The Earth and Moon formed later than previously thought

Jun 07, 2010
Photo of the Earth rising over the moon’s horizon, taken from the Apollo 8 mission. Image credit: NASA.

The Earth and Moon were created as the result of a giant collision between two planets the size of Mars and Venus. Until now it was thought to have happened when the solar system was 30 million years old or approx. 4,537 million years ago. But new research from the Niels Bohr Institute shows that the Earth and Moon must have formed much later - perhaps up to 150 million years after the formation of the solar system.

The research results have been published in the scientific journal, .

"We have determined the ages of the and the Moon using tungsten isotopes, which can reveal whether the iron cores and their stone surfaces have been mixed together during the collision", explains Tais W. Dahl, who did the research as his thesis project in geophysics at the Niels Bohr Institute at the University of Copenhagen in collaboration with professor David J. Stevenson from the California Institute of Technology (Caltech).

Turbulent collisions

The planets in the were created by collisions between small dwarf planets orbiting the newborn sun. In the collisions the small planets melted together and formed larger and larger planets. The Earth and Moon are the result of a gigantic collision between two planets the size of Mars and Venus. The two planets collided at a time when both had a core of metal (iron) and a surrounding mantle of silicates (rock). But when did it happen and how did it happen? The collision took place in less than 24 hours and the temperature of the Earth was so high (7000º C), that both rock and metal must have melted in the turbulent collision. But were the stone mass and iron mass also mixed together?

Until recently it was believed that the rock and iron mixed completely during the and so the conclusion was that the Moon was formed when the solar system was 30 million years old or approximately 4,537 million years ago. But new research shows something completely different.

Dating with radioactive elements

The age of the Earth and Moon can be dated by examining the presence of certain elements in the Earth's mantle. Hafnium-182 is a radioactive substance, which decays and is converted into the isotope tungsten-182. The two elements have markedly different chemical properties and while the tungsten isotopes prefer to bond with metal, hafnium prefers to bond to silicates, i.e. rock.

It takes 50-60 million years for all hafnium to decay and be converted into tungsten, and during the Moon forming collision nearly all the metal sank into the Earth's core. But did all the tungsten go into the core?

"We have studied to what degree metal and rock mix together during the planet forming collisions. Using dynamic model calculations of the turbulent mixing of the liquid rock and iron masses we have found that tungsten from the Earth's early formation remain in the rocky mantle", explains Tais W. Dahl, Niels Bohr Institute at the University of Copenhagen.

The new studies imply that the moon forming collision occurred after all of the hafnium had decayed completely into tungsten.

"Our results show that metal core and rock are unable to emulsify in these collisions between planets that are greater than 10 kilometres in diameter and therefore that most of the Earth's iron core (80-99 %) did not remove from the rocky material in the mantle during formation", explains Tais W. Dahl.

The result of the research means that the Earth and the must have been formed much later than previously thought - that is to say not 30 million years after the formation of the solar system 4,567 million years ago but perhaps up to 150 million years after the formation of the solar system.

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Provided by University of Copenhagen

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mysticshakra
1.4 / 5 (19) Jun 07, 2010
Actually it says reformed as the earth was in ruins.

Alternatively, pretending we know the age of the earth or how it formed is pretty silly. The only thing larger than our ignorance is our arrogance.
xamien
3.2 / 5 (13) Jun 07, 2010
You guys have it all wrong: It was formed by the Flying Spaghetti Monster during a bad case of indigestion. All Pastafarians know this.
Parsec
4 / 5 (10) Jun 07, 2010
If nothing else, this research follows the right direction... In Bible Earth was formed 4004 B.C. (derived by adding the lengths of the lives of the patriarchs, as given in Genesis 5 and 11).


Do you enjoy the mental image of your Patriarchs swimming in 7000 degree magma? I saw a old movie of Dante's inferno once that had a bunch of dudes swimming in lava but I don't think they were direct descendent's of Adam and Eve.
PinkElephant
5 / 5 (2) Jun 07, 2010
For my part, I fail to see the connection between this:
Our results show that metal core and rock are unable to emulsify in these collisions between planets that are greater than 10 kilometres in diameter
and this:
The two elements have markedly different chemical properties and while the tungsten isotopes prefer to bond with metal, hafnium prefers to bond to silicates, i.e. rock.
If core and mantle failed to mix in the collision, then why does it matter whether or not all Hafnium in the mantle already converted to Tungsten or not? In the end, you end up with the same result: Tungsten-182 in the mantle -- and the result is due to the mantle and core having failed to emulsify in the collision, rather than to the time when the collision might have happened... So how can this have any bearing on the timing of the collision, again?

