comets are members of the solar system; that is to say, they travel in orbits around the sun in a manner fundamentally the same as that of the planets, the asteroids, and meteors. many appear regularly . one, Encke's comet, returns every three years, while others are calculated to return at invervals of thousands of years. Some suddenly appear in the sky or are calculated through a telescope as they approach. They travel in a curved path around the sun and disappear again in the recesses of the solar syatem, far beyond the range of observation.