Is there a planet closer to the Sun than Mercury?

A planet whose orbit would be entirely within the orbit of Mercury has not been detected. However, the minor planet Icarus at perihelion is closer to the Sun than Mercury. At this time, its distance to the Sun is only 0.19 astronomical units.

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.