<p>If you look at the <a href="https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size#Larger_than_400_km" rel="nofollow noreferrer">mass-sorted list of (known) solar bodies</a>, and then at the list of further minor bodies, you get an idea of the impact a small body can make on todays planets in terms of their orbits: not much. Sure, one can hardly know whether there's Mars-sized bodies far out in the Kuiper belt or even Oort cloud. </p>

<p>This was different in the early solar system where big(ger) bodies and planetesimals were in much greater abundance also inward of 100AU, and some possibly in more excentric orbits.</p>

<p>However, looking at the gravitational attraction acting on a planet, the FAR dominating force it the one of the sun - the force of all other planets is negligible in comparison unless you want to send a space probe into orbit of another planet. So the re-surfacing or even destruction of one of the existing planets would have no immediately apparent effect on the orbits of the other planets - and that includes even Jupiter although that might influence the long-term evolution of orbits, especially in the asteroid region.</p>

<p>The scarred surface of the existing planets is no indication that their orbits was changed or altered significantly by the impactors - surface is much easier altered than orbits. It needs only km-sized bodies to <a href="https://en.wikipedia.org/wiki/Torino_scale" rel="nofollow noreferrer">lay waste to the complete surface of continent(s)</a> on Earth - but Earth itself will not even notice. Typically a crater is about 30x the diameter of the impacting object. And that does not count the influence of the ejecta hitting the planet's surface outside the actual crater.</p>

CC BY-SA 4.0
2020-05-04T14:36:08.717Z
2020-05-04T14:36:08.717Z
planetmaker
<p>as a short answer, you can not answer without much more detail. it will depend on the strike angle and closing velocity of the 2 objects. It will also depend on where in the planets orbit the collision took place and also the relative position of the other planets. The other planet's positions are needed to determine how the 2 bodies move after a collision. The moving objects, after the collision, could disrupt the orbits of the other objects in the solar system. Hence this is not an easy problem to solve.  A small change in the gravitation field could affect the orbits of other planets many years after the collision.</p>

<p>What you could maybe do is to get a solar system simulation and perturb the orbit of the struck planet to account for the change in momentum due to the collision. Propagate this new orbit for years and see what happens to it. It could strike another planet in 50,000 years or maybe settle in to a new stable orbit. You should also be concerned with the striking body. it could strike another object.</p>

<p>The change in momentum will depend on many factors as mentioned above, So the answer needs the exact geometry and time of the collision.</p>

<p>If the collision splits the planet you'd have to track all three of the remaining bodies. There is probably no closed-form solution for this problem.</p>

CC BY-SA 4.0
2020-05-03T20:15:31.997Z
2020-05-03T20:24:00.373Z
2020-05-03T20:24:00.373Z
Natsfan
<p>Propably 0 because the  gravitational field of the Sun is so big rest GF's dont impact the motion at all . If the velocity of the collided planet is to the Sun then that planet is doomed to be burnt.</p>

CC BY-SA 4.0
2020-05-03T22:05:49.853Z
2020-05-03T22:05:49.853Z
Jelly Strawberry
<p>There's plenty of speculation about what would happen if a large asteroid collided with the Earth itself, but less about the effect on Earth of a large asteroid or even a moon or minor planet colliding with one of our neighboring planets, e.g. Venus or Mars or Jupiter or any of them really.</p>

<p>Obviously the other planets are regularly bombarded with meteors just like the Earth, but I'm curious about what we might experience on Earth if one of the other planets suffered an especially large or catastrophic impact, perhaps one with sufficient energy to permanently alter the planet's orbit. Would life on Earth change noticeably, or nah?</p>

<p>I can imagine such an impact with one of our nearer neighbors, like Mars, might have more dramatic consequences for Earth than an impact with a more distant planet, like Neptune, but I'm not sure why. Any speculations?</p>

CC BY-SA 4.0
2020-05-03T21:04:06.080Z
Welcome to Stack Exchange! While this is an interesting question, "Any speculations?" is the wrong kind of question for this site. In SE one should try to ask questions that can have clear answers.
uhoh
<planet><solar-system><earth><impact><orbital-migration>
What would happen to the Earth if the orbit of another planet in the Solar System was disrupted by a cataclysmic collision with a large body?
Fouquieria
# What would happen to the Earth if the orbit of another planet in the Solar System was disrupted by a cataclysmic collision with a large body?

