# Does matter accumulate in Earth's gravity well?

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TimeSkip
I would like to understand if matter accumulates into the gravity well of the Earth?

After so many years of circling the sun I have this imagination of tritium, nitrogen, and ozone accumulating underneath the Earth into it's traditional orbit, and accumulating over time.

Is this possible and if so, is there anything we should be worried about in terms of gravity waves confronting this matter accumulated over time there?

Gold Member
I would like to understand if matter accumulates into the gravity well of the Earth?

Well, yes. Gas dust and meteors are continually bombarding Earth.
Amongst other things, you see meteors and shooting stars streaking across the night sky, and you see the solar wind in the Aurorae, and we are constantly sweeping up gas and dust in our orbit.

Many tonnes of material fall to Earth every year.

Note, BTW that Earth loses a lot of matter too (mostly H and He escaping the atmo).

Calculations suggest that Earth actually loses more matter than it gains (~ 50,000 tonnes per year).

After so many years of circling the sun I have this imagination of tritium, nitrogen, and ozone accumulating underneath the Earth into it's traditional orbit, and accumulating over time.
"Underneath"?

Yes, Earth accumulates matter on its surface as well as in orbit, and there is even matter in Earth's orbit around the Sun, as well as on Earth-crossing paths.

Is this possible and if so, is there anything we should be worried about in terms of gravity waves confronting this matter accumulated over time there?
Well, the short answer is no, but why do you think there might be? What would gravitational** waves have to do with it?

** did you mean gravity waves or gravitational waves? They're very different things.

https://en.wikipedia.org/wiki/Gravitational_wave
https://en.wikipedia.org/wiki/Gravity_wave

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Dragrath, russ_watters, Klystron and 1 other person
TimeSkip
"Underneath"?

Yes, Earth accumulates matter on its surface as well as in orbit, and there is even matter in Earth's orbit around the Sun, as well as on Earth-crossing paths.
Yes, I think I meant inside the gravity well of the Earth. Is that unclear? I suspect gases and matter are inside it as it traverses around the sun.

Gold Member
I suspect gases and matter are inside it as it traverses around the sun.
Certainly. There is no clear boundary between Earth's local space and interplanetary space. What is your concern again?

TimeSkip
Certainly. There is no clear boundary between Earth's local space and interplanetary space. What is your concern again?
Isn't this worrisome? I suspect that we have significant amounts of highly enriched hydrogen to tritium over the millennia of years of the Earth orbiting the sun. What kind of effects would all this enriched material in the gravity well of the Earth have on the sun possibly if it at all does?

Gold Member
Isn't this worrisome? I suspect that we have significant amounts of highly enriched hydrogen to tritium
Shouldn't you be just as worried about the tonnes and tonnes of uranium, plutonium and other highly radioactive materials already on/in Earth?

Did you know that the reason the Earth's core is still molten (as opposed to cold and dead, like the Moon or Mars) is due to heat from radioactive decay of elements? That's a lot of radioactive material right under our feet. Way more than what you mention.

2022 Award
I suspect that we have significant amounts of highly enriched hydrogen to tritium over the millennia of years of the Earth orbiting the sun
In what sense do you mean "enriched"? That normally means a material has been filtered and refined to keep only (or at least, more of) the parts you want (just the fissile isotope of Uranium, for example). That seems to me to be the exact opposite of taking a few thousand tonnes of matter and scattering it over the surface of the Earth.

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Dragrath, russ_watters and davenn
Gold Member
Yes, I think I meant inside the gravity well of the Earth. Is that unclear? I suspect gases and matter are inside it as it traverses around the sun.

Anything caught in Earth's gravity will end up on Earth or maybe in orbit
I have never yet heard of any science confirming the accumulation of material in orbit as you seem to think happens
Therefore I think your concerns are unfounded

Gold Member
After so many years of circling the sun I have this imagination of tritium, nitrogen, and ozone accumulating underneath the Earth into it's traditional orbit, and accumulating over time.

As one other responder said ... underneath ??
I suspect your understanding of a gravity well is not quite right

Dragrath, sophiecentaur, russ_watters and 1 other person
Isn't this worrisome? I suspect that we have significant amounts of highly enriched hydrogen to tritium over the millennia of years of the Earth orbiting the sun. What kind of effects would all this enriched material in the gravity well of the Earth have on the sun possibly if it at all does?
First of all, why do you think tritium would be preferentially trapped? Second of all, tritium has a half-life of only 12 years, and so quickly decays to He-3 if it were to be trapped.

