The space race has been a bit like the logic of the media. Once the problem of traveling to the Moon has been solved, and executed the prodigy a few times, NASA, the Soviets and those who would come later forgot the subject easily and repeatedly. Neil Armstrong took a small step for man and a great step for humanity when he stepped on the Moon, but of the other astronauts who did it later they only remember at home.
The first missions to the Moon traveled to its visible face. It was logical: there would be subsequent missions that landed on the dark side. But there were not, because once tired of the space race, and exhausted the budgets that the bipolar leaders were willing to dedicate to it, the matter stopped making sense. Political sense, it is understood. The scientific interest of the Moon remains intact in our times, almost half a century after Armstrong placed his boot on our satellite.
The great problem to explore the hidden face of the Moon does not belong to the genre of astrophysics, but to that of telecommunications. Richard Nixon would not have been able to talk to Armstrong if it had landed on the hidden side. Worse still would be the situation of a rover or a robot that poses there. Armstrong, after all, could have managed with his own criteria of military, but the robot would not know what to do before an unforeseen event. It would be as dark of terrestrial radio broadcasts as we are on that side mentioned by the famous song.
So that the engineers of the Chinese space agency can send instructions to the ship for the landing and the exploration, it has been necessary to send in advance another satellite, Queqiao, that since June has been in an orbit beyond the Moon, from where it can see the hidden side, and also receive the lunar robot data and transmit it to Earth.
Chang'e 4 will obtain valuable data about the geology of the hidden face, which we already know is not the same as the visible one. It will also carry silkworm eggs and potato seeds and flowers there. Maybe one day we will need all this to survive there.