(Asked by: username_0 on 2020-05-03)

There's plenty of speculation about what would happen if a large asteroid collided with the Earth itself, but less about the effect on Earth of a large asteroid or even a moon or minor planet colliding with one of our neighboring planets, e.g. Venus or Mars or Jupiter or any of them really.

Obviously the other planets are regularly bombarded with meteors just like the Earth, but I'm curious about what we might experience on Earth if one of the other planets suffered an especially large or catastrophic impact, perhaps one with sufficient energy to permanently alter the planet's orbit. Would life on Earth change noticeably, or nah?

I can imagine such an impact with one of our nearer neighbors, like Mars, might have more dramatic consequences for Earth than an impact with a more distant planet, like Neptune, but I'm not sure why. Any speculations?

**Tags:** planet, solar-system, earth, impact, orbital-migration

> **Comments:**
> **username_1**: Welcome to Stack Exchange! While this is an interesting question, "Any speculations?" is the wrong kind of question for this site. In SE one should try to ask questions that can have clear answers.  

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## 3 answers

### Answer by username_2 on 2020-05-04. Score: 2

If you look at the [mass-sorted list of (known) solar bodies](https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size#Larger_than_400_km), and then at the list of further minor bodies, you get an idea of the impact a small body can make on todays planets in terms of their orbits: not much. Sure, one can hardly know whether there's Mars-sized bodies far out in the Kuiper belt or even Oort cloud.

This was different in the early solar system where big(ger) bodies and planetesimals were in much greater abundance also inward of 100AU, and some possibly in more excentric orbits.

However, looking at the gravitational attraction acting on a planet, the FAR dominating force it the one of the sun - the force of all other planets is negligible in comparison unless you want to send a space probe into orbit of another planet. So the re-surfacing or even destruction of one of the existing planets would have no immediately apparent effect on the orbits of the other planets - and that includes even Jupiter although that might influence the long-term evolution of orbits, especially in the asteroid region.

The scarred surface of the existing planets is no indication that their orbits was changed or altered significantly by the impactors - surface is much easier altered than orbits. It needs only km-sized bodies to [lay waste to the complete surface of continent(s)](https://en.wikipedia.org/wiki/Torino_scale) on Earth - but Earth itself will not even notice. Typically a crater is about 30x the diameter of the impacting object. And that does not count the influence of the ejecta hitting the planet's surface outside the actual crater.


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### Answer by username_3 on 2020-05-03. Score: 1

as a short answer, you can not answer without much more detail. it will depend on the strike angle and closing velocity of the 2 objects. It will also depend on where in the planets orbit the collision took place and also the relative position of the other planets. The other planet's positions are needed to determine how the 2 bodies move after a collision. The moving objects, after the collision, could disrupt the orbits of the other objects in the solar system. Hence this is not an easy problem to solve. A small change in the gravitation field could affect the orbits of other planets many years after the collision.

What you could maybe do is to get a solar system simulation and perturb the orbit of the struck planet to account for the change in momentum due to the collision. Propagate this new orbit for years and see what happens to it. It could strike another planet in 50,000 years or maybe settle in to a new stable orbit. You should also be concerned with the striking body. it could strike another object.

The change in momentum will depend on many factors as mentioned above, So the answer needs the exact geometry and time of the collision.

If the collision splits the planet you'd have to track all three of the remaining bodies. There is probably no closed-form solution for this problem.


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### Answer by username_4 on 2020-05-03. Score: 0

Propably 0 because the gravitational field of the Sun is so big rest GF's dont impact the motion at all . If the velocity of the collided planet is to the Sun then that planet is doomed to be burnt.


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