<p>We have observed impacts with Jupiter</p>

<ul>
<li><p>In 1993 comet <a href="http://en.m.wikipedia.org/wiki/Comet_Shoemaker%E2%80%93Levy_9" rel="nofollow">Shoemaker Levy 9</a> impacted. </p></li>
<li><p>In 2009 an unknown object <a href="http://en.m.wikipedia.org/wiki/2009_Jupiter_impact_event" rel="nofollow">impacted</a>. </p></li>
</ul>

<p>In each case the object was destroyed in Jupiter's atmosphere. </p>

CC BY-SA 3.0
2015-04-06T13:57:02.887Z
2015-04-06T13:57:02.887Z
andy256
<p>What happens when asteroids (or other small bodies) "collide" with a gas planet? In my head it would either go through it or just stay "inside" it due to the strong gravity. I tend to believe in the latter one, but if this is the case, does this mean that the gas giants are full of small bodies inside them?</p>

<p>Thank you.</p>

CC BY-SA 3.0
2015-04-06T14:10:10.207Z
It would be crushed into pieces by tidal forces before it hits the surface of the atmosphere. And inside the atmosphere it would be destroyed by friction and the fragments would lose speed and spiral in towards the center of gas planet. Somewhere down there the materials of the asteroid gets into equilibrium with the surrounding gases. But [huge red giant stars](https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object) like Betelgeuse on the other hand, might have even companion (neutron)stars orbiting "inside" them. Jupiter no. I'll leave the answer to a real physicist.
LocalFluff
CC BY-SA 3.0
2015-04-06T15:30:36.667Z
@LocalFluff would you care to quantify? I think the Roche limit for rocky material would be *inside* Jupiter. Certainly, something of low density, like a comet, might break up before it gets to the surface, but not something with say 5000 kg/m$^3$.
ProfRob
CC BY-SA 3.0
2015-04-06T16:53:37.043Z
@RobJeffries It would be a huge project for me to calculate that, and since  others do it much better I lack motivation to do so. Maybe and likely a solid asteroid, like 16 Psyche, could enter the atmosphere before it breaks up. But I see no other destiny for it than to quickly liquify and join the general differentiation of its new environment. I think it's pretty obvious that the drag from the dense gas would prevent any solid object from orbiting inside a gaseous planet. Obvious enough to not having to go into the numbers (cause I'm lazy).
LocalFluff
CC BY-SA 3.0
2015-04-06T19:13:52.420Z
@LocalFluff: I think a reasonably dense object like a rocky or iron asteroid would have more than enough internal strength to hold itself together for  a while even inside the Roche limit. Very large objects like planets behave like fluids (for example, Earth is round because it's close to hydrostatic equilibrium), but smaller objects behave like solids. A body small enough to be non-spherical isn't big enough for tides to be a huge influence.
Keith Thompson
CC BY-SA 3.0
2015-04-06T21:22:32.010Z
@KeithThompson *"A body small enough to be non-spherical isn't big enough for tides to be a huge influence."* But then what about comet Shoemaker–Levy 9? The expectation is that most objects orbiting out there at Jupiter are pretty icy and soft. But anyway, once inside the atmosphere any object would quickly decelerate and dive into the depths where it will be crushed by pressure.
LocalFluff
CC BY-SA 3.0
2015-04-06T21:34:33.137Z
@LocalFluff: Which is why I referred specifically to rocky or iron asteroids. SL9 was obviously less strongly held together by its own internal structure. And the question mentioned asteroids, not comets.
Keith Thompson
CC BY-SA 3.0
2015-04-07T11:04:10.343Z
This discussion is pretty helpful. Since I can't accept it as an answer maybe one of you should make into an answer. Otherwise I could do it.
TomCho
CC BY-SA 3.0
2015-04-08T18:23:49.243Z
http://spaceplace.nasa.gov/jupiter/en/
Count Iblis
CC BY-SA 3.0
2016-12-21T05:05:21.180Z
I don't want to make a new answer, but on the "stay inside", a dense object like a rocky asteroid, assuming it didn't break apart on impact or by tidal forces, it would fall through a gas giant like a rock would fall through water.   Even in very high pressure, the density of a rocky asteroid would be greater than any gas on Jupiter.   At a certain point, the temperature would melt the rocky material, and in time and even further inside the planet, the material would become like plasma under high pressure, joining the plasma in the inner planet.    There are no "asteroids" inside jupiter
userLTK
<planet><gravity><asteroids><gas-giants>
Collision of asteroid and gaseous planet - what would happen
TomCho
# Collision of asteroid and gaseous planet - what would happen

