It never rains but it pours for Space Brothers unlucky protagonist - quite literally in this case, as both his and Team E's hard work in the so-called Comeback Competition is suddenly thrust into peril on account of some rain showers.
Although all of the rival teams remain confident in their designs, the use of sponge tyres by Mutta and company poses a very real possibility of their rover getting bogged down in the mud as a result. Thus, the race is on to find a solution before their shuttle launches, meaning that Mutta and Serika have to race back to the hotel in the hope of finding something suitable to fix their current problem.
Thankfully, and with some help from the hotel janitor, Mutta finds exactly what he needs - some silicone bathroom sealant, which has all of the properties required to fit in with the team's existing design while protecting those tyres from the elements. With their solution in place, all that remains is to see how the overall design fares; although they don't emerge victorious - that prize ultimately goes to a surprisingly familiar face - they still chart second amongst the teams of ASCANs to make a quite literal comeback in their training.
For all of its occasionally frustrating deviations, this final episode was a hugely enjoyable end to this particular story arc - there's something thrillingly simple about watching a group of would-be astronauts running around trying to solve an engineer problem, and then seeing how their proposed solution shakes out. It's also the kind of thing you simply don't see in anime traditionally, which serves as a reminder as to just how refreshing watching Space Brothers is most weeks, in turn explaining just why it's such an enjoyable watch most weeks. It doesn't feel like I've been watching this series for sixty weeks now (or almost thirty hours, for that matter), but I'd be more than happy to see it go on for another year and beyond.