Being surprised at how averagely rated this is here, I wanted to write a review. First of all what I found negative was the animation style, which doesn't fit the story as such (The setting is a very realistic one, but the animation doesn't necessarily fit the realism), but considering the time it was aired, it is alright. Especially the Plasma animation ticked me off, as Plasma is NOT a normal explosion (which is glowing gas expanding at a rabid rate). It is a state beyond the gaseous form, and if it does emit light, it is within frequencies that we can't see, but it is NOT orange. Also the spacecraft had some weird features, but well it has to look cool doesn#t it?
Now to the story. Comets, Asteroids, and Meteors have been considered a threat for a long time now (for about 50 years now) and now they're attempting to calculate the movement of all of them. That being applied to an anime is pretty good. While it does have relation to Planetes (space garbage is a more recent problem), I don't think that you can really compare the two. The story covers backgrounds and the characters well enough, and also explains the developments. While I was thinking of giving the entire show a score of 8, the interrogation scenes tipped me of into the other direction. They are very well made.
The music fits perfectly into the show, and even the ending insert song emphasized what I was thinking from the ending scene.
The character definitaly are a huge plus to the show, each showing unique traits and a great development. I loved the cat, Admiral, and the four Otakus, while the somehow stoic Karin also lightened up the entire show.
All in all I think it is one of the few very good series dealing with realistic problems.