What can the GRACE Gravity Model 01 reveal about Earth's gravity field?

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Discussion Overview

The discussion revolves around the GRACE Gravity Model 01 and its implications for understanding Earth's gravity field, as well as related topics such as elemental distribution on the Moon and the origins of elements through supernovae. Participants explore the model's accuracy and its potential impact on various scientific fields, including oceanography and climate science.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants highlight that the GRACE Gravity Model 01 represents a significant advancement in measuring Earth's gravity field, claiming it is 10 to 50 times more accurate than previous models.
  • There are discussions about the elemental distribution on the Moon, particularly the higher concentrations of iron and titanium on the nearside, with references to data from the Clementine mission.
  • One participant questions whether the concentration of iron on the Moon's nearside could be influenced by Earth's magnetic field during the Moon's formation.
  • Another participant suggests that the migration of elements through liquid magma under gravity is a more plausible explanation for the distribution of iron on the Moon.
  • There are references to the binding energy of elements and their relevance to processes like fission and fusion, with some participants discussing the implications for supernovae and the origins of elements in the universe.
  • Some participants express skepticism about the need for exotic explanations regarding the Moon's origin, favoring the glancing collision theory as the dominant view.
  • One participant speculates about the possibility of the iron concentrations on the Moon mimicking the shape of the ancient supercontinent Pangea.

Areas of Agreement / Disagreement

Participants exhibit a mix of agreement and disagreement. While there is some consensus on the significance of the GRACE model and the glancing collision theory for the Moon's origin, multiple competing views exist regarding the processes affecting elemental distribution and the implications of binding energy.

Contextual Notes

Participants note that discussions about the origins of elements and their distribution are complex and may depend on various assumptions and definitions. The relationship between gravity, elemental migration, and the Moon's formation remains unresolved.

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ggm01.jpg
This is an animation of the GRACE Gravity Model 01 which was released in July of 2003. This model is based upon preliminary data provided by the GRACE mission. The release of this preliminary model is a major advancement for oceanographers and a taste of scientific advancements yet to come from GRACE. Improved weather and climate change predictions now result from this model of Earth's gravity field 10 to 50 times more accurate than previous models

http://www.csr.utexas.edu/grace/gallery/animations/ggm01/index.html

What does this model tell us?
 
Astronomy news on Phys.org
Or Maybe with the Moon

Why Iron?

http://physicsweb.org/objects/world/12/7/8/pw-12-7-8fig2.jpg
Clementine measured the abundance of (a) iron oxide and (b) titanium dioxide on both the nearside and farside of the Moon. The scale bar indicates the percentage-by-weight values, the highest concentration is shown in red and the lowest is in blue. Note the higher abundance of both iron oxide and titanium dioxide in the smooth plains, known as maria, on the nearside.

http://physicsweb.org/box/world/12/7/8/pw-12-7-8fig2

Gamma-ray spectrometer (GRS). Gamma rays are produced on the lunar surface through the decay of radioactive isotopes, and via the bombardment of the surface by high-energy cosmic rays. Since the energy of the resulting gamma ray is characteristic of its parent element, the GRS can map the lunar distribution of these elements
 
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One has to become accustom to how we percieve Window on the Universe.

http://swift.gsfc.nasa.gov/Images/swift/Swift.jpg

The Swift Gamma-Ray Burst Mission (Scheduled launch: October 7, 2004)

Gamma-ray bursts (GRBs) are the most powerful explosions the Universe has seen since the Big Bang. They occur approximately once per day and are brief, but intense, flashes of gamma radiation. They come from all different directions of the sky and last from a few milliseconds to a few hundred seconds. So far scientists do not know what causes them. Do they signal the birth of a black hole in a massive stellar explosion? Are they the product of the collision of two neutron stars? Or is it some other exotic phenomenon that causes these bursts?

With Swift, scientists will now have a tool dedicated to answering these questions and solving the gamma-ray burst mystery. Its three instruments will give scientists the ability to scrutinize gamma-ray bursts like never before. Within seconds of detecting a burst, Swift will relay a burst's location to ground stations, allowing both ground-based and space-based telescopes around the world the opportunity to observe the burst's afterglow.

Swift, a NASA mission with international participation, is scheduled for launch on October 7, 2004.

http://swift.gsfc.nasa.gov/docs/swift/swiftsc.html

http://www.cmf.nrl.navy.mil/clementine/gif/clem.1.gif

Clementine

Gamma-ray spectrometer (GRS). Gamma rays are produced on the lunar surface through the decay of radioactive isotopes, and via the bombardment of the surface by high-energy cosmic rays. Since the energy of the resulting gamma ray is characteristic of its parent element, the GRS can map the lunar distribution of these elements

http://physicsweb.org/box/world/12/7/8/pw-12-7-8box1

If we take in the theoretical views of what is on the horizon in terms of our research predictions, they must follow some predetermined framework.

