He might have acted as cool as a cucumber in front of his younger brother while discussing Hibito's panic disorder, but as you might expect beneath the surface Mutta was far more concerned than his demeanour may have suggested. The result is a sleepless night of thinking and research, although ultimately his final decision is that Hibito's issue isn't as serious as it might otherwise have been.
In the midst of all of this worry, we've missed out on one rather important element of Mutta's life, that being his (as well as Kenji and Nitta's) meeting with Butler to discuss their futures. This is perhaps glossed over a little because we were already all-but certain as to how this would pan out for Mutta after his NEEMO training, and lo and behold Mutta is indeed selected as the name Japanese man to enter space. First up though he needs to gain experience by being part of a backup crew, which leaves his shadowing Vincent bold - a tough task, particularly when your first day on the new job is carried out with no sleep.
With that out of the way, we get to spend a little time pondering the futures of Kenji and Nitta as they receive the news that they haven't made it - a decision that Kenji in particular was prepared for, but one that still leaves him questioning his resolve and whether he was right to even try becoming an astronaut at all. Such thoughts are short-lived however, as both Butler's words and their next training tasks suggest that space, and perhaps even the Moon, still aren't all that far away for either of them, allowing them to pick themselves back up and continue in their particular quests.
It's this ability to look at the what an event means for characters beyond our titular pair of brothers that adds to Space Brothers ability to be enjoyable and interesting week-on-week - so many shows would ditch secondary characters the moment they've been "defeated" by a protagonist, but this series insists upon continuing to follow their journeys regardless, and is all the better for it. After all, how an individual reacts to failure tends to be far more interesting than how they react to success, and it's a philosophy clearly shared here in how it apportions in time to provide a breath of fresh air from a show with no shortage of them.