Removing a major planet

[bloodhound31]

I am after an educated answer here.

I watched fantastic four II the other day. Good fun movie. I noticed that Saturn was consumed on the big bad dudes passage to come and destroy earth. I figured, if Saturn were removed, we would be stuffed anyway.

If one were to remove a large planet from orbit, say...Jupiter or Saturn, how would the solar system be effected? I am sure the orbits of the other planets would shift one way or another and perhaps even the sun would be effected.

I am quite certain that a question like this would have been asked before.

Is there some simple...and I mean simple... math that can illustrate and explain this?

Is there an animation or diagram that would help?

Baz.

[Jay-qu]

Ok well lets completely ignore the logistics of making mass dissapear for a moment and do a quick consideration of the centre of mass of the planet/planet or planet/sun system.

COM = (M1*r1+M2*r2)/(M1+M2)

Lets do this for the Jupiter/Sun system as it will probably have the largest effect (upon removing).

COM = (1Ms*0+0.000955Ms*(7.78*10^11))/1.000955Ms

Here I have put the mass of jupiter in terms of the sun and placed the sun at the origin. This gives the jupiter sun system a centre of mass of ~740 thousand km from the centre of the sun. This may sound like a lot, but the sun has a radius of 1.4 million km, so the centre of mass is well inside the sun.

I would suggest then that removing jupiter would not have much effect of the sun - but it would certainly have a large effect on the asteroid belt, probably sending a lot of rocks into eccentric orbits..

[bloodhound31]

Jay-qu, that is EXCELLENT! Thank you. Nice and simple.

As the rest of the inferior planets ar small in mass, would not this balancing act between the larger masses, (although the effect seems small on them),throw the inferior planets out of whack, even if by a little?


Baz.

[ngcles]

Hi Jay

Originally Posted by Jay-qu

This gives the jupiter sun system a centre of mass of ~740 thousand km from the centre of the sun. This may sound like a lot, but the sun has a radius of 1.4 million km, so the centre of mass is well inside the sun.

1.4 million km is the Sun's diameter, not radius -- but I don't think it makes much difference to your calculation (which looks okay to me).


Best,

Les D

[Jay-qu]

Apologies for my error - so the centre of mass is around the surface of the sun.

There will always be perturbations introduced to the system when you change it, but for the most part these will be very small effects. I believe the solar system would still be stable if jupiter was removed. But a few asteroids would probably be thrown around a bit.

[Barrykgerdes]

It depends on how you remove it. If it was just suddenly not there the short term effects would not be noticed except by us astronomers who wouldn't be able to find it. The long term effects would eventually change the orbits of solar system bodies particularly the asteroids that are closer to it.

However if some alien force applied a "disintergrater ray" to Jupiter we would probably have the effect of a super nova at about less than a light year. We would possibly see a flash an hour or so later and then oblivion. just like the Vorgon fleet did to make way for the space bypass or whatever they called it.

Barry

PS OK I just had to make some sort of a post to make the 300 mark.

[Coen]

The sudden removal of Jupiter would not be pleasant for the Trojan asteroids located at the Lagrangian points on Jupiter's orbit. The various asteroids that are in resonance orbits with Jupiter would also be ultimately affected - i.e. no longer in resonance lock. There will also be a considerable effect on the interlopers from the nether regions such as comets.

The interesting thing over time will be upon the nature of what outer solar system debris will make their way into the inner solar system i.e. the giant "hoover" being removed I suspect means greater chance of the Earth being hit by something.

If you Google "centre of mass of the solar system" you'll find some more information regarding what effect each of the planets has upon the solar system's COM point.

[Omaroo (Chris Malikoff)]

Originally Posted by Barrykgerdes

...just like the Vorgon fleet did to make way for the space bypass or whatever they called it.

Philistine!!!

The Vogon Constructor Fleet, under the comand of Prostetnic Vogon Jeltz, destroyed the Earth in order to make way for a hyperspace bypass.

[Coen]

Just so long as we do not discuss armpits, green putty and poetry...

[Barrykgerdes]

Originally Posted by Omaroo

Philistine!!!

The Vogon Constructor Fleet, under the comand of Prostetnic Vogon Jeltz, destroyed the Earth in order to make way for a hyperspace bypass.

Sorry about the fine details. It is about a month since my last viewing of the tape.

Baz

[Jay-qu]

Tape? run out and buy the whole trilogy (in five parts) in book form. They are a lot of fun to read