Formation of the moon brought water to Earth

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The Earth is unique in our solar system: It is the only terrestrial planet with a large amount of water and a relatively large moon, which stabilizes the Earth's axis. Both were essential for Earth to develop life. Planetologists at the University of Münster (Germany) have now been able to show, for the first time, that water came to Earth with the formation of the Moon some 4.4 billion years ago. The Moon was formed when Earth was hit by a body about the size of Mars, also called Theia. Until now, scientists had assumed that Theia originated in the inner solar system near the Earth. However, researchers from Münster can now show that Theia comes from the outer solar system, and it delivered large quantities of water to Earth. The results are published in the current issue of Nature Astronomy.

From the outer into the inner solar system

The Earth formed in the 'dry' inner solar system, and so it is somewhat surprising that there is water on Earth. To understand why this the case, we have to go back in time when the solar system was formed about 4.5 billion years ago. From earlier studies, we know that the solar system became structured such that the 'dry' materials were separated from the 'wet' materials: the so-called 'carbonaceous' meteorites, which are relatively rich in water, come from the outer solar system, whereas the drier 'non-carbonaceous' meteorites come from the inner solar system. While previous studies have shown that carbonaceous were likely responsible for delivering the water to Earth, it was unknown when and how this carbonaceous material—and thus the water—came to Earth. "We have used isotopes to answer this question. The molybdenum isotopes allow us to clearly distinguish carbonaceous and non-carbonaceous material, and as such represent a 'genetic fingerprint' of material from the outer and ," explains Dr. Gerrit Budde of the Institute of Planetology in Münster and lead author of the study.

The measurements made by the researchers from Münster show that the molybdenum isotopic composition of the Earth lies between those of the carbonaceous and non-carbonaceous meteorites, demonstrating that some of Earth's molybdenum originated in the outer solar system. In this context, the chemical properties of molybdenum play a key role because, as it is an iron-loving element, most of the Earth's molybdenum is located in the core. "The molybdenum which is accessible today in the Earth's mantle, therefore, originates from the late stages of Earth's formation, while the molybdenum from earlier phases is entirely in the core," explains Dr. Christoph Burkhardt, second author of the study. The scientists' results therefore show, for the first time, that carbonaceous material from the outer solar system arrived on Earth late.

But the scientists are going one step further. They show that most of the molybdenum in Earth's mantle was supplied by the protoplanet Theia, whose collision with Earth 4.4 billion years ago led to the formation of the Moon. However, since a large part of the molybdenum in Earth's mantle originates from the , this means that Theia itself also originated from the outer . According to the scientists, the collision provided sufficient carbonaceous material to account for the entire amount of water on Earth. "Our approach is unique because, for the first time, it allows us to associate the origin of on Earth with the formation of the Moon. To put it simply, without the Moon there probably would be no life on Earth," says Thorsten Kleine, Professor of Planetology at the University of Münster.


Explore further

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More information: Gerrit Budde et al, Molybdenum isotopic evidence for the late accretion of outer Solar System material to Earth, Nature Astronomy (2019). DOI: 10.1038/s41550-019-0779-y
Journal information: Nature Astronomy

Citation: Formation of the moon brought water to Earth (2019, May 21) retrieved 16 June 2019 from https://phys.org/news/2019-05-formation-moon-brought-earth.html
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May 21, 2019
From the abstract: " As most of the Mo in the primitive mantle was delivered by late-stage impactors10, our data demonstrate that Earth accreted carbonaceous bodies late in its growth history, probably through the Moon-forming impact."

Their figure 4 shows that the difference in likelihood between Theia and late veneer volatile delivery is minute. And their protoEarth mantle fits better with such delivery as well, inconsistent with their own claim in the article here of Theia being a one off event (but maybe the paper says something more on that point).

May 21, 2019
From the abstract: " As most of the Mo in the primitive mantle was delivered by late-stage impactors10, our data demonstrate that Earth accreted carbonaceous bodies late in its growth history, probably through the Moon-forming impact."

Their figure 4 shows that the difference in likelihood between Theia and late veneer volatile delivery is minute. And their protoEarth mantle fits better with such delivery as well, inconsistent with their own claim in the article here of Theia being a one off event (but maybe the paper says something more on that point).


http://sci-hub.se...9-0779-y

May 21, 2019
Moon was not formed by any impact. Theia is fictitious just like Vulcun. I am appalled that scientists are treading on a wrong track, even when all evidences are against the impact theory.

May 21, 2019
feel free guptm, to present your verified & confirmed by peer-reviewed evidence against the hypothesized Theia conjecture.

What speculation do you offer, instead?
How do you intend to prove it?

May 22, 2019
Here we go again, some claiming the moon was formed by a collision with a large object, when the physics just doesn't support such a hypothesis. And now claiming that it "delivered" water to earth at the same time. And such conjectures are now presented as fact (see the title). This is not science, it is fairy tales.