Dragrath, Keith_McClary, Vanadium 50 and 2 others
TimeSkip
I stand corrected then about tritium. For what it's worth I think that it's interesting that matter might find its way collecting in the gravity well of the Earth over millennia.

As a side question it's interesting that aurora's don't happen as often over Antarctica, whilst probably heavier matter collects in the gravity well instead.

I think there's a whole "trail" of matter around the Earth as it has traversed throughout time around the sun.

davenn
Mentor
I think there's a whole "trail" of matter around the Earth as it has traversed throughout time around the sun.
I think that's based on misunderstanding what a "gravity well" is...and also what a "planet" is.

Stray dust that wanders near Earth generally ends up on Earth.

TimeSkip
I think that's based on misunderstanding what a "gravity well" is...and also what a "planet" is.

Stray dust that wanders near Earth generally ends up on Earth.

Sorry should I have written: Gravitational potential well?

Mentor
Sorry should I have written: Gravitational potential well?
Doesn't really help explain what you think is happening/where this matter is collecting.

davenn and PeroK
TimeSkip
Doesn't really help explain what you think is happening/where this matter is collecting.
Is hydrogen, nitrogen, and water molecules simply "sitting" in it?

2022 Award
Is hydrogen, nitrogen, and water molecules simply "sitting" in it?
Everything will fall (using "fall" in a general sense that can include orbiting) until it hits something like the atmosphere or the surface of the Earth.

Staff Emeritus
Gold Member
I stand corrected then about tritium. For what it's worth I think that it's interesting that matter might find its way collecting in the gravity well of the Earth over millennia.

As a side question it's interesting that aurora's don't happen as often over Antarctica, whilst probably heavier matter collects in the gravity well instead.

I think there's a whole "trail" of matter around the Earth as it has traversed throughout time around the sun.
Maybe it will help if we address the exactly what a "gravity well" is.
Below is a representation of gravity wells, both the Sun's and the Earth's (not to scale!)

The large "dip" is the Sun's gravity well, and the Smaller dip is the Earth's, which itself is in the Sun's gravity well. Things tend to settle to the bottom of a well. Since Earth's well is a localized dip in the Sun's well, anything that gets close enough to the Earth will tend to settle to the Bottom of that dip rather than all the way to the bottom of the Sun's well. ( The Earth's surface will however get in the way causing it to settle on the Earth's surface. Anything that is far enough away from the Earth will have its path dominated by the Sun' well.
So what do you mean by stuff collecting in the Earth's gravity well? The only way for stuff to collect in the Earth's well without building up on the Surface would be for it to go into orbit around the Earth, and it isn't that easy for the Earth to collect matter around it this way.

russ_watters
Staff Emeritus
As a side question it's interesting that aurora's don't happen as often over Antarctica,

whilst probably heavier matter collects in the gravity well instead.

TimeSkip
So what do you mean by stuff collecting in the Earth's gravity well? The only way for stuff to collect in the Earth's well without building up on the Surface would be for it to go into orbit around the Earth, and it isn't that easy for the Earth to collect matter around it this way.
I only hypothesize that matter "may" accumulate in the Earth's orbit or gravity well if this makes any sense, as per the opening post question in the OP.

However, I am unsure if this is true. I suspect that the gravitational potential well is what contributes to this effect as more massive matter accumulates there possibly. I also, and interested if this has been modeled recently or so over time or even documented or debunked?

These are just basic assumptions about what may reside there. I'm not sure if any of this is true.

My further hypothesis is that due to this the nature of aurora borealis and aurora australis might be different.

I don't know much of what happens in below or "above" Antarctica.

davenn
TimeSkip
Unfortunately, I just did a search and could not find anything of significate to that assertion. So, I take it back, but am interested if it is true or not in your or other's opinion.

Gold Member
am interested if it is true
Remember "observer bias".
How many aurora australis go unobserved because no denizens of the sparsely populated southern latitudes happen to be looking up?

TimeSkip
It might be a small matter of documented spectrographic analysis of the australis auroras in comparison to the borealis to determine any truth to the assertion that there's any different matter orbiting around Antarctica vs. Artic Circle.

davenn
Staff Emeritus
It might be a small matter of documented spectrographic analysis

If you don't have one, may I politely suggest you stop making stuff up and asking us to explain it? People get real tired of this game real fast.

