Dick is $$20$$ years old when he takes off on a space voyage at a speed of $$0.80$$ $$c$$ ($$c$$ is the speed of light) to a star $$20$$ light-years away. His wife Jane, also $$20$$ years old, decides to wait for him to come back after successfully completing his mission. Finally, after $$30$$ years of voyage in his reference frame, Dick comes back. How old is Jane upon his return?