colliding planets!?

[neutron_star69]

I have two questions:<br /><br />1. Could planets in our solar system ever collide?<br /><br />2. What would happen if they did, would it ruin roughly half of a planet or would they both be totally destryoed?

 

[rhodan]

<i>1. Could planets in our solar system ever collide?</i><br /><br />Highly unlikely. Only a large disruption of the Sun's gravitational field would cause the planets to abandon their rather steady orbits and perhaps adopt an orbit that's on a crash course with another planet. That could only happen if an object with huge mass would cross through or pass our Solar System.<br /><br /><i>2. What would happen if they did, would it ruin roughly half of a planet or would they both be totally destryoed?</i><br /><br />Depends on the mass and composition of the planets involved. Many scientists support the theory that our Moon was formed out of a collision of a Mars sized planet called Orpheus and (proto-) Earth, over 3 billion years ago. The left over debry after the collision formed our Moon. But were Mars to collide with Jupiter, the effects would be hardly noticeable at all.

 

[robnissen]

1. Unlikely. All the planets appear to be in very stable orbits. The only way I could see this happening, is if the sun was to pass very closely to another star. If the other star was close enough, it could perturb the orbits of even the inner solar system. That being said, even if that happened, it is unlikely that the new orbits would end up on a collision course. But it would be very easy for a planet such as Earth to be ejected from the solar system by the passing star. That would be a very bad thing.<br /><br />2. That depends on the size of the planets. If Pluto hit Jupiter, there would not be much of an effect on Jupiter (Pluto would be toast though). But if any planet hit Earth, that would be the end of all life on Earth (maybe a few microbes would survive). As far as Earth itself, current theory is that it was hit by a Mars sized planet, shortly after the solar system formed, Earth survived that blow, and the Moon was formed out of it. So, Earth would probably survive a blow by Mars, Mercury and Pluto, hard to say what the result would be with a collision with Venus, and Earth would be gone if it was hit by any larger planet.

 

[robnissen]

GMTA (great minds think alike).

 

[rhodan]

<img src="/images/icons/smile.gif" />

 

[mpai]

Several friends have already provided a logical answer. I have nothing much to add, but a short answer to both the questions is "Yes". However, it not going to take place in your life. ;-)<br /><br />So enjoy yourself neutron_star69.

 

[jatslo]

Something unseen the size of Pluto moving at 25,000 miles per hour towards a known planet sized body within our solar system? <---- Plausible ??? I say YES!!!

 

[bonzelite]

just a question: if earth's moon was birthed from a collision, then how about the scores of other moons around other planets? those were all created by collisions, too? Io, Europa, Ganymede, Callisto, Titan, Rhea, myriad others --these were all created by collisions? furthermore, these moons, then, if not a result of a collision, are then all captured objects?

 

[robnissen]

Other than Pluto/Charon, the Moon is far and away the largest satellite relative to planet size of any of the solar system's moons. That is why it would have been extremely difficult for the Earth to capture the Moon. That is also the reason why Saturn and Jupiter have so many moons, their large mass makes it easy for them to capture moons that are so much smaller. I believe, that the Moon is the only satellite known, that appears to be the result of a collision, the rest all appeared to be captured (I don't know if it is considered possible that some of the moons may have formed in place). The one possible exception is Charon, because it is close to Pluto in mass, it is possible that it formed from a collision, but that seems unlikely because the composition of Pluto seems to be very different from the composition of Charon.

 

[bonzelite]

then it is likely, at least plausible, that the myriad moons of Jupiter and Saturn, at least some of them, were planets orbiting the sun and were captured as the orbital positions of the gas giants shifted? <br /><br />

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>just a question: if earth's moon was birthed from a collision, then how about the scores of other moons around other planets? those were all created by collisions, too? Io, Europa, Ganymede, Callisto, Titan, Rhea, myriad others --these were all created by collisions? furthermore, these moons, then, if not a result of a collision, are then all captured objects?<p><hr /></p></p></blockquote><br /><br />My two cents:<br /><br />I find it highly plausible that the Moon was formed from a collision. I like the Orpheus impact theory. But I doubt that all of the moons in this solar system were formed in the same way. I suspect that their histories are as varied as they are. That's more exciting than a single story, frankly; each moon could have its own, unique story to tell!<br /><br />Of course, some are almost certainly captured objects, such as Saturn's moon Phoebe and both of Mars' natural satellites. And there is so much evidence of catastrophic collisions in the Saturn system that it seems inescapable that at least some of the moons are fragments of other bodies -- particularly the very small ones orbiting in the rings. I don't think they fragmented from Saturn; I think they fragmented from one another. But where did their parent objects come from? Again, the stories are probably as varied as the moons themselves. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[bonzelite]

yes i agree. <br /><br />it seems some of the larger moons out there are actually planets. <br /><br />

 

[CalliArcale]

Meaning that they were formed in heliocentric orbit and then captured by what are now their parent bodies? Yes. Best example is probably Neptune's large moon Triton.<br /><br />Of course, "planet" and "moon" are ultimately just matters of definition. <img src="/images/icons/wink.gif" /> Sooner or later we're going to start getting debates about what counts as a moon of Saturn and what's just a really big ring particle.... <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[CalliArcale]

That's an awful lot of gas, though. It seems very unlikely to me that volcanic eruptions could produce that much material. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>