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How do asteroid orbits differ from comet orbits?
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Solar system
The planets (in comparative size) in order of distance from the Sun.
Asteroid and comet orbits differ significantly in their shape, stability, and orientation within the solar system.
Orbital Characteristics
- Asteroids: Most asteroids occupy the asteroid belt between Mars and Jupiter. Their orbits are generally shorter, more stable, and fairly circular compared to those of comets.12
- Comets: Comets typically follow highly eccentric, or elongated, orbits that carry them from the outer reaches of the solar system to close passes by the Sun. These paths are often erratic and can be highly inclined relative to the ecliptic, the plane of Earth's orbit.134
Classification and Dynamics
Astronomers often use the Tisserand parameter to distinguish between these bodies; asteroids generally have values greater than 3.0, while most comets have values less than 3.0. Furthermore, while asteroids are largely confined to stable regions, many comets travel in unstable, planet-crossing orbits.42
Comets are further categorized by their orbital periods:
* Short-period comets: Often originate from the Kuiper belt and move in prograde, less-inclined orbits.43
* Long-period comets: Originate from the distant Oort cloud and arrive from all directions with random inclinations.43