<p><strong>tl;dr:</strong> The Earth receives 40,000 tons of dust from space every year, but looses 95,000 tons of Hydrogen and 1,600 tons of Helium every year as well. After all additional effects are balanced, <strong>the Earth looses about 50,000 tons a year</strong>.</p>
<hr />
<p>It seems a similar question was asked in Astronomy Stack Exchange, and <a href="https://astronomy.stackexchange.com/a/11830/7982">this short answer</a> links to the BBC News article <a href="https://www.bbc.com/news/magazine-16787636" rel="noreferrer">Who, What, Why: Is the Earth getting lighter?</a> which answers this question.</p>
<blockquote>
<p>There are factors that are causing Earth to both gain and lose mass over time, according to Dr Chris Smith, a medical microbiologist and broadcaster who tries to improve the public understanding of science.</p>
<p>Using some back-of-the-envelope-style calculations, Dr Smith, with help from physicist and Cambridge University colleague Dave Ansell, drew up a balance sheet of what's coming in, and what's going out. All figures are estimated.</p>
<p><strong>By far the biggest contributor to the world's mass is the 40,000 tonnes of dust that is falling from space to Earth</strong>, says Dr Smith.</p>
</blockquote>
<p>Surprisingly, General Relativistic effects of Global Warming is considered!</p>
<blockquote>
<p>Nasa has calculated that the Earth is gaining energy due to rising temperatures. Dr Smith and his colleague Mr Ansell estimate this added energy increases the mass of Earth by a tiny amount - <strong>160 tonnes</strong>.</p>
</blockquote>
<p>Using <span class="math-container">$E=mc^2$</span> that works out to about <span class="math-container">$1.4 \times 10^{22}$</span> Joules/year or <span class="math-container">$4.6 \times 10^{14}$</span> Watts. That's about 3.6 Watts/meter^2 or about 0.3% of the total power coming from the Sun, so it does seem to be back-of-the-envelope-in-the ballpark correct!</p>
<blockquote>
<p>But there is something else that is making the planet lose mass. Gases such as hydrogen are so light, they are escaping from the atmosphere.</p>
<p>&quot;Physicists have shown that the Earth is losing about three kilograms of hydrogen gas every second. <strong>It's about 95,000 tonnes of hydrogen that the planet is losing every year</strong>.</p>
<p>&quot;The other very light gas this is happening to is helium and there is much less of that around, so <strong>it's about 1,600 tonnes a year of helium that we lose</strong>.&quot;</p>
<p>So taking into account the gains and the losses, Dr Smith reckons <strong>the Earth is getting about 50,000 tonnes lighter a year</strong>, which is just less than half the gross weight of the Costa Concordia, the Italian cruise liner, that ran aground recently.</p>
</blockquote>

CC BY-SA 4.0
2019-04-13T15:55:04.400Z
I wonder if the mass loss associated to radioactive decay is a significant contributor to this mass balance.
Also, we might be loosing Hydrogen, but there is also a shower of alpha particles coming from the Sun, and those are hydrogen nuclei. I wonder is such effects were taken into account.
Interestingly, with those numbers it might not bee too far in the future the time when human created mass gains and losses (though space exploration and extraterrestrial mining ) will be grater than natural ones.
Camilo Rada
CC BY-SA 4.0
2019-04-13T16:43:40.530Z
@CamiloRada these are good points. Energy stored in the nucleus (before decay) and energy deposited and stored as heat (after) will have the same mass. It's only the total energy of the Earth that counts, so it's just the heat in versus heat out. Radioactive decay is steady but global warming is the sudden change.
uhoh
CC BY-SA 4.0
2019-04-13T16:50:50.643Z
Not really. Because the energy produced by radioactive decay have already created a temperature gradient that carries that energy out to the surface and is then radiated to space. Effectively been lost. Otherwise the temperature of Earth's would be rising.
Camilo Rada
CC BY-SA 4.0
2019-04-13T16:57:33.763Z
@CamiloRada oh you're indeed right. Heat due to radioactivity is (eventually) radiated into space and therefore represents a continuous loss of mass.
uhoh
CC BY-SA 4.0
2020-02-21T15:03:59.863Z
@CamiloRada [Alpha particle](https://en.wikipedia.org/wiki/Alpha_particle)s are helium nuclei, not hydrogen.
Spencer
CC BY-SA 4.0
2020-02-23T15:20:06.040Z
@Spencer You are rigth. Sorry.
Camilo Rada
CC BY-SA 4.0
2019-04-13T12:34:42.647Z
2019-04-13T12:34:42.647Z
2020-06-18T08:25:19.090Z
uhoh
<p>There is meteoric material falling on the Earth constantly, as well as some protons and other light nuclei from the solar wind as well as from cosmic rays. </p>

