"solar system"

In our universe, whether as large as a galaxy or as small as an electron, we are always in motion, and even when we think we are sitting motionless in our chairs, the earth is carrying us around the sun at a speed of about 30 kilometres per second, and the sun is also in motion, in fact it is carrying the entire solar system around the centre of the milky way, and at a speed of about 220 kilometres per second.

Although the Earth is just a "grain of dust suspended in the sun" in the universe, for us humans, this "grain of dust" is irreplaceable.

The milky way is a huge galaxy with hundreds of billions of stars, and the sun is just one of the less prominent stars that, along with many other stars in the galaxy, orbits the centre of the galaxy.

In the macroscopic world, the solar system is a system of celestial bodies centred on the sun, in which the vast majority of mass is concentrated and the major planets orbit the sun, while in the microscopic world, an atom is a microscopic system centred on the nucleus of an atom, in which the vast majority of mass is concentrated and electrons orbit the nucleus.

The solar system is located in a region with a stellar density of only 72 million parts per million of the highest stellar density region in the Milky Way, which is a remote and inhospitable part of the galaxy.