(Asked by: username_0 on 2015-04-06)

What happens when asteroids (or other small bodies) "collide" with a gas planet? In my head it would either go through it or just stay "inside" it due to the strong gravity. I tend to believe in the latter one, but if this is the case, does this mean that the gas giants are full of small bodies inside them?

Thank you.

**Tags:** planet, gravity, asteroids, gas-giants

> **Comments:**
> **username_1**: It would be crushed into pieces by tidal forces before it hits the surface of the atmosphere. And inside the atmosphere it would be destroyed by friction and the fragments would lose speed and spiral in towards the center of gas planet. Somewhere down there the materials of the asteroid gets into equilibrium with the surrounding gases. But [huge red giant stars](https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object) like Betelgeuse on the other hand, might have even companion (neutron)stars orbiting "inside" them. Jupiter no. I'll leave the answer to a real physicist.  
> **username_2**: @username_1 would you care to quantify? I think the Roche limit for rocky material would be *inside* Jupiter. Certainly, something of low density, like a comet, might break up before it gets to the surface, but not something with say 5000 kg/m$^3$.  
> **username_1**: @RobJeffries It would be a huge project for me to calculate that, and since  others do it much better I lack motivation to do so. Maybe and likely a solid asteroid, like 16 Psyche, could enter the atmosphere before it breaks up. But I see no other destiny for it than to quickly liquify and join the general differentiation of its new environment. I think it's pretty obvious that the drag from the dense gas would prevent any solid object from orbiting inside a gaseous planet. Obvious enough to not having to go into the numbers (cause I'm lazy).  
> **username_3**: @username_1: I think a reasonably dense object like a rocky or iron asteroid would have more than enough internal strength to hold itself together for  a while even inside the Roche limit. Very large objects like planets behave like fluids (for example, Earth is round because it's close to hydrostatic equilibrium), but smaller objects behave like solids. A body small enough to be non-spherical isn't big enough for tides to be a huge influence.  
> **username_1**: @KeithThompson *"A body small enough to be non-spherical isn't big enough for tides to be a huge influence."* But then what about comet Shoemaker–Levy 9? The expectation is that most objects orbiting out there at Jupiter are pretty icy and soft. But anyway, once inside the atmosphere any object would quickly decelerate and dive into the depths where it will be crushed by pressure.  
> **username_3**: @username_1: Which is why I referred specifically to rocky or iron asteroids. SL9 was obviously less strongly held together by its own internal structure. And the question mentioned asteroids, not comets.  
> **username_0**: This discussion is pretty helpful. Since I can't accept it as an answer maybe one of you should make into an answer. Otherwise I could do it.  
> **username_4**: http://spaceplace.nasa.gov/jupiter/en/  
> **username_5**: I don't want to make a new answer, but on the "stay inside", a dense object like a rocky asteroid, assuming it didn't break apart on impact or by tidal forces, it would fall through a gas giant like a rock would fall through water.   Even in very high pressure, the density of a rocky asteroid would be greater than any gas on Jupiter.   At a certain point, the temperature would melt the rocky material, and in time and even further inside the planet, the material would become like plasma under high pressure, joining the plasma in the inner planet.    There are no "asteroids" inside jupiter  

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## 1 answers

### Answer by username_6 on 2015-04-06. Score: 4

We have observed impacts with Jupiter

* In 1993 comet [Shoemaker Levy 9](http://en.m.wikipedia.org/wiki/Comet_Shoemaker%E2%80%93Levy_9) impacted.
* In 2009 an unknown object [impacted](http://en.m.wikipedia.org/wiki/2009_Jupiter_impact_event).

In each case the object was destroyed in Jupiter's atmosphere.


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