Wedge
The universe is the general term for all things in the world.
The universe is boundless, with no end in time or space.
Earth is our home and the third planet in the solar system.
The solar system is settled on one side of the great spiral arm of the Milky Way.
The Milky Way is like a drop in the ocean in the vast universe of galaxies. There are countless celestial systems like the Milky Way - the world we live in - throughout the universe.
Among them, a distant galaxy called "Xuantian" is 10 billion light-years away from the Milky Way.