Blog dedicated primarily to randomly selected news items; comments reflecting personal perceptions

Sunday, June 15, 2014


"It would have been a very, very bad day for the Earth. One potential outcome could have been complete destruction."
"Subsequent to that bad day, it was a good thing."
"It's quite possible that by probing material from the deep Earth we may learn something more about the different formation stages of the Earth, how it was put together... We don't quite know what fraction melted, what vaporized, what stayed solid."
Sujoy Mukhopadhyay, associate professor, Earth and Planetary sciences, Harvard University
Apollo 8 astronauts took this photo of the Earth while on the Moon. Scientists say the Moon was created when the Earth collided with another planet 4.5 billion years ago.
NASA   Apollo 8 astronauts took this photo of the Earth while on the Moon. Scientists say the Moon was created when the Earth collided with another planet 4.5 billion years ago.
"This hypothesis [the Big Splash] can explain a lot of features of the moon, but there is one problem, that if you model this process [by computer], these computer models predict that most of the debris [that forms the moon] is coming from the impacting body [Theia], and because every body in the solar system has its own unique fingerprint, you would expect to have different isotopic compositions of the Earth and the Moon."
"Until now, this difference has not been found, and we've now found it."
"We really don't know if we could find this material anywhere on Earth ... We don't know if it's anywhere. It might have been all mixed away."
"If I find this, if you can give me like 10 milligrams of proto-Earth, I could tell you how large the impactor was and what its composition was. This would be very exciting, but currently we have no idea where that might be in the Earth."
Daniel Herwartz, University of Cologne, Germany

A new creation story, or at the very least, a theory of the Earth's final creation was presented at a geophysics conference that took place in California recently, of a violent collision in primordial space between what is called proto-Earth and a much smaller object named Theia. The result of which was a melding of the two through a force so powerful both were reduced to molten rock and silicate vapour.

This collision has been named the Big Splash. An event that spun the earth, and tilted its axis by 23 C, creating the moon from the resulting debris blasted into orbit. This might-have-been cataclysmic collision resulted in the Earth that presents itself today, and the moon that shines overhead. It resulted in the protective atmosphere of the Earth, seasonal cycles, polar ice caps, moon-driven tides and the eventual emergence of life.

Mr. Mukhopadhyay has analyzed material derived from deep within the Earth, from places like Iceland and Hawaii where "mantle plumes" forcefully dredge up materials through volcanoes. He posits that though the initial impact reduced both planets  to melting stage through the force of the impact, the side opposite the collision on proto-Earth was shielded, remaining partially solid, settling into a layer deeply close to the Earth's molten iron core.

When the planetary crash occurred, gravity held all the succeeding exploded bits together, and they gradually settled into a slightly flattened sphere we call Earth and upon whose crust we all live and thrive. The occurrence represented what scientists name a "giant impactor".  As for the moon, it formed from the spinning detritus of the Big Splash, in less than a millennium: "Geologically that is incredibly fast", explained Mr. Mukhopadhyay.

And the date when that is intelligently hypothesized to have occurred? How does 4.5-billion years ago sound? A French team felt that the collision occurred 60 million years earlier than had been thought. In other words scientists believe Earth was formed about 40 million years after the solar system itself began its formation, the product of perhaps ten billion years of cosmic evolution.

The beginning, of course, was the Big Bang; an expansion with space and time flooding from a single point, creating a universe where matter and antimatter were created in almost equal measure, each contesting the other in existence to create the flash of light that telescopes of today are still capable of detecting, called the Cosmic Microwave Background. Because there was slightly more matter than antimatter, even though each set out to annihilate the other, when antimatter was exhausted, matter was left.

The gravitational pull of dark matter gathered the basic elements into strands that eventually came together to form stars, where hydrogen and helium fused to create heavier atoms. When the stars died and exploded they seeded the universe with stardust, over time forming into spinning discs of diffuse matter that eventually became asteroids, comets and planets orbiting newer stars distributed within spiral galaxies.

One of those stars was our very own Sun which back then had perhaps 20 planets orbiting it, including proto-Earth and Mars-sized Theia. How's that for a creation story?

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