Nov 12, 2011
"Strange xenon, extinct super-heavy elements, and the solar neutrino puzzle", Science 195, 208-209 (1977)
That is the same exact WAG based on and dependent on the Neutron-Iron Sun theory which is contrary to physics and evidence.

The Solar Neutrino puzzle isn't. The neutrinos are all accounted for. Have been since the Sudbury experiment showed that the three flavors of neutrinos, that were all coming from the Sun, add up to the correct amount. Further experiments have continued to confirm that evidence for neutrino oscillation. Competent scientist take new evidence into account. Its about time you did that.

Is the Sun a pulsar? Nature 270, 159-160 (1977)
No. IF Neutron Repulsion was correct than there can be no pulsars. How did you miss that and why haven't you answered the question?>>

Nov 12, 2011
Evidence for a small, high-Z, iron-like solar core, Astron. Astrophys. 149, 65-72 (1985)
No. That is evidence that a Super Nova was involved in the formation of the Solar System. Other evidence shows there may have been multiple SN and even a Wolf-Rayet involved. At present it appears there may have been a supernova of sort that is going to occur in the Carina Nebula when Eta Carinae goes boom.

"Isotopic ratios in Jupiter confirm intra-solar diffusion", Meteoritics 33, A97, 5011 (1998)
More of that circular reasoning. Its utterly dependent on a rather large number of ideas of yours that don't actually fit the evidence or known physics.

We are also still waiting for actual evidence that the Sun has a RIGID iron mantle. You have never posted anything that supports the idea.

Ethelred

Nov 13, 2011
Enstatite chondrites are known to be material that dates
from the early Solar System.


This kind of statement always bothers me because the phrase "are known to be..." is blatantly untrue when dealing with something like this, and it has no place in a scientific article.

If they had simply qualified the statement, saying "is believed to be..." or "is generally considered to be..." then the statement would be OK.

This is not simply a matter of splitting hairs - when scientists or science journalists (not sure who here is the culprit) state an actual unknown as if it is a definitive fact, it can easily lead to someone using that "fact" as a foundational "given" (possibly without them even knowing better) upon which they waste their efforts building a house of cards. At least, (just to be consistent) that seems to me to be the case.

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