Headscratchers / Black Mirror: Beyond the Sea

• Why did NASA send the live astronauts to space instead of replicas? Well, there are a few possible factors, like they might require extensive maintenance. Still, humans also have a lot of requirements. Is it some sort of Artistic License – Space?
  • A lot of people have pointed this one out. Justifications that have been put forward include:
    • There's always the possibility that the link between the human and the replica will be lost due to a technical fault. If the human astronaut's in space at least the mission can be continued whereas if the replica's up there the mission is ruined and all the time and money used to set it up is wasted.
    • The astronauts take off anything metal they're wearing whenever they exit the ship to perform maintenance so the replicas wouldn't be able to run the mission on their own because they're mechanical.
    • It's implied early in the episode that the purpose of the mission is to test the effects of being in space on the human body so the biological astronauts have to be the ones up there:
      David: The human experience, the survival of the human body and life, that's really central to the mission.
• Are there no therapists in-universe? It seems that nobody consulted on David's mental health, didn't provide any sort of counselling to him or tried to make the most basic attempt at monitoring his state. While doing a long-term space flight mission. And it only escalates when the option to switch replica with Cliff is apparently purely his and Lana's private decision, not consulted with anyone. While it allows to cut on the filming budget, it makes the premise just plain weird, where no expenses were spared to provide with elaborate spaceship and human-like androids, but apparently having a regular shrink on duty - like we do in real life - is too much to ask.
  • You do indeed have to wonder what NASA or whatever space agency Cliff and David work for are doing for most of the episode. Cliff makes a reference just after David's family is killed about speaking to ground control and being advised to just let David be for the time being but then they're never mentioned again. Once Cliff starts to worry about David being suicidal you really would think he'd be speaking to the people they work for about his concerns and that they'd be stepping in to provide emotional support. I think we just have to suspend our disbelief for this one. Scenes involving David getting external support would be a distraction from the story the episode wants to tell about the personal relationship between Cliff and David and Cliff's family by extension.
• Why are there only two astronauts on this mission? Given that the spaceship requires two people to operate, it defies all principles of safety and redundancy (which is especially critical in space) to not have an extra crewmember or two in case someone becomes incapacitated or dies — especially since they'll be unreachable for six years.
  • As previously established, the mission is primarily about studying the effects of space on the human body. Since the station is largely automated, a larger crew would either be redundant (since one astronaut could serve as control, one as variable), or it's possible there are other space stations out there with different crew numbers to see different results.
• How does the link function instantaneously between Earth and what is presumably interplanetary space? There should be a delay of seconds to minutes, due to light speed being finite, making it impossible for the replicas to react in real time to the astronauts' consciousness. It could be assumed that the link somehow transmits the entire consciousness of the person, and that the replicas are then functioning autonomously; but this would seem to be contradicted by Lana's comment that David is "wearing" her husband as a suit, implying a real-time link. Not to mention all the philosophical identity problems posed by the replicas' consciousness developing separately from the astronauts', then somehow being "synchronized" with it (effectively killing the replica as a personality).
  • Black Mirror frequently plays fast and loose with the limitations of technologies when utilised in specific scenarios, like the digital clones in USS Callister retaining the memories and full personalities of their human counterparts despite being grown from their DNA. You're just supposed to accept it as a break from reality to allow the story to happen.