What is the difference between a satellite, a planet and a star?

The names of stars, planets and satellites are all invented by human beings, but they are different in terms of constituent elements, formation and evolution, operating rules, mass and volume. Planets are a general term, and most large independent objects in space can be called planets. Generally speaking, stars are planets that emit light and heat by themselves, and most of them are composed of light elements such as hydrogen and helium. A satellite generally refers to a planet that revolves around a certain planet.

The difference between a star, a satellite and a planet is that a star is like a grandfather, a planet is like a father, and a satellite is like a son. They interact and depend on each other. Stars can emit light and heat, planets are generally solid or liquid, and satellites are generally solid. Planets revolve around stars and satellites revolve around planets. Stars are huge in size and mass, far exceeding planets and satellites. Stars can produce nuclear fusion, light and heat, and provide clean energy. The difference between the three is very big.

Due to the action of gravity, matter in space keeps gathering. When the mass of the aggregated matter reaches the critical point that can trigger nuclear fusion, the matter will be ignited to form a star, while the less mass matter will form a gaseous planet. The most abundant substances in the universe are light elements such as hydrogen and helium, while other heavy elements are formed by nuclear fusion and supernova explosion.

Rocky planets like the earth are heavy elements, which have gathered a large number of stars, nuclear fusion and supernova explosions into space. Young stars like the sun also contain more heavy elements than the earth, but they account for a small proportion of the total mass of stars. The solar system was formed not long ago. Before the formation of the solar system, other stars had formed and exploded, so all celestial bodies contained heavy elements.

Planets revolve around stars, satellites revolve around planets, and planets and their satellites revolve around the center of dense galaxies with stars. Most stars have planets, but planets may not have satellites, but it is difficult for satellites to have their own satellites, because the planets around them are heavier and may have greater gravity on microsatellites, so microsatellites are unstable and eventually pulled into the satellite orbit of the planet.