What would happen if a star or large planet entered our solar system?

Question

I calculated that a star the size of our sun coming our way would be seen many 1000's of years before it got to us. But how about a dark body like jupiter on course for us. It would not have to hit the earth to upset the orbits of the planets

Answer 1

the nearest star passing the solar system is barnard's star passing the solar system in a distance larger than 3 lightyears no earlier than 10.000 years in the future .. soo no star in sight...

a dark object the size of jupiter ..hmm...
the direct gravitational influence of ALL yet known planets within the solar system can't match up with the suns gravitational force.
The whole system must have been stable since more than a billion years now (4 billion ?). A few years ago all planets where in a row and some people claimed we are about to have severe floodings cause of that. nothing happens.

if such a planet would appear it has loooooots of space to run through the system without hitting anything and it must come with the correct speed and the correct vector to get caught in an orbit. the chances are very very small that this is the case.

if such a planet would cross near the earth i bet it would cross so fast that you are not even able to take out your camera to make a photo of it. And depending on simple newtonian mechanics the earth mass is high enough to have such a momentum that no major trajectory change should occur.

what possibly happens is, that a jupiter sized mass running through the system would change trajectories of a few asteroids which may cross the planets path.
those asteroids may cause a concern, but as already mentioned above SPACE is huuughe the solar system has alot of it and the chances that such an asteroid hits our tiny blue pearl are really really small.
If you take a look at Nasa's NEO website you may freak out for having so many asteroids nearby but from statistics .. we get hit approx. every 300.000 years soo .. ... space is called space cause its basically empty space

and if that is not enough
the oldest objects in space are 'globular clusters' like M13 for example. Those clusters are made of up to more than 100.000 stars which orbit each other in a relative small section of space without colliding since billions of years. If these objects exists since such a long time without destroying themselves in collisions, why then should a small body like jupiter should mess up our solar system which appears to be stable since at least 1 or 2 billion years ?

chances are better to win the lottery, don't you think ? ;-)

Answer 2

A body the size of Jupiter or a small star, as it passed through the solar system, could have the following effects on the planets here (I suspect there are more possibilities, but these are the most obvious, I think):

1. Not much. The solar system is vast. The planets are spread out in a disk. It is likely that the Jupiter would go right through and we would barely notice the gravitational effects, except maybe a slight orbital change in eccentricity or inclination of the planet that it passed closest to.

2. Since Earth is of primary concern... If it passed just a few million miles from the earth, it could upset the Earth's orbit, causing a shift in eccentricity or inclination that might cause our climate to change a bit. I doubt that this would be permanent; the planets seem to be in nearly elliptical orbits and in some sort of spacing harmonic that would eventually move earth back to where it originally was. Of course we might all be dead by then, but hey, I'm just speculating.

3. If it passed really close to earth, it is possible that it could eject earth from the solar system altogether. That would be bad. A really close pass might even tear the earth apart, if the body passed within the roche limit of itself and the earth.

4. If it hit the earth, well, that would be really bad.

5. If it passed really close to another planet it could destroy or eject that planet. This could be bad for us if the angle was such that mars was suddenly careening around the solar system in a wild orbit that crossed jupiter or the earth, as there would then be the possibility of Earth disruption or impact.

6. If it passed near to the asteroid belt or Kuiper belt it might cause a large increase in the number of Earth crossing asteroids and comets.

Like I said, there are probably a lot more possibilities, but those are a few that I could think of right away. The moslt likely answer though is nothing. Space is very BIG.

Answer 3

It is possible for another star to enter our solar system, or at least pass nearby. The chances of such an event are somewhere between slim and none. The star system that's nearest to us right now is about 4.5 light years away, meaning that if for some reason it began moving towards us near the speed of light, which is impossible, it would still take it about 4 years to get here. Elenin is just a plain ol' comet. There are billions of comets in and around our solar system. Some of them move inward toward the sun and pass relatively close to Earth. Some comets have struck Earth in the past, and will do so in the future, but Elenin definitely will not. Elenin will pass fairly close to Earth, but there's no way it can trigger earthquakes or any other events on our planet because it simply doesn't have enough mass to do so, no matter how it may momentarily align with other solar system bodies.

Answer 4

You can figure these things out for yourself, you know. Just write a computer program to solve the many-body problem by integration over small time increments. Set up an initial condition for the solar system, using an ephemeris to get the planets positions and velocities correct.

When it comes to the sun, you should place it such that its mass is on the opposite side of the origin from the barycenter of all the planets combined, just far enough to set the total barycenter of the solar system at the origin of the coordinate system. The sun's initial velocity should be set such that the sun's momentum exactly cancels the momentum of all the planets.

Once you've done that, let your model solar system evolve over time and check it's position at some later moment with the corresponding entry in the ephemeris. If they match, then your program is working.

Next, toss in another data entry for your interloping planet. You can decide for yourself what the interloper's mass and initial trajectory should be. Run time forward as before, and you'll see whether or how badly the interloper stirred things up in the solar system.

For the worst case scenario, read "When Worlds Collide" by Philip Wylie.

Answer 5

If a planet sized body entered our solar system it could be catastrophic if it collided with us or a nearby planet. If a star would enter our solar system, due to it's size and mass, it would head for our sun and either collide or go into orbit with our sun becomming a binary star. Either way, it would probably be bad news for us as even if the sun did not fry us on it's way in, the effects of our planet's ecosystem from a second sun could be fatal.

Answer 6

Well theres a lot of space between the planets so I guess it would fall into orbit around the sun and as long as it didnt wobble about too much theres a chance we wouldnt be affected, it it collided snooker ball style we would get meteor showers at the very best. Worst case would be some sort of extinction event.

Please note I am totally unqualified to answer this question.

Answer 7

True...it would indeed affect all of the planetary orbits as well as the position of the sun...it could "throw" the planets out of their orbits and even capture some into a new orbit around this new mass. I would think that earth would have an instantanious and dramatic climate change dependent on where it it gets "thrown" to.

Answer 8

We would be gobbled up if a sun entered our solar system.
All the astrologists would be out of work if a planet entered the solar system.........lol

Answer 9

superman would just fly to it and knock it out into space again,after all he did reverse the rotation of the earth and then returned it to normal.knocking stars and planets around would be childsplay. lol.

Answer 10

It would change the course of history of menkind,and maybe womenkind, not necesary in sexual manners,offcourse, but would be a good help for zaping the whole HIV/VD issues in the first, finally for FREE.