Question Earth Moon Origin

[billslugg]

The impact did not make the Moon. The impact made a cloud of molten material all around the Earth. Most of it flew off into space. Some of it settled into a circular orbit and then made the Moon over many millions of years. I am open to a better explanation but it must account for the iron deficit and must account for the high amount of angular momentum in the resultant system.

 

[Classical Motion]

Pouring the slag out of the cradle.

 

[Harry Costas]

Hello Billslugg

That is a catch 22
When we get more details of the moon from core to the crust.
Maybe then we are, maybe able to conclude the origin

 

[Harry Costas]

My thoughts on the origin of the moon.
I have the opinion that the Earth and the planets and their moons evolved about the same time from our Sun going Supernova releasing the solar envelope in the form of an hourglass.
Collision during the early years is possible and fragments may have added to the moon that was in a stable motion.
Research is needed to discover the unknown.

[Submitted on 2 Jun 2024]

Lunar antineutrinos and heat: Fluxes from primordial radioactivity​

Steve Dye, Andrew Barna

We present estimates for the fluxes of heat and antineutrinos due to primordial radioactivity within the moon. We use a radial density profile, specifying an inner core and a model-averaged crust. The 1∘ by 1∘ gridded crust data draw on global maps from spacecraft missions. Thickness, density, and elevation come from measurements of the gravitational field. Thorium, uranium, and potassium abundances come from measurements of the gamma ray intensity. Assuming no vertical variation of the crustal abundances predicts 302 GW of radiogenic heating. Accepting a heat flux of 5 mWm−2 from the mantle plus low viscosity zone both with Th/U≃3.7 and K/U≃2000 tallies an additional 185 GW of radiogenic heating. The corresponding antineutrino fluxes from the average crust and the mantle plus low viscosity zone are 2.02×106 cm−2s−1 and 6.40×105 cm−2s−1, respectively. Subsurface variations of thorium, uranium, and potassium abundances in the crust are a potentially large and not yet assessed source of uncertainty. The uncertainties reported with the radial density profile contribute ±1.4×103 cm−2s−1 and ±0.6 GW (<1\%) to the estimates of antineutrino flux and radiogenic heating, respectively, from the mantle plus low viscosity zone.

 

[Deleted member 1146189]

If the Earth and Moon were formed from the same disc they would share the same constituents. The Moon lacks the large amount of iron we have here on Earth.

There are 3 main types of meteorites - 1) mainly silicate, 2) silicate, iron and nickel, and 3) iron and nickel. If the moon started to form from the same disc, after the earth started to form, and after iron and nickel elements had been partially left behind, might that start to explain the disparity?

 

[billslugg]

If the Earth and the Moon formed at the same time from the same disc they would have the same elements. Differentiation does not occur during synthesis, it occurs after the molten bodies form.

 

[Deleted member 1146189]

If the Earth and the Moon formed at the same time from the same disc they would have the same elements. Differentiation does not occur during synthesis, it occurs after the molten bodies form.

IF the accretion disc was hot, and cooling, molten bodies of iron and nickel would condense whilst the silicates were still gaseous, so if the moon started to form say, 100m years later, and the developing earth had by then swept up a portion of those metals mightn't that result in a volume of disc more in keeping with the moon's constituents?

 

[Harry Costas]

The theories as to the origin of the moon, still remain as theories.

[Submitted on 8 Mar 2024]

The response of the Moon to gravitational waves​

Xiaoming Bi, Jan Harms

The response of the Moon to gravitational waves (GWs) is used by some of the proposed lunar GW detectors like the Lunar Gravitational-wave Antenna (LGWA) to turn the Moon into an antenna for GWs. The deep connection between the lunar internal structure, its geophysical environment and the study of the Universe is intriguing, but given our limited understanding of the Moon today, it also makes it very difficult to predict the science potential of lunar GW detectors accurately. Lunar response models have been developed since the Apollo program, but there is evidence coming from seismic measurements during the Apollo missions that the models are not good enough and possibly underestimating the lunar GW response especially in the decihertz frequency band. In this paper, we will provide an extension of Freeman Dyson's half-space model to include horizontally layered geologies, which allows us to carry out computationally efficient calculations of the lunar GW response above 0.1\,Hz compared to the normal-mode simulations used in the past. We analyze how the results depend on the values of geometric and elastic parameters of the layered geological model, and we find that modifications of the geological model as required to explain Apollo seismic observations can boost the lunar GW response.