The elemental response then to early universe formation asks us to consider the phase changes from the Planck Epoch, through Grand Unification and standard models arise from this. This leading perspective then asks us how we shall see this most outer boundary of these shells, and if current day elemental consideration are self evident in the matters around us, then how shall we percieve this in the early universe?
 
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kuenmao said:
If you look at the graph of binding energy per nulceon against atomic number, you'll realize that elements around the position of iron have the highest binding energy. Fission occurs only in elements which have an atomic number much larger than iron(ie. uranium), and fusion occurs in elements with a smaller atomic number compared to iron(i.e. hydrogen). Both extract energy through converting part of their mass into energy.


http://physicsweb.org/objects/world/12/7/8/pw-12-7-8fig2.jpg

I am looking at this in context of post on moon(cooling) and its elemental distribution as it did so? What is the age of the moon? Is it older then earth?

The two basic types of supernovas are Type Ia and Type II. Other types, such as Types Ib and Ic, are unusual supernovas that have most of the properties of type II supernovas.

Type Ia are believed to be triggered by a large transfer of mass from a companion star onto a white dwarf that pushes the white dwarf over the Chandrasekhar limit. A thermonuclear explosion follows, blowing the entire star apart, and sending material rich in iron and other products of the explosion rushing out into space. Since a white dwarf is involved, Type Ia supernovas are expected to be found among old star systems, such as globular clusters, the central bulges of galaxies and elliptical galaxies.


Type II supernovas are thought to result from the collapse of a massive star (ten or more times as massive as the Sun) that has reached the end of the red giant stage of evolution, and formed an iron core. The core collapses under the weight of the outer layers of the star. A neutron star is formed, lots of neutrinos and other radiation is emitted, and everything except the neutron star is blown away. Since massive stars are involved, Type II supernovas are found in the spiral arms and other star-forming regions of spiral and disk galaxies, which have lots of gas and dust for the formation of new stars.

http://chandra.harvard.edu/resources/faq/sources/snr/snr-14.html

Live and learn eh?

If strings can congregate in the black hole, and the black hole contracts, what can happen with the energy? Can it become very hot?

Thought I would continue posting here, as they intend to axe this section of the forum. I think I can save the moderators some work.
 
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The binding energy is pretty irrelevant to the elemental distribution in planets (and the Moon). These processes proceed by chemical interactions, not nuclear ones. The present ideas of the origin of the Moon, from a glancing collision of the early Earth with another body, are pretty consistent, if not absolutely dominant. Looking for an exotic origin, looks like a futile task.

As to the supernova production of the elements, that is something that affected the whole primeval cloud, not just the earth-mooon system. The heavier elements drifted to the inner cloud (lower gravitic potential), so the inner planets, Mercury, Venus, Earth-Moon, and Mars, and the asteroids, are richer in iron and heavy elements than the ourter planets.
 
Would the Iron on the near side of the moon, be concentrated there, because of the attraction between Earths magnetism, and the Iron that was there when the moon coalesced into an orb, from a fragmented state?
 
I doubt it. Migration through the liquid magma unde gravity toward the common center of gravity would seem more likely. And remember the Moon was much closer to the Earth in the remote past.
 
That is such an interesting image of the iron concentrations on the moon. Is it possible that it mimics what would have been the shape of Pangea, the old super continent?
 
http://www.bbc.co.uk/nature/reallywild/amazing/images/peacock2.jpg

Self Adjoint said:
As to the supernova production of the elements, that is something that affected the whole primeval cloud, not just the earth-mooon system. The heavier elements drifted to the inner cloud (lower gravitic potential), so the inner planets, Mercury, Venus, Earth-Moon, and Mars, and the asteroids, are richer in iron and heavy elements than the ourter planets.

See you capture the thnking in terms of shells. I mean certainly, weak gravitational interaction at a level that has manifested into today's view of the solid balls. From the Planck epoch to today

But really if we are to arrive at any exploded view of the standard model arising from a supersymmetrical world( consider a tree fractal that has a base signature to it), and all the time, it looks quite different when it has traversed from a beginning, as a evolution of design.

So we call it a string? Quantumly and cosmologically? From a one dimensional perspective, it contained gravity.

So I look at the moon, and I see it's layers, and the stratification like shells. It made sense in this cosmological scenario, did Chandra see more?
 
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It's not just seeing, it's understanding. They can draw amazing conclusions from the CMB because it's just radiation and since the 19th century they've learned more and more about radiation. So when they draw conclusions about inflation, or big-bang nucleosynthesis they are on sound ground. By contrast, nobody has more than a speculative idea of how the iron layers of the Moon got distributed the way they are, and generic thinking about shells or "limnocentric structures" doesn't add specific undrstanding.