Planet

A planet is a extraterrestrial body orbiting a star or stellar remnant that is massive adequate to be rounded by its own gravity, not massive enough to cause thermonuclear fusion in its core, and has cleared its neighbouring region of planetesimals.

After stars and stellar remnants, planets are a few of the most massive objects known to man. They play an important part in the structure of planetary systems, and are also considered, along with large moons, the most feasible environment for life. Thus planetary science is crucial not only to comprehend the structure of the universe, but also to better understand the development of life, and to aid the search for extraterrestrial intelligence. Additionally, the planets visible from Earth have played a vital role in the shaping of human culture, religion and philosophy in abundant civilisations. Even today, many people continue to believe true the movement of the planets affects their lives, all though such a causation is discarded by the scientific community.