<p>At the same time Earth's atmosphere looses gas to space, especially the lightest elements like hydrogen and helium. </p>

<ul>
<li><a href="https://earthscience.stackexchange.com/q/16577/6031">Where does molecular hydrogen in the atmosphere come from?</a> is currently unanswered.</li>
</ul>

<p>Does one process dominate the rate of change of Earth's mass? Is Earth getting heavier or lighter?</p>

CC BY-SA 4.0
2019-04-11T01:07:44.297Z
https://earthscience.stackexchange.com/questions/4477/change-in-earth-mass-since-the-time-of-the-dinosaurs (lacks sources). https://astronomy.stackexchange.com/questions/12629/does-the-mass-of-the-earth-change (ditto). https://astronomy.stackexchange.com/questions/11823/if-50-tons-or-more-of-debris-falls-to-earth-everyday-is-earth-getting-heavier/11831#11831
Keith McClary
CC BY-SA 4.0
2019-04-11T01:15:57.167Z
@KeithMcClary thank you for the help. [this answer](https://astronomy.stackexchange.com/a/11830/7982) seems the most concise and definitive but it's on another site (so we can't dupe it). It links to [this](https://www.bbc.com/news/magazine-16787636) which cites *hard numbers* both for infall and loss. The answer here in Earth Science SE though is not a good match. Would you consider writing up a short answer and adding these and I can accept it? That way it points readers to good answers both here and in other sites.
uhoh
CC BY-SA 4.0
2019-04-11T01:21:09.550Z
Also https://en.wikipedia.org/wiki/Earth_mass#Variation I don't want to write an answer.
Keith McClary
CC BY-SA 4.0
2019-04-11T01:54:43.730Z
okay, if nobody else does in the next day or two, I'll wrap it up myself. Thanks!
uhoh
CC BY-SA 4.0
2019-04-13T12:36:01.333Z
@KeithMcClary have done so, thanks! Who'd have thought that the General Relativistic effects of Global Warming would have factored!?
uhoh
<atmosphere><solar-terrestrial-physics>
Is Earth getting heavier or lighter?
uhoh
# Is Earth getting heavier or lighter?

(Asked by: username_0 on 2019-04-09)

There is meteoric material falling on the Earth constantly, as well as some protons and other light nuclei from the solar wind as well as from cosmic rays.

At the same time Earth's atmosphere looses gas to space, especially the lightest elements like hydrogen and helium.

* [Where does molecular hydrogen in the atmosphere come from?](https://earthscience.stackexchange.com/q/16577/6031) is currently unanswered.

Does one process dominate the rate of change of Earth's mass? Is Earth getting heavier or lighter?

**Tags:** atmosphere, solar-terrestrial-physics

> **Comments:**
> **username_1**: https://earthscience.stackexchange.com/questions/4477/change-in-earth-mass-since-the-time-of-the-dinosaurs (lacks sources). https://astronomy.stackexchange.com/questions/12629/does-the-mass-of-the-earth-change (ditto). https://astronomy.stackexchange.com/questions/11823/if-50-tons-or-more-of-debris-falls-to-earth-everyday-is-earth-getting-heavier/11831#11831  
> **username_0**: @username_1 thank you for the help. [this answer](https://astronomy.stackexchange.com/a/11830/7982) seems the most concise and definitive but it's on another site (so we can't dupe it). It links to [this](https://www.bbc.com/news/magazine-16787636) which cites *hard numbers* both for infall and loss. The answer here in Earth Science SE though is not a good match. Would you consider writing up a short answer and adding these and I can accept it? That way it points readers to good answers both here and in other sites.  
> **username_1**: Also https://en.wikipedia.org/wiki/Earth_mass#Variation I don't want to write an answer.  
> **username_0**: okay, if nobody else does in the next day or two, I'll wrap it up myself. Thanks!  
> **username_0**: @username_1 have done so, thanks! Who'd have thought that the General Relativistic effects of Global Warming would have factored!?  