What am I missing here??
verkle
1.8 / 5 (16) Jun 07, 2010
Really silly conjectures.
And it is stated as fact!
Let's move on to real science and physics.
kevinrtrs
1.3 / 5 (16) Jun 08, 2010
What happens when two rocks moving at just about ANY speed collide? What happens when one solid object bumps into the other?
Please show me where it happens that these obejcts fuse together in any manner or form.

This is terrible conjecture being passed as science - it doesn't even get past the high school science experiments showing preservation of momentum.

Are these gentle people really trying to say that the bodies were soft and hot pieces of magma flying around in space? How did they get to be in that state?
Please spare us!!!!
PinkElephant
4.6 / 5 (11) Jun 08, 2010
@kevinrtrs,

You need to learn some humility, and spare US. Just because your high school education limits your comprehension and insight, doesn't mean the world is as limited as your perception.

In the case of large objects (like planets), collisions are inelastic. Rock can be hard, but no rock is hard enough to withstand the momentum of an entire planet impacting it. When put under sufficient pressure, rock of any hardness will flow like a fluid because ultimately it's just a matter of breaking bonds between atoms, which is easily accomplished given enough energy. That's aside from the fact that such collisions will generate enormous amounts of heat, which would melt and even vaporize large portions of the bodies involved.

Here's a narrated example of such a simulation:

http://www.youtub...4MdN5wo0
Adriab
not rated yet Jun 08, 2010
The Earth and Moon were created as the result of a giant collision between two planets the size of Mars and Venus.

I sure am glad to have that cleared up.

But anyway, I agree with PinkElephant, the connections drawn in this article seem tenuous at best. Its that or the writer lost a lot of facts when making this article.

Anyone have a link to the actual published results?
iKnighty
5 / 5 (5) Jun 08, 2010
If nothing else, this research follows the right direction... In Bible Earth was formed 4004 B.C. (derived by adding the lengths of the lives of the patriarchs, as given in Genesis 5 and 11).

You can't add the length of the lives of the patriarchs to get the length of the Earth. Disregarding the lack of scientific validity of the Bible, it's not like each patriarch was born at the moment of death of his father.
Shootist
3.5 / 5 (8) Jun 08, 2010
@kevinrtrs,

You need to learn some humility, and spare US. Just because your high school education limits your comprehension and insight, doesn't mean the world is as limited as your perception.

In the case of large objects (like planets), collisions are inelastic. Rock can be hard, but no rock is hard enough to withstand the momentum of an entire planet impacting it. When put under sufficient pressure, rock of any hardness will flow like a fluid because ultimately it's just a matter of breaking bonds between atoms, which is easily accomplished given enough energy. That's aside from the fact that such collisions will generate enormous amounts of heat, which would melt and even vaporize large portions of the bodies involved.

Here's a narrated example of such a simulation:

http://www.youtub...4MdN5wo0


Impacts at 20km/sec or higher are significantly energetic to create large quantities of plasma. Two planets impact? Continents are atomized and ionized.
Shootist
1 / 5 (3) Jun 08, 2010
Assuming interplanetary velocities.


French B. M. (1998) Traces of Catastrophe: A Handbook of Shock-Metamorphic Effects in Terrestrial Meteorite
Impact Structures. LPI Contribution No. 954, Lunar and Planetary Institute, Houston. 120 pp. with some insights into energetic impacts.

http://www.lpi.us...-954.pdf
Skeptic_Heretic
5 / 5 (4) Jun 08, 2010
Actually it says reformed as the earth was in ruins.

Alternatively, pretending we know the age of the earth or how it formed is pretty silly. The only thing larger than our ignorance is our arrogance.
It's called radiometric dating.
If nothing else, this research follows the right direction... In Bible Earth was formed 4004 B.C. (derived by adding the lengths of the lives of the patriarchs, as given in Genesis 5 and 11).

