# Effects of Human Weight on Earth

Discussion in 'Earth Science' started by Thoreau, Feb 24, 2010.

1. ### ThoreauOIF Veteran 2003-2011Valued Senior Member

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With the drastic increase in the human population over many years, I was wondering if our weight has any effects on the planet such as it's rotation, gravity, etc.

2. ### AsguardKiss my dark sideValued Senior Member

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how could the mass of humans have any impact on the total mass of the world? Every human is made up of mass which was ALREADY on earth, the only imputs are energy which will still be in the system anyway, humans use it they dont create it

Last edited by a moderator: Feb 25, 2010

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No, not really. Even Asguard got something right for a change - people ARE made from the "contents" of the Earth - so there's no net gain there. It doesn't matter if it's trees, people or just rock and water, the net weight remains the same.

However, there IS on thing that actually does change the weight (mass, actually) of the Earth - the tons of space dust and meteorites that rain down on it each year. But when compared to the mass of the Earth, the effects are FAR too small to even be measured.

4. ### James RJust this guy, you know?Administrator

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The weight of human beings doesn't come from nowhere. It comes from the food we eat, the water we drink etc. And all those raw materials were already on the planet before we were born.

5. ### TrippyALEA IACTA ESTModerator

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Mod Note:
Posts removed/edited for unneccessary content (flamin, trolling, responding to flaming and trolling etc).

This is my one and only warning on the matter.

Meanwhile, to address the question of the original post, as been pointed out, for the purposes of this question, the earth is a closed system, and mass conservation applies.

Humans don't change the total mass of the planet, just where some of it is concentrated.

6. ### jmpetValued Senior Member

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The Earth is defiantly getting larger, massier and heavier over time. Thousands of tons of interstellar dust falls on the Earth daily. And let's not forget that the sun's rays also makes the Earth heavier (for example, petrified trees).

Neal Adams has a compelling, albeit somewhat off view of the universe worth mentioning. He supposes the Earth was smaller than the moon a billion years ago and grew to its present size over time. There's geological gray areas that point to that theory but there is no foundation of science to back his claims up.

If anyone's interested:

Clip #0 sums it up.

7. ### TrippyALEA IACTA ESTModerator

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Neal Adams should have stuck to writing comic books, his is trivially disproven junk science with no physical evidence to back it up.

8. ### jmpetValued Senior Member

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Wow Trippy- it took you a full two minutes to debunk that whole site- you're a genius.

9. ### TrippyALEA IACTA ESTModerator

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Actually, if you took the time to look around, you'd see that I have discussed Neal Adam's work extensively, I've spent substantially more than two minutes looking into his work which amounts to little more than "No part of the oceanic crust which is more than about 600 180 million years old, therefore 600 180 million years there were no oceans and the earth was smaller" while completely ignoring things like Billion+ year old ophiolite sequences, and the fact that according to tidal rythmite data there has been no secular change in the earths rotation about it's access, the moons orbit about the earth, or the length of the year, beyond that implied by tidal braking of the earth by the moon (conservation of angular momentum predicts that if the earth was as small as Adams claims then it should have been spinning a lot faster).

Last edited: Feb 25, 2010
10. ### jmpetValued Senior Member

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Excellent. I am silenced.

Still fun stuff to watch tho...

I don't mind bad science as long as it's entertaining. The Velikovsky Principle.

11. ### TrippyALEA IACTA ESTModerator

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Axis, not access :facepalm:

12. ### Uno HooRegistered Senior Member

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Every now and then geologists report that they track minute changes in Earth rotation in sync with rush hour traffic in large metropolitan areas. Changes in planet angular momentum.

Or was it astronomers? I'm not going to worry about it. Look it up if you are curious enough.

13. ### SyzygysAs a mother, I am telling youValued Senior Member

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I was wondering the same, but in a way that the question is not limited to humans:

Not counting space dust and such, does the Earth's mass change and in what way over time?

You see for those who says animals eat and exchange their weight for already existing things, what about plans? They use photosynthesis and air beside water and they keep growing. What once was a hot rock now it is jungle and such, so I would say that the mass is growing...

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If you discount all the space debris, then no - it's not changing.

Think about it for just a moment. Every living thing - people, trees, grass, whatever - are made from chemicals that CAME from the Earth. Carbon, nitrogen, potassium, etc. were already here. It doesn't matter if they are still in chemical form OR as part of living matter - how could there possibly be more of those chemicals just because some of them have been incorporated into living things??

Again, if you choose not to count the space debris at all, then the Earth is a closed system - nothing is being added - so how could there ever be more than what was here to start with?

15. ### Uno HooRegistered Senior Member

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Is more energy absorbed from space than is radiated out?

Is energy regarded as mass by any branch of non crank science?

16. ### AlphaNumericFully ionizedModerator

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The energy would represent a tiny increase compared to the matter itself. If a ton of TNT fell to Earth from space it would contain $4 \times 10^{9}$ Joules of explosive energy due to its chemical bonds and that is about $\frac{40}\frac{3c} \sim 4 \times 10^{-8}$ kilogram worth of energy. The matter is about a trillion times more massive.

A rock falling to Earth increases the Earth's mass because its a rock, not because its energetic. You might want to check out that 'non crank science'. It's science for a reason.

17. ### SyzygysAs a mother, I am telling youValued Senior Member

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I am not so sure. Sunshine for example. It is weightless, doesn't add to the mass of Earth but it makes plants to grow bigger, thus it can increase the overall mass. Unless you are saying that plants are just water what was already here before they grew...

Or if you say that all plants eventually rot thus became a non-weight what is the deal with petrified trees?

18. ### SyzygysAs a mother, I am telling youValued Senior Member

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Researching the problem here is the answer to the original question about humans' weight:

The answer is that no it doesn't add to the mass of the Earth.

My problem is with the Sun's energy. At the end of the article:

"Matter can be changed to energy, and vice versa. It doesn't happen much on Earth, but the massive amount of energy coming out of our Sun actually represents a gradual decrease in the Sun's mass. "

So the Sun's radiating its energy out. The Earth in this regard can not be viewed as a closed system, because it receives energy from the Sun. And in my view that energy during photosynthesis transfers to be mass and increases Earth's mass....

19. ### IKNOWEVERYTHINGRegistered Member

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weight of the world

If the world is not increasing in weight then what about the concentration of that weight in a specific area/country.

Would that affect the earth's rotation/gravity pull/whatever else?

My thought is this... if you have a ceiling fan spinning at full speed with four fixed blades it will spin completely fine. Once you remove just one blade and perhaps even add it to another blade that fan will violently spin out of control. So, hypothetically... if everyone in America were to move to China what affect would that have on our world (besides of course the obvious difficulties of so many people inhabiting one single area)?

20. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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Rather strange to pick that user name and then ask such a simple question...
http://hypertextbook.com/facts/2006/DanielTouger.shtml

The total mass of humans on Earth has less effect on its rotation than than a fly does on a ceiling fan: it's an insignificant percentage.