Which object is the farthest human-made thing still operating?

Voyager 1 holds the record as the farthest human-made object still functioning. It has traveled beyond the heliosphere into interstellar space and remains in contact with Earth through NASA’s Deep Space Network. Its distance from Earth is measured in tens of billions of kilometers, over 160 astronomical units. Despite its age, engineers continue to manage limited instruments and power resources. This makes Voyager 1 both a scientific probe and a symbol of human exploration.