Gravity and our expanding Earth

[ovyyus]

http://en.wikipedia.org/wiki/Expanding_Earth

The primary objections to an expanding Earth are... the fact that the Earth's radius is not measured to be increasing today...

[rlortie]

Now for my 2 cents!

Just like energy matter cannot be created nor destroyed, just change form. See: The Law of Conservation of Mass

The earth is growing because the sun is radiating energy on it. this energy grows matter or mass in the form of vegetation. Each year when the leaves and annual plants die the matter is added to the mass of the earth.

This theory comes from the fact that a lost heavy coin over a period of years will be buried by gravity in the less dense turf that it is building up annually.

Ralph

[ovyyus]

The earth is growing because the sun is radiating energy on it. this energy grows matter or mass in the form of vegetation...

Ralph, isn't vegetation growth a reorganizing of already present matter? The Suns energy might not create or destroy matter on Earth, but it sure can move it around.

[rlortie]

Photosynthesis, the process by which chlorophyll-containing organisms-green plants, algae, and some bacteria-capture energy in the form of light and convert it to chemical energy. Virtually all the energy available for life in the earth's biosphere-the zone in which life can exist-is made available through photosynthesis.
A quite generalized, unbalanced chemical equation for photosynthesis is

CO2 + 2H2A + light energy ± (CH2) + H2O + H2A

The formula H2A represents a compound that can be oxidized, that is, from which electrons can be removed; CO2 is carbon dioxide; and CH2 is a generalization for the hydrocarbons incorporated by the growing organism. In the vast majority of photosynthetic organisms-that is, algae and green plants-H2A is water (H2O); in some photosynthetic bacteria, however, H2A is hydrogen sulfide (H2S). Photosynthesis involving water is the most important and best understood and, therefore, will be discussed here in detail.
Photosynthesis consists of two stages: a series of light-dependent reactions that are temperature independent And a series of temperature-dependent reactions that are light independent. The rate of the first series, called the light reaction, can be increased by increasing light intensity (within certain limits) but not by increasing temperature. In the second series, called the dark reaction, the rate can be increased by increasing temperature (within certain limits) but not by increasing light intensity.
Light Reaction
The first step in photosynthesis is the absorption of light by pigments. Chlorophyll is the most important of these because it is essential for the process. It captures light energy in the violet and red portions of the spectrum and transforms it into chemical energy through a series of reactions.

Also consider the building of coral reefs which relies on energy from the sun



"Photosynthesis," Microsoft(R) Encarta(R) 97 Encyclopedia. (c) 1993-1996 Microsoft Corporation. All rights reserved.

[John Collins]

If moon and the earth're both expanding then their increasing masses must be more attractive and they should be closing the gap?

JC

[DrWhat]

Exactly John. And even if their masses weren't changing at all why doesn't the moon slowly get closer to earth, and eventually crash into it due to gravity?

[ovyyus]

...why doesn't the moon slowly get closer to earth, and eventually crash into it due to gravity?

http://www.cs.dartmouth.edu/farid/scien ... avity.html

Gravity is also the reason why the moon (and satellites) orbit the earth and why we orbit the sun. But then why doesn't the moon crash into the earth? The moon is, in fact, constantly falling towards earth, it is just that it keeps missing. With an initial motion along the path of the orbit, the moon can continually fall towards earth without ever reaching it. This is illustrated on the right in the above diagram, where a cannon is shown firing a cannonball. If the speed of the cannonball is too slow it will crash into the earth. If the speed is too fast, the cannonball will escape the gravitational attraction of the earth. But, if the speed is just right, then the cannon ball will continually fall towards the earth, but never reach it -- it will orbit the earth.

Relative stability of the earth/moon orbit might suggest relative stability of system gravity/mass/momentum?

[John Collins]

If the moon is moving away from the earth and has been for millions of years it must have been much closer at one time and that would mean it had a greater gravitational effect on the earth and its inhabitants in, say, the dinosaur age.

JC

[docfeelsgood]

it is generally accepted fact among metal detectorists that things dissapear into the earth at about 1/8 inch per year . this is because the plants draw minerals etc from deep in the ground and die leaving the residual on the surface .

[Fletcher]

John .. in the time of the dinosaurs the moon was considerably closer to earth & very large in the sky by todays standards - it is just coincidence that the the moon & sun present a similar area as seen from earth today which allows an almost perfect eclipse - this wasn't always so - the moon is very slowly increasing its average orbit by about 4cm per year IIRC [close to Damian's figures] - given enough time the moon will decrease in size as we view it as its orbit increases, assuming mankind is still around then.

The accepted theory about the large sizes of the dinosaurs is that ice & rock analysis of isotopes etc shows that oxygen content was as high as 26% of the atmosphere compared to around 18% today - this meant that animals & insects etc could grow considerably larger in that environment.

If the mass of the earth were increasing then might we not expect to see a compensatory effect in the earths velocity as momentum is conserved - although the average day length is getting longer IIRC I don't believe that an average year is getting longer or less ?

[triplock]

Although it maybe a simplistic view, I believe that everything around us is just a re-constitution of matter that has always existed since earth's creation. With the exception of the odd meteorite adding to this melting pot, earth's mass has remained constant.

IMHO, I don't believe in any expansionist theories.

Chris

[John Collins]

I saw an estimate that somewhere between 1 and 10 billion kilograms (1-10 million tonnes) of matter probably fall to Earth each year, in the form of meteors, matter from the solar wind, microscopic dust particles etc.

I don't know how much that works out at over millions of years but it seems to be enough to explain an increase in earth's mass.

JC

[ribby55]

Lets see now the dinosaurs have been here for millions maybe billions of years. The earth was a hostile place for humanoids. We wouldn't last a minute without being snached up by some giant creature. The theory is a meteor hit the earth and killed off all the larger dinosaurs. And we somehow managed to take over the planet. Hmmm. We have been around for only a blip of time in the whole context of things. Could it be possible that something else besides a meteor collision could have changed the face of the earth? Could it be that a race much more advanced then us came here and genetically altered the DNA so that it could create an enviroment that could support our bi-ped existence? I believe we did not evolve without some kind of outside intervention. And given enough time, if we don't destroy ourselves we our own arrogence first, we will eventually travel and possibly plant the seed of our own DNA on another otherwise uncivilized planet. So expanding earth theory and extra-terrestrial intervention. Things that are not taught in school. Let's just say that they are so superior to us that we can't even see them. They can move through space and time without our knowledge. They can move so fast that we are lucky to even get a glimpse of them. In ancient times we could not understand an advance culture so we could understand the terms the they were Gods. Hence the begginings of religion. Everything is energy and we are all a part of it.

Food for thought...

[Jim Williams]

The moon is moving away from Earth due to an increase in its orbital speed. This speed increase is due to an angular momentum generated by the relationship between the moon and Earth. The result is Earth's rotation is slowing down, while the moon's orbital speed is increasing. Eventually the Earth and the moon will face each other, as the moon faces the Earth now. Can't remember my source. Wikipedia or something.

Suns (and supernovae) generate the matter found in planets. Isn't possible that an overall increase in matter is due to an imbalance in E=MC^2 in which stars generate more matter than they are using energy? That would still add up to an ever inceasing expanding universe but static planets.

[KAS]

If all matter in the universe is expanding at the same rate, then nothing would be measurable.
We could be expanding at a colossal rate and never know it.

If we weigh a 1lb weight at mid day then weigh it again at mid day the following day, its weight would not have changed. It could be that all matter, including the micro matter that makes up the scales has also expanded at the same rate, resulting in a reading that has not changed.

I'm begining to like this theory.

Kas