May 22, 2019
Here we go again, some claiming the moon was formed by a collision with a large object, when the physics just doesn't support such a hypothesis. And now claiming that it "delivered" water to earth at the same time. And such conjectures are now presented as fact (see the title). This is not science, it is fairy tales.

We need to trust your word when you believe a book 2000 years old to be correct in every way? Hmm, no. Provide the physics please.

Unlike you, I can provide support: https://en.wikipe...pothesis

"The giant-impact hypothesis is currently the favored scientific hypothesis for the formation of the Moon"

May 22, 2019
The moon is far too symetrical to have been formed as the result of an impact. I would believe that it is made of cheese before i put any stock in this "study"
. Last week "scientists" took a billion years off the age of the universe. This should be under Sci-fi.

May 22, 2019
Bart & KJV, what are your qualifications to criticize or even critique the work of any scientist?

Hell, I would take the word of the fabled Dutch cobbler, the Ultracrepidarianist, over either of you ignorant prats!

May 22, 2019
Moon was not formed by any impact.

The moon is far too symetrical to have been formed as the result of an impact.


That is what the evidence says - the angular momentum, element ratios and isotope ratios pf the system [ https://en.wikipe...pothesis ]. As cortezz says.

Last week "scientists" took a billion years off the age of the universe.


They did not, the difference between local and global expansion rate (which decides age) has been open for years. Now one group added better evidence for their hypothesis that the local universe is expanding faster. But the other side has *all* the data and has verified that a different local rate is a very complicated thing if it is real.

This is simply a long outstanding question; and it should be obvious that the popular reporting will be erroneous and overblown. Or did you not put genuine effort into understanding the issue before trolling?

Both blocked for inane trolling.

May 23, 2019
"News" like this one are so so VERY underwhelming. Scientists today are simple UNABLE to use words like probably, likely, best explanation. They put out these half cooked theories (that seem lesser than a hypotheses at their best.

How many moon "theories" we had in the last say 50 years? All of them full of critical holes and dropped only when:

* the excuses/arguments ran out of "road"
* another *notion* was proposed

This is so BAD! Makes scientists pushing these to look like fools, childish ego-tripping fools. Take this last one for instance. "A Mars sized object collided with Earth" Wow... before even trying to explain how the orbits of the bodies after this planetary crash became this perfect circles we see today, or how all the water "survived" the Herculaneum impact. These are mysteries, right?!
No, we go after molybdenum, because apparently... this is the solution for all this notion's problems, right?! I mean, just say you have no solid idea, stop STATING these "truths".

May 23, 2019
TG, you are the one I see stating that only you know the "truth"
you are just an anti-science deniertroll , agitpropping from your Dark Web site,

What empirical evidence verified & confirmed by peer0review, do you have to offer as proof against the conjectures these researchers present?

May 23, 2019
@guptm
@Bart_A.

Consider the early solar system. Then consider the 'surviving' planets which eventually settled into the patterns we see today...along with the many moons of Jupiter etc as well as our own. The impact craters still evident on some of those planets/moons is an indication of the huge range and frequency of collisions in the far past. The largest such collisions would not leave a 'crater', but would mangle/heat the planets/moons involved to such an extent, and re-distributed the molten debris, such that coalescing debris trapped in mutual orbits would form the dominant point and lesser bodies re-accreting from remaining debris to form moons etc. The molten material would form spherical bodies if gravity was sufficient to compress the material and re-melt it via compression/tidal 'heating'.

So large enough moons would be spherical like our Moon and Jupiters/Saturns etc moons.

Any counter-hypothesis would have to deny these observable physical processes. :)

May 23, 2019
Wow... before even trying to explain how the orbits of the bodies after this planetary crash became this perfect circles we see today
uh theyre not. This is how we know god doesnt exist.

May 24, 2019
Tell em @TheGhostofOtto1923

May 24, 2019
RC, that is also why, among the asteroids, Ceres is a globe. When so many are lumped together potatoe shapes.

Why the larger trans-Neptune ice-planetoids such as Pluto are sort of round.

Though I wonder about the efficacy, the energy-cost for tidal-melting of the cores of the ice-planetoids?
A phenomena common to the rocky worlds.

May 25, 2019
Scientists today are simple UNABLE to use words like probably, likely, best explanation. They put out these half cooked theories (that seem lesser than a hypotheses at their best.


Anyone really interested in the subject would know that the peer reviewed papers are carefully worded and statistically robust, or they would not be published. In some cases there are no other observations or theories to compare with, they have been rejected, so "best explanation" is rarely seen in robust areas. Moon formation by giant impact is solid, the water (volatile) delivery to Earth is quite open (but comets are excluded as main source and the isotopic inventory puts it as mainly local derived),

Certainly *this* paper can be criticized - I have - and it is possible to think it should nor have slipped through the cracks of peer review in its current form. But that is just proof of the pudding, science works.

However, your own claim is precisely 'ego-tripping foolish'. On the border of block.

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