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  4. Are there areas of reduced gravity on the surface of the Earth?
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Are there areas of reduced gravity on the surface of the Earth?

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Offline thedoc (OP)

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Are there areas of reduced gravity on the surface of the Earth?
« on: 15/09/2016 11:53:02 »
"joerfutureage asked the Naked Scientists:
   Hello Chris

There are spirals of less gravity than the norm on the surface of the earth.  The two I am most sure of are at Giza and in Florida.  The one in Egypt drew up the influenced area to become a plateau and the one in Florida starts at Corkscrew Marsh and formed the islands called keys.  See, the once and future osirisl.blogspot.com, and the web site: cydoniaresurrection.com.  I last appeared on the podcast: "Midnight Ocean" on the 22nd of August for the last three and a half hours of the program.  The two words that will send a conventional researcher running are pyramids and Atlantis;  Because of this I have sent over 200 emails and letters to various research organizations and have received only three replies, none of which stayed on topic and none that would look into what I have found.  Each planet has less gravity at its equator than on the rest of the body.  This becomes a weakness in the fabric of space and this is the ripple that is transmitted outward to all other planets in the area.  There is a suspect spiral that may pass through Machu Pichu, Cuzco and two other places of ancient ruins.The investigation into this will go on to tell WHY many of the ancient monuments were built.   Joe Richardson


   
What do you think?
« Last Edit: 07/11/2017 20:29:47 by chris »
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Offline jeffreyH

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #1 on: 17/09/2016 13:50:51 »
Sometime over the last year or so I watch a TV program where some guy was testing the electromagnetic field on the top of a peak and said it increased with altitude. I have no idea if he was lying or not. What actual evidence do you have? I hope I don't regret asking this. Will I?
« Last Edit: 17/09/2016 13:59:13 by jeffreyH »
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Offline jeffreyH

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #2 on: 17/09/2016 13:57:37 »
A magnetic and gravitational anomaly are documented at Bangui.

https://en.m.wikipedia.org/wiki/Bangui_magnetic_anomaly
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Offline Colin2B

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #3 on: 17/09/2016 15:08:02 »
Quote from: jeffreyH on 17/09/2016 13:50:51
What actual evidence do you have? I hope I don't regret asking this. Will I?
You might, but then you can have the pleasure of moving the thread -  which looks like an ad anyway

Joe
Can you describe how you made the measurements eg equipment used, procedure etc.
Although gravity varies over the earth's surface, no spirals have been recorded in the mapping. A spiral would be instantly noticeable on any survey but would not be strong enough to form geological structures such as the Keys. Similarly the earth's gravity field is not strong enough to cause a weakness in space - assuming you could clearly define what you mean by a weakness in space.
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Offline puppypower

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #4 on: 18/09/2016 11:55:32 »
Here is a map of the earth's gravity generated by NASA. You can find more maps if you Google; earth's gravity and GRACE (satellite).

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Offline evan_au

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #5 on: 18/09/2016 12:45:55 »
Quote from: joerfutureage
Each planet has less gravity at its equator than on the rest of the body.
I think you may be describing the effects of centrifugal force?
- A non-rotating planet far from other astronomical bodies will form a sphere.
- A rotating planet will experience a reduced force at the equator, and so will form the shape of an ellipsoid, as predicted by Isaac Newton.
- If the planet has a liquid on the surface (like Earth's oceans), they will move around until the force at the surface is equal. ie any difference due to gravity and centrifugal force is cancelled out.
See: https://en.wikipedia.org/wiki/Reference_ellipsoid

Quote
This becomes a weakness in the fabric of space and this is the ripple that is transmitted outward to all other planets in the area.
Einstein showed that the mass of the Sun and planets distorts the geometry of spacetime, and this distortion is felt by nearby planets.

The dimples in the Earth's gravitational field amount to about 0.7%; to measure them, the GRACE spacecraft orbited at an altitude of just 500km. These tiny dimples have a local effect, and will not cause a detectable difference in Earth's gravitational field at the distance of the Moon, let alone other planets.
See: https://en.wikipedia.org/wiki/Gravity_of_Earth#Variation_in_gravity_and_apparent_gravity

To generate gravitational ripples that propagate, you need some truly massive objects, like merging black holes. These generated ripples of gravitational waves that were detected in 2015 (announced early 2016).
See: https://en.wikipedia.org/wiki/First_observation_of_gravitational_waves

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There are spirals of less gravity than the norm on the surface of the earth.
Because of the way gravity works, I can understand regions of reduced or increased gravity due to differences in the density of rocks under the surface (see map posted by puppypower, above).

