<p>I feel like this is getting into worldbuilding a little, but a Dyson sphere is problematic.    Dyson ring or swarm is more possible.</p>
<p>One change, regarding the removal and redistribution of mass of Venus would be a change in Earth's eccentricity cycle, as Venus is one of the key planets that effects Earth's eccentricity, along with Jupiter and Saturn.    That could lead to a change in Earth's ice age cycle, which is currently on a roughly 100,000 year pattern which corresponds to one of Earth's eccentricity cycles.   Granted, any species advanced enough to disassemble a planet would be able to control climate cycles.</p>

CC BY-SA 4.0
2020-08-09T15:45:02.637Z
The issue is really the absence of planets rather than adding a concentric mass distribution: any spherically symmetric shell, swarm or statite bubble will only look like the Sun acquired a tiny extra mass to outside bodies. There is an issue with tidal work being done on the sphere by planets, causing dissipation, but it depends a lot on the choice of setup.
Anders Sandberg
CC BY-SA 4.0
2020-08-09T12:13:58.910Z
2020-08-09T12:13:58.910Z
userLTK
<p>Not really. The mass of Mercury and Venus together are just 0.0027 of Jupiter's mass. So the effect is really small.</p>
<p>Now, in principle, there are resonances where the regular tug from planets affect the long-term evolution of the orbits of other planets. The exact details get very messy, but in some cases the presence of a planet stabilizes certain orbits - or destabilises them (this is <a href="https://en.wikipedia.org/wiki/Kirkwood_gap" rel="noreferrer">very visible in the asteroid belt</a>). But <a href="https://en.wikipedia.org/wiki/Orbital_resonance#Coincidental_%27near%27_ratios_of_mean_motion" rel="noreferrer">the planetary orbits look largely non-resonant</a>. So if two planets went missing there would not be much of an effect.</p>
<p>It is likely that this is true for Jupiter too. What would happen is that the Trojan and Greek asteroids would drift out of their 1:1 resonance and end up in a loose belt, and the asteroid belt would also reorganise.</p>
<p>Overall, you don't need much mass for a Dyson sphere if you want to just collect energy. My paper on using one to settle the universe disassembled Mercury mostly as a conservative estimate to get more than enough material - I currently think you need a few largish asteroid masses, maybe Ceres (assuming it has the right elements, an important if). Conversely, Dyson element orbits will be subject to gravitational interactions from remaining planets that will cause precession and other possibly unwanted shifts one need to compensate for. But a Dyson sphere is mass-wise a microscopic thing compared to planets.</p>

CC BY-SA 4.0
2020-08-09T06:38:35.787Z
Why don't you link your paper?
planetmaker
CC BY-SA 4.0
2020-08-09T13:45:38.110Z
Mind you, any (non-magical) mechanism that removes Jupiter from the Solar System is bound to create a fair bit of havoc. ;)
PM 2Ring
CC BY-SA 4.0
2020-08-09T15:38:13.540Z
@planetmaker - My paper is not really part of an answer, so I felt it was too much self-advertising to include it in the answer. If somebody is interested, a copy can be found at http://www.fhi.ox.ac.uk/wp-content/uploads/intergalactic-spreading.pdf
Anders Sandberg
CC BY-SA 4.0
2020-08-08T21:52:47.213Z
2020-08-08T21:52:47.213Z
Anders Sandberg
<p>I've watched a few theoretical videos about Dyson spheres where they mention that the most practical way to do that would be to disassemble a planet - preferably one already close to the sun - Mercury or Venus.</p>
<p>Question: Would the solar system become completely unstable if one (or both) of those planets got disassembled? As a follow up question: what if one or more of the gas giants somehow were taken out of the solar system?</p>

CC BY-SA 4.0
2020-08-08T05:14:26.317Z
I modified your title to match your question, have a look to make sure it's still okay. I assume the answer is "very little" for Mercury and "not much in the short term, but..." for Venus, because there is a significant interaction between Earth and Venus and over very long timescales its absence might be noticeable. It's important to note that the solar system is always evolving and the planets' orbits are always interacting so some degree.
uhoh
CC BY-SA 4.0
2020-08-08T06:13:32.747Z
@uhoh Significant? As the quote in your answer [here](https://astronomy.stackexchange.com/q/36488/16685) mentions, the gravitational interaction between Venus & Earth is rather minor, and if it does cause a locking effect on Venus's rotation, that's only possible because of partial cancellation of the solar solid body tidal force by the solar atmospheric tidal force.
PM 2Ring
CC BY-SA 4.0
2020-08-08T06:39:58.547Z
@PM2Ring I don't have the "bandwidth" to write an answer here any time soon and of course the word "significant" doesn't really mean anything without context, but I'd totally forgotten about that! Thanks for the reminder :-)
uhoh
<solar-system><gravity><planetary-systems>
Impact on the rest of the solar system if Mercury or Venus were disassembled?
rodrigo-silveira
# Impact on the rest of the solar system if Mercury or Venus were disassembled?

