Planet Removed From a Solar System


Banded Mongoose
I haven't finished reading the World Builder Handbook, so not sure if this is covered in that book or any book really in any edition.

What happens to a solar system if a planet is "removed" from it? Say it blows up or is moved elsewhere.

The orbits are all influenced by gravity and when that influence is removed from neighbors how does that effect the rest of the system?
Not covered.
WBH creates a snapshot of the current state of a system for the most part, and does not attempt to do any n-body gravity stuff, except to roughly compute a world's 'Hill Sphere' or its dominate region of gravitational influence, and that is mainly to account for how far moons can orbit around the world. If the planet goes away, then those moons would either go with it, or wander off into new orbits as planets, or escape the system... or crash into the sun(s) or other worlds.

So I ran it thru ChatGPT and here is what it came up with.

If we remove the Earth and Moon from the solar system, the gravitational dynamics within the system would be significantly altered. Here's a simulation of how the gravity might behave, assuming only the other planets and the Sun remain:
  1. Sun (center of the solar system): The Sun's gravitational influence remains the dominant force in the solar system. All other planets orbit around it.
  2. Mercury: Mercury continues its orbit around the Sun as usual, but without the gravitational pull of Earth and Moon, its trajectory might be slightly altered.
  3. Venus: Venus remains locked in its orbit around the Sun, without any significant change caused by the absence of Earth and Moon.
  4. Mars: Mars also continues its orbit around the Sun, unaffected by the removal of Earth and Moon.
  5. Jupiter and Saturn: These gas giants are not directly influenced by the absence of Earth and Moon.
  6. Uranus and Neptune: These ice giants remain mostly unaffected by the removal of Earth and Moon.
Overall, the simulated gravity in the solar system would mostly follow the same patterns, with the Sun being the dominant gravitational force and the planets continuing their elliptical orbits around it. However, the gravitational interactions between planets might undergo some minimal changes due to the absence of Earth and Moon's gravitational fields.

Basically a big nothing burger, but the opening paragraph and closing paragraph contradict each other.

As neat it would be to see a solar system come a part, it basically stays relatively unchanged?
What the system does really depends on the size of the planet being "removed".

Then if you remove Jupiter, chaos ensues, maybe?

If Jupiter was suddenly removed from our solar system, it would have significant effects on the gravitational dynamics within the system. Here are some of the key impacts:
  1. Orbit Disruptions: Jupiter, being the largest planet, has a massive gravitational influence on the other planets in our solar system. Its removal would cause disruption in the orbits of nearby planets like Mars, Earth, Venus, and Mercury. These planets would experience changes in their elliptical orbits, altering their distance from the Sun and the periods of their revolutions.
  2. Asteroid Belt Dynamics: Jupiter's gravity plays a crucial role in shaping and stabilizing the asteroid belt located between Mars and Jupiter. Without Jupiter's gravitational influence, the asteroid belt would become more chaotic and less stable. The gravitational interactions between asteroids would become stronger, leading to increased collisions and potential ejection of some asteroids from the belt.
  3. Cometary Impact Frequency: Jupiter acts as a gravitational shield by attracting and absorbing a significant number of comets that could potentially impact inner planets. With Jupiter's removal, the frequency of cometary impacts on the inner planets, including Earth, could increase. This would pose a higher risk of catastrophic events on these planets.
  4. Outer Planets' Orbits: Jupiter not only affects inner planets but also plays a significant role in the dynamics of the outer planets like Saturn, Uranus, and Neptune. Their orbits would undergo changes, becoming more inclined and eccentric, as the stabilizing influence of Jupiter diminishes. This could lead to increased interactions between these outer planets and potential disturbances in their respective moon systems.
  5. Gravitational Perturbations: Jupiter's gravity affects the entire solar system, exerting a subtle influence on all other celestial bodies. The gravitational perturbations caused by its absence would ripple throughout the system, affecting the orbits of asteroids, dwarf planets, and even distant objects like comets in the Oort Cloud.
It is essential to note that these effects are complex and would require detailed simulations to precisely predict the exact outcomes of removing Jupiter. Additionally, the removal of such a massive planet from the system is purely hypothetical and not realistically achievable in practice.
As I recall, the irony is that Jupiter should have been named Saturn, eater of debris, that may have prevented a lot of that from hitting Earth.

God of real estate.


If you somehow plucked Jupiter out of the solar system without directly influencing any other object... well, the Trojans would disperse and the Kirkwood gaps would fill up. No idea on what timescales but much longer than a human lifespan. It wouldn't be disaster movie stuff.
If you want to find out what happens when you monkey around with a solar system? It sounds like you need Universe Sandbox: You can run simulations of this sort of thing. See what happens when you replace the Sun with a black hole. Smash Titan into the Earth.