---

## 1 answers

### Answer by username_0 on 2019-04-13. Score: 15 | Accepted answer

**tl;dr:** The Earth receives 40,000 tons of dust from space every year, but looses 95,000 tons of Hydrogen and 1,600 tons of Helium every year as well. After all additional effects are balanced, **the Earth looses about 50,000 tons a year**.

---

It seems a similar question was asked in Astronomy Stack Exchange, and [this short answer](https://astronomy.stackexchange.com/a/11830/7982) links to the BBC News article [Who, What, Why: Is the Earth getting lighter?](https://www.bbc.com/news/magazine-16787636) which answers this question.

> There are factors that are causing Earth to both gain and lose mass over time, according to Dr Chris Smith, a medical microbiologist and broadcaster who tries to improve the public understanding of science.
>
> Using some back-of-the-envelope-style calculations, Dr Smith, with help from physicist and Cambridge University colleague Dave Ansell, drew up a balance sheet of what's coming in, and what's going out. All figures are estimated.
>
> **By far the biggest contributor to the world's mass is the 40,000 tonnes of dust that is falling from space to Earth**, says Dr Smith.

Surprisingly, General Relativistic effects of Global Warming is considered!

> Nasa has calculated that the Earth is gaining energy due to rising temperatures. Dr Smith and his colleague Mr Ansell estimate this added energy increases the mass of Earth by a tiny amount - **160 tonnes**.

Using $E=mc^2$ that works out to about $1.4 \times 10^{22}$ Joules/year or $4.6 \times 10^{14}$ Watts. That's about 3.6 Watts/meter^2 or about 0.3% of the total power coming from the Sun, so it does seem to be back-of-the-envelope-in-the ballpark correct!

> But there is something else that is making the planet lose mass. Gases such as hydrogen are so light, they are escaping from the atmosphere.
>
> "Physicists have shown that the Earth is losing about three kilograms of hydrogen gas every second. **It's about 95,000 tonnes of hydrogen that the planet is losing every year**.
>
> "The other very light gas this is happening to is helium and there is much less of that around, so **it's about 1,600 tonnes a year of helium that we lose**."
>
> So taking into account the gains and the losses, Dr Smith reckons **the Earth is getting about 50,000 tonnes lighter a year**, which is just less than half the gross weight of the Costa Concordia, the Italian cruise liner, that ran aground recently.

> **Comments:**
> **username_2**: I wonder if the mass loss associated to radioactive decay is a significant contributor to this mass balance. Also, we might be loosing Hydrogen, but there is also a shower of alpha particles coming from the Sun, and those are hydrogen nuclei. I wonder is such effects were taken into account. Interestingly, with those numbers it might not bee too far in the future the time when human created mass gains and losses (though space exploration and extraterrestrial mining ) will be grater than natural ones.  
> **username_0**: @username_2 these are good points. Energy stored in the nucleus (before decay) and energy deposited and stored as heat (after) will have the same mass. It's only the total energy of the Earth that counts, so it's just the heat in versus heat out. Radioactive decay is steady but global warming is the sudden change.  
> **username_2**: Not really. Because the energy produced by radioactive decay have already created a temperature gradient that carries that energy out to the surface and is then radiated to space. Effectively been lost. Otherwise the temperature of Earth's would be rising.  
> **username_0**: @username_2 oh you're indeed right. Heat due to radioactivity is (eventually) radiated into space and therefore represents a continuous loss of mass.  
> **username_3**: @username_2 [Alpha particle](https://en.wikipedia.org/wiki/Alpha_particle)s are helium nuclei, not hydrogen.  
> **username_2**: @username_3 You are rigth. Sorry.  

---

