Which of the following is NOT a component of a planetary system?

A planetary system consists of various celestial bodies that are bound together by gravitational forces. The primary components typically include a star, which serves as the central body, alongside various planets that orbit this star. Comets are also part of the mix, as they are small, icy bodies that can originate from regions within a planetary system, such as the Kuiper Belt or the Oort Cloud.

Clouds, while they may exist in space, particularly as interstellar gas and dust or within the atmospheres of planets, do not qualify as a distinct component of a planetary system. They do not hold the same gravitational relationships or structured orbits that characterize the other components like stars, planets, and comets. Therefore, while clouds can be found within a planetary system, they do not constitute a component of the system itself. This distinction is why clouds are identified as not being a component of a planetary system.