Comets
comet
Comets are just very icy asteroids, they become comets when a large enough of a body of mass, i.e. jupiter or saturn. When this happens, the asteroid gets thrown into an extremely high elliptical orbit. They ideally have an orbit perpindicular to the ecliptic.
These are comets. They are usually in very eccentric orbits around the sun, spending most of their time way out beyond the orbit of the outer planets. Here it is cold and they have no tails. They are also very difficult to detect here as they are quite dark, small and the distances are large. As they orbit closer to the sun the surface heats up, and the ice vapourises. Two tails are often formed, a gas tail which points directly away from the sun, effected by the solar wind, and a dust tail which is left behind in the path of the orbit.
A small icy object that can have a tail up to 10 million kilometers long is a comet. Comets are composed of ice, dust, and rocky material, and when they approach the Sun, the heat causes their icy components to vaporize, creating a glowing coma and a spectacular tail that always points away from the Sun due to solar wind and radiation pressure. This tail can become extraordinarily long, sometimes extending millions of kilometers into space.
An icy object in space is often referred to as a "comet." Comets are composed of ice, dust, and rocky material and typically exhibit a glowing coma and a tail when they approach the Sun. Other icy bodies in space can include "ice moons" and "icy asteroids," which are primarily made up of frozen gases and water ice.
comet
That description could fit any number of bodies in the solar system, but generally "asteroid" might be closest. Other more distant objects such as comets or Kuiper Belt Objects would tend to be more icy than rocky.
Pluto, now no longer considered a planet, is part of a collection of icy objects called the Kuiper Belt, which orbit the sun beyond Neptune. Beyond the Kuiper belt are a few object scattered into extremely large orbits. The most notable of these is an object called Sedna. Beyond Sedna there may be an even larger collection of icy objects called the Oort Cloud.
The largest object beyond the orbit of Neptune is Eris, a dwarf planet slightly larger than Pluto. Eris was discovered in 2005 and is part of the Kuiper Belt, a region of icy bodies beyond Neptune.
Small icy bodies are located in the solar system where they orbit the sun.
comet
a comet