Space is a native thought, that looks outside planet earth, and as such to 'communicate' requires a specific [ not Pacific ]passage to ensure radars are not blocked nor imagery distorted or slowed.

To deliver on horse back required an animal to be nurtured such as a horse, and a station where riders could rest, feed, gather, talk and be assured of a communication.

 

Sure we have provoke the thought of Mars and the Moon, though the dimension of space, if only thought of a corridor may leave our solar system without any further understanding of the reason why our first reference of communication, the Sun ( observer®️) may be a system of logistics rather than exploring real science.