After watching a few clips on the meteor rain in Russia I had been thinking.. [video=youtube;vKpMaeN5fyI]http://www.youtube.com/watch?v=vKpMaeN5fyI[/video] Doesn't all this material coming from space add to the gravitational force of the earth? If that is true, after some time isn't Earth going out of orbit or crushing with an other planet?
An unverified source says that Earth collects in the order of 100,000 tonnes of material from space every day. That's a lot! But it's actually negligible compared to the mass of Earth, which is about 10,000 billion billion tonnes. At that rate of accumulation, the Earth's mass will have increased by 0.002% in five billion years, when the Sun has gone red giant and the Earth is a lifeless glob of boiling lava. So, no... The Earth's gravitational force isn't noticeably affected by added material from space.
The material that falls into Earth everyday as pointed out to you has little effect on our orbit. However, to your larger question, planetary orbits are stable for the short term. But longer term, planetary orbits will be chaotic. For the next few billion years Earth’s orbit should be fairly stable. If you are looking to stay around for longer periods, you might have something to worry about. And things are going to get a bit hotter on Earth with the Sun warming up and expanding as it burns the last of it hydrogen fuel. http://en.wikipedia.org/wiki/Stability_of_the_Solar_System So near term, planatary orbits are stable, longer term, not so much.
In addition to the fact that the amount of matter added to the Earth is negligible, even a large change in the Earth's mass would have hardly any effect on its orbit. If the Earth's mass were to suddenly double, its orbit would shift only by an order of 1000 km or so. This is because it is the mass of the Sun, being some 333,000 time larger, that predominately determines the Earth's orbit.
Most of these objects, are orbiting the sun in their own, relatively stable orbits - in the same direction as earth. So when two objects that are both orbiting the sun in the same direction collide, the result is an object still orbiting the sun just fine.
There is a change (abouth 1% in the next 5 billion years) mercury could in the long run could either be captured or inpact on either Venus or Earth http://en.wikipedia.org/wiki/Stability_of_the_Solar_System
it's a russian joke thing...it came from a video of a guy in Vladivostok driving recklessly. The original saying was: "Nu nihuya on ohuel" which roughly translates to "The ****ng **ck did he **ck up", he basically saying "**cking, **ck". http://www.youtube.com/watch?v=2Wmj0Xi84Cs is the original video, unfortunately the original source is now gone =/