Dragrath and russ_watters
TimeSkip

If you don't have one, may I politely suggest you stop making stuff up and asking us to explain it? People get real tired of this game real fast.
I'll be vigilant about that from now on. Thanks.

Homework Helper
Gold Member
2022 Award
However, I am unsure if this is true. I suspect that the gravitational potential well is what contributes to this effect as more massive matter accumulates there possibly. I also, and interested if this has been modeled recently or so over time or even documented or debunked?

I don't know much of what happens in below or "above" Antarctica.
The Earth's gravity well isn't underneath Antarctica, if that is what you're thinking!

Note that the following is not a valid physical model:

Staff Emeritus
Note that the following is not a valid physical mode

Of course not.

It's turtles all the way down.

Richard Crane, MidgetDwarf, russ_watters and 3 others
Gold Member
As a side question it's interesting that aurora's don't happen as often over Antarctica,

Not correct. They happen there every time they happen in the northern hemisphere

whilst probably heavier matter collects in the gravity well instead.

Seriously, you didnt read what was written in answers to you earlier aye ?

Your understanding of a gravity well is not correct
There is NO up or down in space, therefore NOTHING collects at the "bottom" of the Earth
Everything that falls into Earth's gravity will usually end up on earth

My further hypothesis is that due to this the nature of aurora borealis and aurora Australis might be different.

Again, as I have already stated ... there is no difference in occurrence between them

I don't know much of what happens in below or "above" Antarctica.

Below Antarctica is inside the Earth. Above Antarctica is in the atmosphere or out into space
It might be a small matter of documented spectrographic analysis of the australis auroras in comparison to the borealis to determine any truth to the assertion that there's any different matter orbiting around Antarctica vs. Artic Circle.

Again, there is no difference other than variations in the way the aurora curtain sways. We know this because of satellites that image both regions and see aurorae at the same time at both poles

Dragrath and PeroK
TimeSkip
The Earth's gravity well isn't underneath Antarctica, if that is what you're thinking!
Not what I exactly meant, but isn't it deepest around Antarctica?

Dragrath, davenn, Vanadium 50 and 1 other person
Not what I exactly meant, but isn't it deepest around Antarctica?
It's deepest at the centre of the Earth, not anywhere on its surface.

Dragrath
2022 Award
Not what I exactly meant, but isn't it deepest around Antarctica?
The Earth is not sitting on a dent in a rubber sheet, if you've been misled by diagrams of that sort.

russ_watters and PeroK
Staff Emeritus
Gold Member
Not what I exactly meant, but isn't it deepest around Antarctica?
No.
I know that they usually depict a spherical Earth and Sun sitting in their respective dips representing the Gravity wells , but that is just artistic license and not representative of what the model is showing.
The warped grid lines are a 2-dimensional model of the 3-d universe. It is simplified to make a it easier to visualize. A more accurate way to represent the Earth and Sun in keeping with the model would be as circles on the grid, the circles representing the surface of each. That part of the grid inside each circle would be points under the surface of each body, with the "lowest" part of each well being at the center of the body.

Ibix
Gold Member
Not what I exactly meant, but isn't it deepest around Antarctica?

Visualizing gravitational curvature...

(2D) wrong:

(3D) better:

The deepest part of the well is at the centre of the Earth, and the curvature extends spherically and 3-dimensionally symmetrical in all directions from the centre.

But no mere diagram can really capture what's happening, even the above one. You really need to read up a little on it. It's not that hard to get your head around.

Dragrath
Staff Emeritus
2022 Award
Not what I exactly meant, but isn't it deepest around Antarctica?

Here's what I want you to do, TimeSkip. I want you to go onto the Steam platform (or download it if you don't have it yet) and purchase Kerbal Space Program. I want you to spend about 100 hours in this game building and flying spacecraft around the solar system. Not only is this a lot of fun (at least for me), but it will greatly increase your understanding of orbital mechanics and gravity. There are many resources on youtube to help you get off the ground and into orbit if you're having trouble.

If you don't want to do that, then just know that gravity isn't a 2d sheet that everything sits on. It's much more like the 2nd diagram in Dave's post just above. Note that the lines don't represent anything physical. They just represent the concept of curved spacetime in the vicinity of a massive object.

Staff Emeritus