Something big smashed into Jupiter

The other year an asteroid the sized of a building hit Russia and was stopped entirely by our atmosphere.


I’m not debating the power of an atmosphere to destroy something; just saying it’s not a smash.

1 Like

Not sure if “smash” is defined in any way which is meaningful in the context of interplanetary collisions. If I jump into a pool I make a splash. If I fall at terminal velocity into water then thats a smash. At that speed, water behaves like concrete.

If you fall into Jupiter, you will be moving at 50km/s at the very least, because that is Jupiter escape velocity. At that speed, the atmosphere of Jupiter behaves like concrete.

Also, the density of Jupiter increases with depth. Even if the outer layers of the atmosphere don’t stop you, then lower layers, which are denser than concrete certainly will.


At that speed, the atmosphere of Jupiter behaves like concrete

Does it?

“concrete” is another bad analogy, because we don’t have any good words for the environment under discussion. I could make up totally new words to describe what is going on, but that would not be very helpful.


I saw this on cnet earlier, but couldn’t help reading the headline as a Chuck Tingle title

Jupiter Slammed In The Butt By Something So Big We Saw It On Earth


Other times Jupiter has been hit by an object there have been light flashes (for example this happened with the fragments of Comet Shoemaker-Levy hit Jupiter in 1994):

And that comet was obviously visible from Earth, btw, as astronomers watched Jupiter’s gravity break it apart before drawing it in. The Wikipedia page describes the impacts:


On Earth you pass gas, on Soviet Jupiter gas passes you!


Technically still a splash, but it’s your body doing the splashing! :laughing:


As others have noted, at high enough relative velocities, fluids behave like solids. Conversely, over long enough time spans, large solids become fluid under their own weight.

But in more detail, a solid object striking a gas with enough momentum will rapidly ionize that gas into a hot plasma as it’s compressed. The heat of the plasma in turn dissociates the molecular bonds holding the impacting object together.

Or for a safer demonstration, fill a tub with water and try slapping the surface really fast.

That’s it in a nutshell. Simple classical mechanics.

Surface tension is part of it, but even without surface tension, the molecules have inertia. The more rapidly you want to accelerate them, the more kinetic energy you have to transfer. In this case what the impact object smashed into is every freaking gas molecule in it’s way. Or, since motion is relative, every single gas molecule in it’s way smashed into the object, tearing it apart.


Jupiter is made of mostly gas, not liquid.

Gas is mostly space, not molecules. Especially at the outermost edge of an atmosphere.

Sure. But that’s not a smash.

Gases and liquids are both fluids.

That statement makes no sense. Most of Jupiter’s atmosphere is molecular hydrogen, with lots of molecular helium, an assortment of other molecular gasses, and some gaseous organic molecules. It’s a moot point though, as even individual atoms have inertia, which is what the impact object smashed into.

I gradually realized as I went through your “well, actuallies” with the people answering your question that you were interested in litigating semantics, not exploring the science of the impact. Nonetheless, the answers you recieved may benefit someone interested in the science.


Gas giants are very unlikely to not have a solid core.
Is the name confusing?

“Smashing” has many meanings. Some smashing can be seen on porn-sites.

1 Like

Reminds me of a professor I had back in my aerospace engineering days who was fond of saying, “lots of things are immersed in fluids. Like airplanes.”


Thats true. There are more airplanes in the sea than submarines in the sky.


Technically plasmas are also fluids, though the mathematics of a charged fluid are a little different.

I suspect the commenter who asked the question was trying to imply that an object can’t smash into something that isn’t all one solid piece. This misses a number of nuances, not the least of which is that not all solids are composed of macromolecules, and that smashing into a bunch of little molecules is still smashing.



(Geeking out severely) I love sciency discussions when people actually have knowledge of the subject! And if we are litigating semantics, I feel it necessary to point out that “mostly space and not molecules” is a nonsensical statement, since atoms, and there for molecules, are almost entirely empty space, with every bit of matter in the universe contained in that “almost.”


Probably not this:


It seems you’re trying to say:

“It’s basically like a cosmic belly flop.”


Isn’t physics weird? (And the smaller things become, the weirder they get.)