This is so stupid I almost don't want to respond.

You were definitely homeschooled, Alizee, and by idiot creationists.
omatumr
1.4 / 5 (10) Jun 09, 2010
An inventory of radioactive and stable noble gas isotopes in the Earth and its atmosphere indicates that the Earth formed heterogeneously (in layers) beginning with the formation of its iron core from iron-rich supernova (SN) debris near the SN core on which the Sun formed ["The noble gas record of the terrestrial planets", Geochemical Journal 15 (1981) 247-267].

With kind regards,
Oliver K. Manuel
Emeritus Professor
Nuclear & Space Sciences
Former NASA Principal Investigator for Apollo
rhapsodist
5 / 5 (3) Jun 12, 2010
Actually it says reformed as the earth was in ruins.

Alternatively, pretending we know the age of the earth or how it formed is pretty silly. The only thing larger than our ignorance is our arrogance.


If nothing else, this research follows the right direction... In Bible Earth was formed 4004 B.C. (derived by adding the lengths of the lives of the patriarchs, as given in Genesis 5 and 11).


In ancient scriptures, the "earth" is a metaphor for the societal structures of any given religion (i.e. the relationships between people and other people) and the "heavens" refer to the relationships between people and God. Thus the "earth" was created when the 'word of God' was brought to people by the first 'prophet'

Basically, it has nothing to do with the physical formation of the planet we call "earth"
Quantum_Conundrum
1.6 / 5 (5) Jun 12, 2010
You can't add the length of the lives of the patriarchs to get the length of the Earth. Disregarding the lack of scientific validity of the Bible, it's not like each patriarch was born at the moment of death of his father.


First of all, he mis-stated how this number was obtained. It was obtained by finding the AGE of the father at the time each Son was born, because this is recorded in nearly every case, and then adding those numbers up. Because it is stated exactly how old each father was when their first born son was born. Except for two discontinuities, but the length of one of these is given exactly elsewhere in the Bible, and the length of the other discontinuity is known almost exactly from a combination of the Bible and "secular" history.

Secondly, the number "4004b.c." is actually wrong, given the above information. When I did the calculation my self, I came to the sum of something like ~4700B.C., but it's been several years since I did this.
Quantum_Conundrum
1 / 5 (5) Jun 12, 2010
rhapsodist:

You are quite clearly wrong. Exodus 20:11 specifically states that God made, "heaven, the earth, and the sea and everything that is in them in six days, and rested on the seventh."

The literal interpretation is the only one that was taught in the New Testament as well.

Heb. 11:3Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear.

Note that the greek word here translated "worlds" is actually "Aion", which implies perpetuity, or eternity, or indeed the entire universe.

Which is why it was translated as the plural "worlds" rather than the singular "world" or "earth".

In exoduse 20 and Gen. 1:1, "Earth" is from the Hebrew "erets for "earth or Land".

While "Heaven" is from "shameh" which is "lofty, the sky, or celestial ether".

Finally, John 1:1 totally refutes your claim, because John clearly interprets Genesis as the literal creation of everything by God.
cmorrill321
1 / 5 (1) Jun 12, 2010
If nothing else, this research follows the right direction... In Bible Earth was formed 4004 B.C. (derived by adding the lengths of the lives of the patriarchs, as given in Genesis 5 and 11).


