New Study Challenges Theories About Moon’s Early History
The origins of the Moon have been the cause of many a scientific debate over the years but more recently we seem to have settled on a Mars-sized object crashing into Earth billions of years ago, with the debris coalescing into the Moon
The newly formed Moon drifted slowly away from Earth over the following eons, but a new study suggests some surprising nuances to the accepted model.
According to current theory, the Moon formed around 4.5 billion years ago, shortly after the Solar System’s birth. It began with a massive collision between the early Earth and a Mars-sized protoplanet called Theia.
The impact sent debris into orbit around the Earth which eventually coalesced to create the Moon.
There is plenty of evidence to support this theory, chiefly the composition of Earth’s mantle and lunar rocks.
While the majority of the debris cloud settled back down on the Earth, a large proportion formed the Moon but some of it was ejected from the Earth-Moon system.
In the paper recently authored by Stephen Lepp and his team from the University of Nevada they explored the dynamics of the material ejected from the impact.
Shortly after the Moon formed it was orbiting Earth at a distance about 5% of its current value (average distance – 384,400 km) but slowly, due to tidal effects between Earth and Moon it drifted away to its current altitude.
Its surface was largely molten magma which gradually cooled and solidified forming the familiar crust, mantle and core that we see today.
Heavy bombardment scarred the lunar surface with impact basins and craters and volcanic activity led to the slow formation of the lunar maria.
The orbit of the Moon around the Earth has settled into a slightly elliptical one with an eccentricity of 0.0549. It is not a perfect circle and moves from 364,397 km to 406,731 km from Earth.
The system wasn’t so stable in the early days of the Earth-Moon system and the particles in the accreting Moon had more erratic journeys.
One of the terms that describes evolving orbits is nodal precession (where the orbital intersections slowly move around the orbit). There are two types and the first relates to where particles in an orbit slowly precess about the angular momentum vector of the Earth-Moon system.
The other occurs around highly eccentric binary systems when the inclination of the orbiting object is large. The particle precesses about the binary eccentricity vector.
Taking into account the Earth and orbits of particles in the debris cloud as the Moon started to form, such orbits described would be unstable.
The team showed that of all the possible orbits of particles, those in polar orbits were the most stable. They went further and showed that they existed around the Earth-Moon binary system after the Moon formed.
As the separation of the Earth and Moon slowly increased through tidal interactions the region of space where polar orbits could exist decreased.
Today, with the Moon at its current distance from Earth, there are no stable polar orbits since the nodal precession driven by the Sun is dominant.
The team conclude that the presence of polar orbiting material can drive eccentricity growth of a binary system like the Earth and Moon.
If a significant amount of material found its way into a polar orbit then the eccentricity of the Earth-Moon system would have increased.
See more here sciencealert.com
Header image: Royal Museums Greenwich
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Herb Rose
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This theory shows that the study of physics has become training to believe in nonsense. When you can come up with a fantasy theory that is completely disconnected from reality you are ready to publish absolute crap and join the other ‘physicists” in protecting the fantasy they’ve created.
Now the goal is to create models then change reality to conform to the model. Hanson did it with the GHGT and got a job at NASA, where the creators of this model can surely find a well paying job.
They have created a theory that will save NASA billions (not that saving money is a consideration) by having satellites move into higher orbits when slowing down instead of burning up while falling back to Earth.
The “Experts” who accepted and published this paper in a scientific journal should be fired and have the word “STUPID” tattooed on their foreheads.
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Jerry Krause
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Hi Herb,
Why don’t we remember the actual history of this thing we term SCIENCE? Before Galileo proved that the Earth did not standstill with what he (and others) could see with his telescope, had anyone a hundred years earlier invented a furnace which produced enough heat to melt sand?
Often I disagree with what you write; but not this time. And you disagree with what I write. This is SCIENCE and sometimes someone observes something that proves some ideas must be absolutely WRONG; which ends the previous debate.
Have a good day
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Phil
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Thanks for posting.
Good response to Herb’s failed hatchet job.
I find the presentation fascinating
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Herb Rose
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Hi Phil,
In order to put a satellite into a higher orbit you must add more energy to it, to overcome gravity. The early moon losing energy due to tidal effects would not cause it to gain altitude. Keppler’s law of orbiting objects: dv^2 = C.
Herb
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Joe
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The moon is NOT organic. The moon is not round!! The moon was moved into position about 250,000 years ago to block energy from the sun. The moon is basically space station occupied by the Elohim. Elohim, the word used in the Tora for God.
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Howdy
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Elohim are the divine workers of God. Those given authority in God’s stead. Agents, facets. In any case, I believe the word is Eloheem.
Being as God itself, they need no ‘space-station’.
There are also the Neteru, or Neters.
https://www.biblicalunitarian.com/articles/jesus-christ/divine-agents-speaking-and-acting-in-gods-stead
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Alan
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I believe Joe is just trying to be cute.
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Phil
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Hi Joe,
The Royal Museums Greenwich has the moon at 4.51 Billion years old and mass: “The mass of the Moon is 7.35 x 10^22 kilograms, which means the Earth is 81 times more massive than the Moon. …” https://www.rmg.co.uk/stories/topics/moon-facts-questions
I am very curious as to how your religion established an age of 250,000 years and also the evidence of my own eyes tells me the moon only eclipses the sun occasionally.
How did you establish your perception of the moon’s origin?
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karlito
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what are the odds for the Moon to be in the distance to cover the Sun disc exactly (and add to this that it is showing only one side) by accident? 😉
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Jerry Krause
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Hi Karlito and other PSI Readers,
Karlito your questions are excellent. What you are calling attention to are termed (defined) as being coincidence. Observations with no apparent connections. But without any questions these observation exist. And you are suggesting by your two questions that one aberration might be the result of an accident, but two increases the odds that each of the two is no accident. Very, very good reasoning.
Have a good day
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Jerry Krause
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HI Karlito,
I am a scientist; therefore I am curious. So I ask: How is it you haven’t responded to my comment as I had responded to yours? I know that scientists learn new things by having discussions with other people and by reading what other people, like you, have written.
Have a good day
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Alan
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It’s a coincidence. The Sun is 400 times large than the moon and 400 times farther away. So they appear the same size. And it doesn’t exactly the Suns disk. We have total eclipses that completely cover the Sun, from seconds up to about 7 minutes. Annular eclipses in which a tiny sliver of the Sun can still be seen. Even hybrid eclipses in which the eclipse can go from total to annular.
No accident that the moon only shows us one face. It’s tidally locked. As most moons in our solar system are.
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Jerry Krause
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Hi Alan,
You concluded: “No accident that the moon only shows us one face. It’s tidally locked. As most moons in our solar system are.”
Have you, or has anyone, tried to explain in detail how it is that these planets’ satellites are “tidally locked”?
Have a good day
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James
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Tidal lock presumably is possible because the cores of moon and earth are, or were, fluid. Not because I’m aware of any arcane brake function that the system may have experienced due to core viscosity, or tidal bulge, just a first guess. It’s common to many doubles in our SS, so there’s likely a similar reason everywhere.
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MattH
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A tidal locked moon is explained by the moon having greater mass on the earth facing side than the far side.
Not necessarily gold on the near side and aerated cheese and a goose down mix on the far side but there is a/the basic concept.
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aaron
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more theories, not facts how did we get we so smart
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