You know how some kids dream of being an astronaut when they grow up? That's Chuck. He's brave, dashing, confident and, unlike most people, looks good in a big, puffy, white spacesuit. When his school guidance counselor questioned whether he was smart enough to be an astronaut, Chuck replied, Of course, it's not rocket science, until his guidance counselor reminded him that no, actually it is rocket science. Chuck's adventures on Planet 51 net him a new friend in Lem and a new view on interplanetary life: space aliens are people too.
Rover is part space exploration robot, part Labrador retriever. If you like your pets to have petroleum gas sensors, then Rover is for you. If you want a cute companion that can fetch your slippers and collect carbon nanomaterials for spectrometer analysis, Rover is your guy. He loves being tickled on his undercarriage and transmitting complex scientific data back to Earth. While he might not be as warm and furry as a real dog, he's a lot easier to pick up after (if you know what we mean). He works for Chuck but becomes Skiff's loyal pet, proving that while dogs may be man's best friend, robots have better taste in owners.
Lem is a nice, typical kid. he's never late, does his homework on time, and always drinks his Galactic Goo from a glass, not from the container. On the surface he's a shy geek, but beneath the green skin beats the heart of a hero. Some kids are born great, some have greatness thrust upon them. In Lem's case, he has Chuck thrust upon him. It might seem like a bad deal, having to help this weird, loud alien guy in the funny spacesuit find his rocket so he can return home, but hey – it's a lot more fun than trigonometry class. And in the process, Lem learns about courage, loyalty, sacrifice, and himself.
Neera is your typical girl next door: smart, pretty, with clear green skin and the cutest, cuddliest sensory antenna poking out of her forehead. But don't be fooled by her demure looks. Neera speaks her mind, and on Planet 51 everyone has a jumbo-sized brain so her mind is really loud. Neera is like a lot of girls her age: she's torn between being a rebel and playing it safe. And if you tell her what to do or who to hand out with, well, let's put it this way: you won't want to be you. Okay, Neera's tougher than she looks but that doesn't mean she doesn't have her soft, mushy side. She likes Lem. And the great challenge of her young life is to figure out weather she should act on her feelings or stay the most fiercely independent girl in the eleventh grade. Oh, to be 16 again!
Poor Skiff. First, his name is Skiff. Kinda weird. Second, he's Lem's best friend, which wouldn't be a bad thing if Lem was a really cute girl who was into conspiracy theories about alien life and government cover-ups, but Lem is Lem so Third, well, there are a thousand other things we could list so let's cut to the chase. Skiff is looking for that special someone who loves and understands him. The good news is that he finds that special someone. That bad news is that special someone is a robotic exploration vehicle named Rover who is his best friend. Sure, it might seem a little strange that outside of Lem, Skiff relates best to a six-wheeled mechanical space probe with titanium panels instead of skin and an alpha particle x-ray spectrometer instead of a heart, but hey, when you find a good friend, you have to stick with them.
Eckle is a 7-year old kid on Planet 51. He's obsessed with monsters, aliens, sci-fi films, and comic books. Hmm come to think of it, Eckle sounds a lot like a 7-year-old kid on Planet Earth. And that's the point. Everybody knows an Eckle. You probably have one living on your street. Or you might be an Eckle. Look for these signs: Always shooting your toy gamma death ray at the neighbor's cat. Imitating the screeching cries of a Martian Cosmonaut as he's obliterated by solar storm radiation. Tirelessly debating the engineering merits of a Remulackian Rover Vehicle versus a Niburian Utility Probe. Yep, it's a dirty job but somebody has to do it. Just please don't do it when you're sitting behind me at a movie theatre.
Glar is one of those guys who protests about everything except the most annoying thing in the universe: himself. He's got long hair, never met a slang word he didn't like, and the only good thing about his constant guitar playing is at least he didn't choose to play the tuba. Glar goes to school with Lem and Neera and can't figure out why Lem doesn't think he's cooler and Neera doesn't think he's cuter, although it's amazing they can think of anything above the shrill din of Glar's singing. Yeah, Glar is a bit of a pain but deep down his heart is in the right place: behind his left kneecap like everyone else on Planet 51.