(Asked by: username_0 on 2020-08-07)

I've watched a few theoretical videos about Dyson spheres where they mention that the most practical way to do that would be to disassemble a planet - preferably one already close to the sun - Mercury or Venus.

Question: Would the solar system become completely unstable if one (or both) of those planets got disassembled? As a follow up question: what if one or more of the gas giants somehow were taken out of the solar system?

**Tags:** solar-system, gravity, planetary-systems
> **Comments:**
> **username_1**: I modified your title to match your question, have a look to make sure it's still okay. I assume the answer is "very little" for Mercury and "not much in the short term, but..." for Venus, because there is a significant interaction between Earth and Venus and over very long timescales its absence might be noticeable. It's important to note that the solar system is always evolving and the planets' orbits are always interacting so some degree.  
> **username_2**: @uhoh Significant? As the quote in your answer [here](https://astronomy.stackexchange.com/q/36488/16685) mentions, the gravitational interaction between Venus & Earth is rather minor, and if it does cause a locking effect on Venus's rotation, that's only possible because of partial cancellation of the solar solid body tidal force by the solar atmospheric tidal force.  
> **username_1**: @PM2Ring I don't have the "bandwidth" to write an answer here any time soon and of course the word "significant" doesn't really mean anything without context, but I'd totally forgotten about that! Thanks for the reminder :-)  

---

## 2 answers

### Answer by username_4 on 2020-08-08. Score: 6 | Accepted answer

Not really. The mass of Mercury and Venus together are just 0.0027 of Jupiter's mass. So the effect is really small.

Now, in principle, there are resonances where the regular tug from planets affect the long-term evolution of the orbits of other planets. The exact details get very messy, but in some cases the presence of a planet stabilizes certain orbits - or destabilises them (this is [very visible in the asteroid belt](https://en.wikipedia.org/wiki/Kirkwood_gap)). But [the planetary orbits look largely non-resonant](https://en.wikipedia.org/wiki/Orbital_resonance#Coincidental_%27near%27_ratios_of_mean_motion). So if two planets went missing there would not be much of an effect.

It is likely that this is true for Jupiter too. What would happen is that the Trojan and Greek asteroids would drift out of their 1:1 resonance and end up in a loose belt, and the asteroid belt would also reorganise.

Overall, you don't need much mass for a Dyson sphere if you want to just collect energy. My paper on using one to settle the universe disassembled Mercury mostly as a conservative estimate to get more than enough material - I currently think you need a few largish asteroid masses, maybe Ceres (assuming it has the right elements, an important if). Conversely, Dyson element orbits will be subject to gravitational interactions from remaining planets that will cause precession and other possibly unwanted shifts one need to compensate for. But a Dyson sphere is mass-wise a microscopic thing compared to planets.

> **Comments:**
> **username_5**: Why don't you link your paper?  
> **username_2**: Mind you, any (non-magical) mechanism that removes Jupiter from the Solar System is bound to create a fair bit of havoc. ;)  
> **username_4**: @planetmaker - My paper is not really part of an answer, so I felt it was too much self-advertising to include it in the answer. If somebody is interested, a copy can be found at http://www.fhi.ox.ac.uk/wp-content/uploads/intergalactic-spreading.pdf  

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### Answer by username_3 on 2020-08-09. Score: 0

I feel like this is getting into worldbuilding a little, but a Dyson sphere is problematic. Dyson ring or swarm is more possible.

One change, regarding the removal and redistribution of mass of Venus would be a change in Earth's eccentricity cycle, as Venus is one of the key planets that effects Earth's eccentricity, along with Jupiter and Saturn. That could lead to a change in Earth's ice age cycle, which is currently on a roughly 100,000 year pattern which corresponds to one of Earth's eccentricity cycles. Granted, any species advanced enough to disassemble a planet would be able to control climate cycles.

> **Comments:**
> **username_4**: The issue is really the absence of planets rather than adding a concentric mass distribution: any spherically symmetric shell, swarm or statite bubble will only look like the Sun acquired a tiny extra mass to outside bodies. There is an issue with tidal work being done on the sphere by planets, causing dissipation, but it depends a lot on the choice of setup.  

---

