Comets traverse the Solar System until they collide or evolve and break up in the main asteroid belt
Generally speaking, scientists think it goes round and round the solar system until it bumps into something, something big like a planet. Although we have recently noticed that some asteroids and comets end up colliding with each other, when they do, both courses are altered. And sometimes one or both are completely destroyed by the impact.
We observed the impact of Comet Levy with Jupiter, and we are currently observing a comet heading towards the Sun in 2010. We also observed a comet hitting an asteroid, demolishing the asteroid, and in this case the comet seemed to stay quite close to its course original. . For those who think they can shoot down an asteroid or comet, this poses a pretty big problem. If a comet and an asteroid can collide at such a great speed, and one can keep going, then we might have a problem using kinetic missiles to try to take out a comet.
In fact, there was another great article on SpaceWeather(dot)com titled “Comet Dipped Into the Sun” published on October 20, 2010 that said, “A newly discovered comet is dipping toward the sun. Chinese comet hunter Bo Zhou found it on Oct. 19 in SOHO coronagraph images. The comet is faint now, but should brighten in the next few hours as it warms up.”
There is another potential eventuality, and there has been some debate and research work on this, namely when a comet decays in its orbit or hits something that slows it down, it could retreat and then re-enter the asteroid belt and like a horse racing. he grazes. Of course, as it passes through the asteroid belt, it could collide with an asteroid and put it into a new Earth-crossing orbit.
Comets are very interesting things to study, as are asteroids, and while NASA is planning a manned mission to an asteroid, you may want to do some more personal research on this topic. So please consider all this.
References:
1. “Comets: Creators and Destroyers” by David H. Levy, Touchstone Publishers, a division of Simon and Schuster, New York, NY, (1998), pp. 256, ISBN: 978-0684852553.
2. “The Menace of Comets and Asteroids” by Gerrit L. Verschuur, Oxford Press, New York, NY, (1996), pp. 237, ISBN: 0-19-510105-7.
3. “Red Doomsday Comets and Asteroids – the Million Megaton Threat Thing Life on Earth,” by Duncan Steele (foreword by Arthur C. Clarke), John Wiley and Sons, New York, NY, (1995), pp. 308, ISBN: 0-471-30824-2.
4. Research Paper: “Evolution of Comets into Asteroids” by PR Weissman, WF Bottke Jr., HF Levinson, published in Asteroids III pp. 669-686, 2002.
5. ASD News Online – October 20, 2010 article titled; “When a comet isn’t a comet – Rosetta finds out – Two asteroids in the wrong place at the wrong time” (source; ESA).