Since this is a very short anime and there is only one important matter to discuss about it, I'll keep my review short as well. There is no doubt that Planetarian is absolutely top-notch in the graphics department, audio is also good. The setting is interesting, though not very original, we've seen it all before - and not just once. If the story was equally good, this show could have a really nice score, at least 8/10. Unfortunately, it fails at the most important part.
What is that important part, then? It's the revolving question of how human Yumemi actually is. Key isn't trying to reinvent the wheel here, ever since Blade Runner works regarding the humanity of androids keep popping up. There usually are some slight suggestions that, despite being artificial constructs, androids aren't actually that much different from humans - even to the point of having a soul, if you believe such things.
Unfortunately, this is where Planetarian fails. Not once within the 2 hours or so of the show have I felt like Yumemi is anywhere close to a human. I have not played the VN, maybe she is portrayed better there, maybe more time was required to show the human part of her, but I'm judging the anime version alone... And there, she is just a robot. That's it. There is nothing human about her, she is acting according to her programming at all times, and that is unforgivable in an anime that is trying to tackle this subject. Yes, she is cute, she is adorable and fun, and her death was crushing, but it's the same kind of sadness I'd feel if a tree fell on my car during a storm. I have felt that the MC also thinks this way. He hadn't really started personifying her, he just considered her as the last link to the lost world and that was what he was mourning in the end - he definitely wasn't mourning Yumemi as a human being. Maybe I'm wrong about him and the upcoming movie will prove it, but as of now, that is my opinion.
I have actually rated Planetarian 8/10 at first, since I have enjoyed if quite a lot, but when I thought about it a bit more while writing this short review, I couldn't help but start thinking it by no means deserved such a score. I think the most objective score would be 6/10, but since it's a Key anime and I'm a fanboy, I should rate it 7/10. It's short and it's definitely not a waste of time, but IMO it fails in the most important department. If Yumemi had a lot more screentime, it might have helped her case.
Or well... maybe I'm completely wrong and the writers weren't trying to make her look human. In that case, they've succeeded.