 

[billslugg]

Iron might condense first but only as dust. It would not form large pieces in space, given that it is condensing out of a gas containing many elements. Nothing forms in space but for very fine dust. It is a well mixed cloud of many different elements. Only after forming a molten ball with enough mass to allow for its own gravity to do the separation. Separation can only occur inside large molten bodies like planets.
First form the Earth. Let its large size allow for gravity to separate out the various elements. Then break off a large chunk of the outer silicate layer to form the Moon.
No other process can explain it.

 

[Deleted member 1146189]

Thank you for your replies.
Partial separation/sorting might occur in the accretion disc at temperatures where the nickel and iron are liquids and silicates are gaseous. Similar liquids naturally coalesce given proximity - the earth has a nickel/iron core. The 3 main types of meteorites imply bodies forming in volumes of the disc with different % constituents, and at different times/temps maybe, imo. Dusts are solids and form at lower temperatures, ie later. What is the initial gravitational impetus that could draw this dust together to form the earth?

 

[Helio]

An excellent book on this topic is “When the Earth had Two Moons”. The strong evidence showing a close match between Earth's outer surface and the Moon, as Bill mentions, helped advance the Impact Theory from mere conjecture. But the material differences between the near and far side required a modification to the theory. A second moon forming after impact, per this hypothesis, would eventually merge with the main body in a gentle enough way to explain much of what is observed.

 

[Harry Costas]

Stars do go through cycles releasing their solar envelope.
Particularly when the solar system passes through a Nebulae absorbing matter that may take a billion years of chaos.

If you dance with another body in uniform motion, then the origin maybe the same or maybe not.

just thinking aloud

 

[Adel]

The scientific and geological explanation for the existence of the lunar seas is what will reveal the origin of the moon because meteorites and asteroids are not the reason for the existence of the lunar seas and new scientific facts will emerge regarding the lunar seas.

 

[billslugg]

The lunar seas are most likely lava floods. As the molten Moon cooled the outer surface got solid and shrunk. Giant cracks formed. Magma shot out of the cracks and flooded the whole area.

 

[Harry Costas]

More research is required to understand the origin of the moon

[Submitted on 15 Aug 2024]

Lunar Swirls Unveil the Origin of the Moon Magnetic Field​

Boxin Zuo, Xiangyun Hu, Lizhe Wang, Yi Cai, Mason Andrew Kass

The origins of the lunar magnetic anomalies and swirls have long puzzled scientists.The prevailing theory posits that an ancient lunar dynamo core field magnetized extralunar meteoritic materials, leading to the current remnant magnetic anomalies that shield against solar wind ions, thereby contributing to the formation of lunar swirls. Our research reveals that these lunar swirls are the result of ancient electrical currents that traversed the Moon's surface, generating powerful magnetizing fields impacting both native lunar rocks and extralunar projectile materials. We have reconstructed 3-D distribution maps of these ancient subsurface currents and developed coupling models of magnetic and electric fields that take into account the subsurface density in the prominent lunar maria and basins. Our simulations suggest these ancient currents could have reached density up to 13 A/m2, with surface magnetizing field as strong as 469 {\mu}T. We propose that these intense electrical current discharges in the crust originate from ancient interior dynamo activity.

 

[Harry Costas]

In my opinion looking at the structure of the moon, similar to the Earth.

They have a molten outer core mantle and crust.
During the formation of the solar system, as a result of maybe from our Sun ejecting the solar envelope or during chaos going through a Nebulae.

Both the Earth and the Moon danced in the same area.

 

[Harry Costas]

Structure of the moon

structure of the moon - Google Suche

 

[Harry Costas]

If the Erath and the Moon kissed there would have been an irregular motion that would eventually result in a collision.

 

[Harry Costas]

During the probable kiss
Over 5 billion years ago.
Too hot to handle