However, a true spiral, with an open end seems an unlikely shape on the Earth.
Propagating gravitational waves from merging black holes do form a spiral in space (but not on the surface of the black hole).

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The investigation into this will go on to tell WHY many of the ancient monuments were built.
Variations in local gravity cannot be felt by the human body.

The first modern instruments to measure gravity were invented in 1936.
https://en.wikipedia.org/wiki/Gravimetry#History

However, in principle, gravity could have been measured by comparing a pendulum clock (whose period is affected by gravity) with a spring clock (whose period is not significantly affected by gravity).

So I don't see that ancient civilisations would have known where to build gravity-seleted cities. I suspect the location was selected as being close to sources of food and water, and able to be defended against attack.

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the one in Florida starts at Corkscrew Marsh and formed the islands called keys
The sea level rose by 50-100m at the end of the last ice age.
This seems a more likely way to produce islands and marshes.
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Offline rmolnav

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #6 on: 07/11/2017 18:29:35 »
Quote from: evan_au on 18/09/2016 12:45:55
- A rotating planet will experience a reduced force at the equator, and so will form the shape of an ellipsoid, as predicted by Isaac Newton.
- If the planet has a liquid on the surface (like Earth's oceans), they will move around until the force at the surface is equal. ie any difference due to gravity and centrifugal force is cancelled out.
Right. That´s another phenomenon that shows "centrifugal force" is something quite real ... There are a lot of people out there who consider it is only an apparent or fictitious force !!
And it causes not only that deformation of ocean surface: even solid Earth has got similarly deformed (though much less) after being supporting those real centrifugal forces for billions of years ... (and initially days were much shorter, what implies much higher ω angular speed, and centripetal forces proportionally to ω²r, what in its turn also implies much higher centrifugal forces !!)
In our planet there are places even farthest from Earth C.G. than mount Everest, due to that: some Peruvian Andes peaks (note that standard altitude is relative to sea level at same paralell), as they are closer to the equator, have a higher kind of "absolute" altitude !! 
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Offline rmolnav

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Re: Are there areas of reduced gravity on the surface of the Earth?
« Reply #7 on: 09/11/2017 11:20:31 »
Quote from: thedoc on 15/09/2016 11:53:02
There are spirals of less gravity than the norm on the surface of the earth.
If the question refers not to total gravity pull, but to "apparent" gravity (what somehow makes sea surface shape), what follows could be an answer (also total pull varies in some cases).
Some two and a half years ago I posted something (#39 in  https://www.thenakedscientists.com/forum/index.php?topic=49715.0 )
that could also be here:
"Nature is far more complex than what seems at first sight. Ocean surface shape depends on not just a few physical phenomena.
I´ll try and list what, as far as I know, affects it, in a decreasing order of importance. I hope not to forget anything. If any disagreement, please let me know, and we can discuss the issue.
1) Gravity from earth itself. If our planet is considered alone, without any movement, without any other celestial object gravitationally affecting it, etc, sea surface “should" be spherical …
2) I say “should” because that is only in theory: gravity is not uniform over sea surface, because amount and density of inside material varies …
That produces sea local level differences much much bigger than tidal differences (very curious phenomena included, such as what happens around Antarctic, where water experiences a "negative" gravity, due to those massive amounts of ice at a higher altitude …) 
3) Let us “allow” earth daily rotation … Due to centrifugal forces, equator diameter gets bigger than distance from pole to pole.
4) If we now include moon/earth rotation, then we have main part of tides, which we have been discussing. We shouldn´t forget that local conditions (mainly size and shape of continents) produce changes on “theoretical” tides, because water is not completely free to “obey” the forces we have been discussing.
5) Now earth translation (actually rotation around the sun): it produces tides similar to moon related ones, but smaller. These don´t change with the clock. For similar reasons to lunar tides, a high tide happens “bellow” the sun, at noon, and another at antipodes, at midnight. Also with a certain gap due to the fact that the water bulges cannot catch up with their theoretical position …
Needless to say that when lunar tides syncronize with sun ones, we have the strongest actual tides. This happens when full and new moons.
6) Meteorological conditions also affect: atmospheric pressure, winds, etc.
7) I haven´t mentioned water temperature, as if it did´t change with space and time … That isn´t actually so, and the result is that some additional, but relatively small changes happen.
An additional curiosity in this respect. Local increase in temperatures of ocean upper part (f.e., at El Niño zone) are beeing detected thanks to “gravitational” Physics … The temperature increase produces there tiny bulges that are detected with sophisticated satellites (f.e., GRACE, a couple of satellites), thanks to very, very tiny changes in the distance to each other, derived from gravitational changes.
The software they use must be “unbelievable”: how can they tell apart the many different gravitational existing factors?
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