AHHAHA. That was my first thought!
gwrede
1 / 5 (1) Jun 12, 2010
The result of the research means that the Earth and the Moon must have been formed much later than previously thought - that is to say not 30 million years after the formation of the solar system 4,567 million years ago but perhaps up to 150 million years after the formation of the solar system.
Maybe I just skimmed the article and missed something, but it sounds to me that "up to 150My" should rather be "at least 150My". Considering what they explained.
trekgeek1
5 / 5 (6) Jun 13, 2010
It's painful to hear these people. I think there should be a bible filter on this site. It anybody quotes a verse or mentions the book, the comment should be deleted. All these people loving that ~4.5 billion years old became ~4.4 billion years old really gets them off even though they're still off by a factor of around a million with 4,400 years. Please shut down your physorg profile if you're going to spit in science and reason's face every time you get a chance. You got so many down votes because this isn't YouTube. Stupid comments get voted down. Go to YouTube if you want people to value nonsense. Science and reason rule. They always think numbers are bigger, then smaller, then bigger, etc. That's how you converge to the actual number.
71STARS
1 / 5 (9) Jun 13, 2010
Until you abandon the grave error that planets "were created by collisions between dwarf planets orbiting the newborn sun" -- you will never get the sequence of events correct. My belief puts forth the creation of the universe, suns, planets, and moons, directly upon the initial creation of a First Sun. (no big bang) (no rogue collisions) dwyersuncreation@aol.com
71STARS
1 / 5 (6) Jun 13, 2010
An inventory of radioactive and stable noble gas isotopes in the Earth and its atmosphere indicates that the Earth formed heterogeneously (in layers) beginning with the formation of its iron core from iron-rich supernova (SN) debris near the SN core on which the Sun formed ["The noble gas record of the terrestrial planets", Geochemical Journal 15 (1981) 247-267].

With kind regards,
Oliver K. Manuel
Emeritus Professor
Nuclear & Space Sciences
Former NASA Principal Investigator for Apollo

absolutely, the earth came from the sun. enough said.
trekgeek1
5 / 5 (4) Jun 13, 2010
..I think there should be a bible filter on this site. It anybody quotes a verse or mentions the book, the comment should be deleted...
I don't believe in Bible literally, but IMO it contains a number of deeper connections of reality, which have good meaning even from rigorous physics point of view. Any call for censorship is unscientific from this perspective. Of course, strictly formally thinking people cannot learn from fuzzy experience of many human generations well: they cannot follow information, when it's too diluted & omni-directional for them.


A call for censorship is not unscientific when you censor nonsense. Is filtering out vulgarities or pornography from this site unscientific? If I was trying to suppress a valid counter argument then it would be unscientific. You arguments are utter nonsense and don't deserve the privilege of contemplation.
cyberCMDR
5 / 5 (3) Jul 11, 2010
Can someone from the creationist side tell me how we can see galaxies billions of light years away, it the universe was "created" less than 10,000 years ago? If you can't reconcile a simple observable fact with your beliefs, re-evaluate them.
gwrede
1 / 5 (2) Jul 11, 2010
@cyberCMDR: God created light. What did you expect?
cmorrill321
not rated yet Jul 12, 2010
Can someone from the creationist side tell me how we can see galaxies billions of light years away, it the universe was "created" less than 10,000 years ago? If you can't reconcile a simple observable fact with your beliefs, re-evaluate them.


I know it's implied by your question, but please keep in mind that not all of us creationists believe in that "young earth" shit. Also, many of us believe in evolution. We aren't all fighting science with idiotic statements like, "God put dinosaur bones in the earth to test our faith."
To quote Bill Hicks:
"God put [dinosaur fossils] here to test our faith!" … I think God put YOU here to test my faith, dude. Does that bother anybody else, the idea that God might be f---ing with our heads? I have trouble sleeping with that knowledge, some prankster god runnin' around, [pantomimes digging] "We'll see who believes in me now!"
Unfortunate that the most vocal and known Christians tend to be the idiots.
(that's very un-Christian of me to say :P
cmorrill321
5 / 5 (1) Jul 12, 2010
Can someone from the creationist side tell me how we can see galaxies billions of light years away, it the universe was "created" less than 10,000 years ago? If you can't reconcile a simple observable fact with your beliefs, re-evaluate them.


I know it's implied by your question, but please keep in mind that not all of us creationists believe in that "young earth" crap. Also, many of us believe in evolution. We aren't all fighting science with idiotic statements like, "God put dinosaur bones in the earth to test our faith."
To quote Bill Hicks:
"God put [dinosaur fossils] here to test our faith!" … I think God put YOU here to test my faith, dude. Does that bother anybody else, the idea that God might be f---ing with our heads? I have trouble sleeping with that knowledge, some prankster god runnin' around, [pantomimes digging] "We'll see who believes in me now!"
Unfortunate that the most vocal and known Christians tend to be the idiots.
(that's very un-Christian of me to say :P

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