It's 2075 and space exploration has made decent advances. A moon base has been established and preparations are being made to send a manned mission to the moons of Jupiter. Hachirota Hoshino, a.k.a. Hachimaki, on the other hand is a garbageman in space. Well, sort of. He and the crew of the spacecraft Toy Box work in a department of Technora, a space exploration company, and their job is to collect orbital debris left from now common space-flight ranging from small screws to satellites. The job is dangerous and not very respected, but someones gotta do it. But Hachimaki isn't without ambition as he dreams of owning his own spaceship.
The rest of the Toy Box crew consists of Captain Fey Carmichael, the brash but well meaning american captain of the Toy Box and Yuri Mihairokov, the silent and stoic russian who lost his wife in an accident when a screw collided at high velocity with the low-orbit aircraft they were traveling in. Hachimaki later decides to join the Jupiter mission and a new member of the crew is introduced, Ai Tanabe, who is trained to become his replacement, though they definitely have strong philosophical differences.
In the meantime, space exploration and the Jupiter mission in particular is also being endangered by the Space Defence Front, a terrorist organization that wants to prevent further advances away from earth. Brewing political conflict on earth and the danger of orbital warfare is also not helping.
Planetes is a very good but somewhat short hard sci-fi series. It paints a pretty good picture of what the near future of space exploration could look like as well as making some philosophical and political points about what this could mean for the rest of humanity as well as for the individual working in space. It has also been adapted into an anime series which has a few significant changes, e.g. making the Toy Box crew into a full fledged department of waste disposal and adding a load of characters to it as well as introducing Tanabe much earlier. Though sticking very closely, the anime does a lot of filler which ranges from very good to rather bad, depending on the episode. It also doesn't finish off the series which was still running when the anime was being produced. The anime pretty much omits all of the last of the four volumes (which has been split up into two volumes in some countries).
I for my part prefer the manga which I could read over and over again. The characters are very well fleshed out and the stories, usually contained within a chapter or two while still tracing an overarching plot, are always enjoyable and interesting. The technology that is presented is also believable to be possible in the next 65 to 70 years, though the anime has also one-upped this a little bit (without going overboard).
Planetes is one of my favorite mangas I have read so far and while I have heard it being mentioned on the show sometimes, I am not sure how Rym and Scott have enjoyed it or if they have only seen the anime. I'd also like to hear if someone else in the forum has read the manga or seen the anime. While they are comparable, they are certainly not a 1:1 adaption and I would recommend experiencing both.