Could a comet, periodically returning to the Sun, keep its appearance unchanged forever?

Not. With each approach to the Sun, the periodic comet becomes weaker and weaker. And there are those who “cannot withstand” more than two or three approaches to the Sun and, decaying, give rise to a meteorite swarm that continues to move in the old orbit. When a meteorite swarm meets the Earth, we observe a meteor shower.

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.