What astronomical fact testifies to the constancy of the structure of the solar system?

The condition for the constancy of the structures and functioning of systems is the frequency of movement of their components. The motion of the planets and other bodies of the solar system is periodic; it has been stable for several billion years.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.