This seems to be a problem with my mission generator, which should place astronauts on the map in random places and show them the path on the minimap - I did it on the residual principle, and it seems that it sometimes places the astronauts too far away from the player. In general, this is normal, I myself sometimes lose several spaceships before I get to the astronaut :-)
I planned to make a dynamic mission system, where the mission controller will alternate between different missions: exploration, attack, rescue and defense depending on the situation in the game, but I did not have time to finish this part of the game as planned before deadline :-(