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Author Topic: What if a stray planet entered our solar system?  (Read 3383 times)

Offline FuzzyUK

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What if a stray planet entered our solar system?
« on: 20/08/2011 10:17:52 »
Say a stray planet entered our solar system, what are the chances of it being immediately captured into a near circular orbit around the sun given that mass, speed and angle of approach would seem very critical factors?

I don't see a circular orbit as a likelyhood since such a celestial object would likely get slung-shot either around the sun and out into deep space again, or slung-shot into a widely elliptical orbit around the sun.

Would a planet with a widely elliptical orbit eventually settle down over the aeons of time into a circular orbit, and if so what mechanism would promote this?


 

Offline syhprum

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What if a stray planet entered our solar system?
« Reply #1 on: 20/08/2011 13:11:36 »
Pluto at one time classed as a planet is probably such an object on a much more elliptical orbit than the regular planets and way out of the elliptical plane.
 

Offline lightarrow

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What if a stray planet entered our solar system?
« Reply #2 on: 20/08/2011 14:06:33 »
"What if a stray planet entered our solar system?"

Without having paid the ticket? Too bad...
 

Offline Soul Surfer

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What if a stray planet entered our solar system?
« Reply #3 on: 24/08/2011 09:30:05 »
Stray "planets" are entering the solar system all the time.  They are small and we mostly call them comets.  Most of the comets we see are periodic and part of the solar system while a few of them are actually on hyperbolic orbits and we will see them only once. there are probably many more on more extreme hyperbolic orbits that we never see.

A stray earth size planet entering the solar system and having a low enough angular momentum to reach the inner solar system would behave very much like a very big comet and slightly disturb the other planets but cause no significant problems.  The probability of a collision is extremely low.  It is possible that it would lose enough energy with its interactions with the other planets to enter a closed orbit like a long period comet.  Capture to a low ellipticity orbit would require a very close encounter with a large planet like Jupiter and would be very improbable.


A stray Jupiter sized planet would cause much more disruption but this would be easily detected very many years before it happened because of the size and brightness of the object.  It would be much harder to capture than a smaller object.

Remember in gravitational dynamics two objects that approach each other and interact only by gravity cannot ever go into orbit round each other without the intervention of other forces.  These must be either self generated, like rocket motors,  The result of a collision with another body or the result of a strong gravitational interaction with a third body where energy is transferred and the other body is accelerated.

If objects are in circular orbits around each other it is almost certain that these objects formed together out of the same gas cloud.

« Last Edit: 24/08/2011 09:39:25 by Soul Surfer »
 

Offline Matthew L

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What if a stray planet entered our solar system?
« Reply #4 on: 24/08/2011 09:34:04 »
At a safe distance we'd destroy the planet with all our nuclear capabilities.

See this Link: newbielink:http://en.wikipedia.org/wiki/Endorian_Holocaust [nonactive]
Read the bottom of the page :")
« Last Edit: 24/08/2011 09:35:43 by Matthew L »
 

Offline Joe L. Ogan

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What if a stray planet entered our solar system?
« Reply #5 on: 24/08/2011 15:20:03 »
You must realize that a planet would not be so easy to destroy.  If you broke it up, you would have the smaller pieces to contend with.  Thanks for comments.  Joe L. Ogan
 

Offline Matthew L

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What if a stray planet entered our solar system?
« Reply #6 on: 27/08/2011 21:35:15 »
People ought to remember that galaxies are mostly just empty space. That is why when we colloid with Andromeda there will be no star collisions. 
 

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What if a stray planet entered our solar system?
« Reply #6 on: 27/08/2011 21:35:15 »

 

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