Study: Earth may 'remember' more of its infancy than previously thought

Ancient gases trapped deep within the Earth's mantle may reveal clues about our planet's earliest days, according to a new study.

For the past decade scientists believed our planet's memory was reset 4.5 billion years ago when an object the size of Mars slammed into the Earth, releasing enough energy to cause most of the Earth to turn into a liquid magma ocean.

Any clues to the planet's earlier past, scientists thought, likely got melted away in this last, great impact, which also created our moon.

However, Sujoy Mukhopadhyay, a geochemist at Harvard University has found evidence that the impact may not have affected the whole planet in the same way.

"The simulations we are doing now indicate that some regions got melted and vaporized, while the opposite side of the planet did not melt at all," he said Monday after presenting his research at the Goldschmidt conference in Sacramento.

Source

Some scientists believe that if the entire Earth did not melt, then that could mean there may be a few hidden vestiges of our planet from a time before the moon
And from that, scientists maybe able to learn more about the Earth's infancy and planetary formation in general

Studies done on volcanic rocks from different parts of the world, measured the gases trapped inside, and has been shown that the gases vary in volume in the shallow mantle vs. deeper mantle
Which means, that if the entire Earth became liquid after the last major impact 4.5 billion years ago, there would NOT be a difference in the isotope ratio in the two parts of the mantle

Therefore, the researchers conclude, only part of the mantle melted all the way at that time

Mukhopadhyay said the next step is to make more measurements of rocks from different hot spots around the world, and then use that information to build more realistic models of giant impacts.

"What this means is the Earth has memories that go back further than we thought," he said.


Very interesting, thought I would share this....

It's interesting to hear a new theory or hypothesis. I don't know how well this will be accepted by other scientists though. I'm not sure that a planet had to hit earth to do this though, there are other events that could probably trigger this also.

One hypothesis I read long ago was that the moon was part of something bigger that hit earth and rolled around it loosing and gaining as it rolled. I liked that idea. I wonder if I can find that somewhere on the net. It may not be true, but it was an interesting concept.

a reply to: rickymouse

One hypothesis I read long ago was that the moon was part of something bigger that hit earth and rolled around it loosing and gaining as it rolled. I liked that idea. I wonder if I can find that somewhere on the net. It may not be true, but it was an interesting concept.

Apollo rocks hint at Moon's violent birth after collision on Earth

Now, in a study published in the journal Science, a team of German researchers say they’ve finally found clear signs in Apollo-era rock to support major theories about the moon’s creation story.

So most moons are either adopted or they’re their planet's little siblings, born of essentially the same stuff. But Earth’s moon was sired after a brief and ill-fated encounter with a smaller, Mars-sized proto-planet named Theia, which came barreling through space and crashed into Earth’s surface. Chunks of Earth and Theia went flying, eventually coalescing into the moon.

According to many accepted models, the newly formed moon would be made mostly of Theia’s remains, with 70% to 90% being Theia debris and the rest (30% to 10%) being from Earth. This would explain a lot of things about the moon, the authors point out: why the lunar satellite seems to be so lacking in water and volatiles; why its lunar core is so small, and why the Moon and Earth move around each other in the particular way they do.

That is interesting too, I missed seeing that earlier....thanks

But like you stated tho, wonder how many in the scientific field will accept this latest theory? As in the OP as well??

a reply to: snarky412

Do they know which side got hit? I read or heard someone say the Pacific without water looks like a chunk of the Earth was taken away. I have also heard Theia or whatever celestial body, planet, planetoid, asteroid it was settled into our core, but obviously no proof to that theory, that I know of. The Ring of Fire may have a whole new meaning...more like the Cauldron of Hell. So, if the Eastern Hemi did not melt...we need to start looking into those cratons, they've been around forever, right? Heck, maybe the cratons are reminants of Theia all broke up and scattered across the globe? Just a thought.

a reply to: snarky412

I look at articles like this: lunar.ksc.nasa.gov... In the first paragraph it states that our moon is actually more like a terrestrial planet and is not like the other moons. Now, some scientists call it this but they are misguided. What we refer to as the moon has been recognized as such for many thousand years. It is a moon...well, it did have different names for this body by different cultures. Now the other moons of planets are not moons, they are not the same as our planets moon, the original moon. They should have renamed those as something different than trying to change the original perception, the basis for our understanding of moon. It is a point of perspective that is an issue, what we based all other planets moons discoveries on was from the knowledge of our own moon. The definition of our moon should remain a constant and the stuff that science named later should be altered...or just keep calling them all moons. No big deal.

originally posted by: Boscov
a reply to: snarky412

Do they know which side got hit? I read or heard someone say the Pacific without water looks like a chunk of the Earth was taken away. I have also heard Theia or whatever celestial body, planet, planetoid, asteroid it was settled into our core, but obviously no proof to that theory, that I know of. The Ring of Fire may have a whole new meaning...more like the Cauldron of Hell. So, if the Eastern Hemi did not melt...we need to start looking into those cratons, they've been around forever, right? Heck, maybe the cratons are reminants of Theia all broke up and scattered across the globe? Just a thought.

When you look back at the history of Earth's continents they all at one time were joined together into a single super-continent called Gondwanaland and Pangaea.

Of all the continents, Afghanistan has some of the oldest rocks in the world (Archean). They also have some of the oldest human artifacts dating 100,000 years ago.

www.bgs.ac.uk...

a reply to: rickymouse

Moons orbit the bodies of planets which orbit the sun.

In other words, we refer to those bodies that orbit an object other than our sun as "moons" or "satellites", not because of what makes them up, but because they are in orbit around a parent body that orbits the sun.

For example, if Jupiter ended up having a "moon" that is the same size and make up as our planet, Earth, it would still be referred to as a "moon of Jupiter", not because of what it is made up of, but simply because it orbits Jupiter, and not the sun.

a reply to: snarky412

Wow. Very, very cool - sounds quite reasonable to me.

F&S&