What comets are made of?

In order to understand what are comets made of, we need to break down the three main parts of the comet: the nucleus, coma, and tail. Comet nuclei are known to range from about 100 meters to more than 40 kilometers across. They are composed of rock, dust, ice and frozen gases such as carbon monoxide, carbon dioxide, methane, and ammonia. read more

The comets of long duration have their origin from the extra solar nebula, a spherical shell of material at the outside edge of the solar system known as the Oort Cloud. Short period comets, therefore, have trajectories mostly in the plane of the solar system, while long period comets might come from any direction. read more