That "walking pace" stat could be very impressive if it were given with the proper qualification information.
For example, if it could detect an object moving at that pace over the course of a year at 1 light year away... I would probably not be as impressed if it could do it from 50 light years in a matter of minutes.
It is contrary to reasoning to say that there is a vacuum or space in which there is absolutely nothing. -- Descartes