The Propulsions all having fiery red hair makes sense because of the urban legend that redheads are aliens.
You ever wonder why Sean packed specifically peanut butter sandwiches in "Sean's Year In Space"? Well, scientists at the Jet Propulsion Laboratory (who helps out with the show), keep a can of peanuts in the room as a good luck charm. So, Sean packed peanut butter sandwiches for good luck.
You know how Sean's eye color is never consistent? Apparently, green eyes can sometimes appear gray or blue depending on mood and the weather.
In One Small Step, Sean is actually excited to go to space for once, while Sydney is more hesitant. It's almost like their personalities were switched. Why is that the case? Sean is known for absolutely adoring Neil Armstrong and the Apollo 11 mission in general. Since the kids planned a sleepover on the moon to celebrate the 50th anniversary of the moon landing, of course Sean would be excited. Plus, when you take into account his Character Development of him being less afraid of going to space, it makes perfect sense. As for Sydney, she is noted for basically being like everyone's big sister and protective of her friends. She's also unsure of Jet's crazy plans from time to time. Jet building a super saucer by himself with the intent to fly it to the moon without adult supervision is definitely concerning, especially for an almost mother-like figure like Sydney. It makes sense that she's hesitant.
In "Zerk Visits Earth", the gang shows Zerk the wonders of apples. Why apples specifically? They're the state fruit of Washington, where the show takes place.
When Jet 2 and Sydney 2 appear side by side, Sydney 2 is sleeker and cleaner than Jet 2. Sydney built her robot clone with the help of her mom, who is an experienced robotics engineer. Jet 2 was built by Jet himself using junk from his garage, and Jet is known to be very reckless and impulsive, plus he's only a kid. That's why Jet 2 looks very rusty and old compared to Sydney 2.
In "Galileo, Galileo!", the kids wear Italian renaissance hats to help Sean with his report on Galileo. Sean, Sydney, and Mindy all wear purple hats, while Jet wears a green one. Jet's green hat highlights that he's different from the rest because he's an alien and not a human, plus it highlights his quirkiness.
Jet is an idealized version of Sean, Sydney, and Mindy combined, harboring all their positive traits. Jet shares Sean's intelligence, Sydney's creativity, and Mindy's curiosity. He's benevolent, talented, and wields futuristic technology from alien planets. Since he's from space, he offers a unique perspective about Earth to the other kids, and his optimism makes him the perfect playmate for Sean, Sydney, and Mindy.
Boxwood Terrace is barely covered in snow, as shown in winter episodes like "Holidays in Boxwood Terrace", "Endless Summer", and "Our Sun is a Star". This could be chalked up to lazy rendering, but Mindy reveals in "Freebird" that Boxwood Terrace doesn't get much snow in winter, explaining the lack of snow.
Mitchell appears to be Mr. Peterson's personal mini-me. Mr. Peterson has a white polo shirt with a yellow sweater vest on top, and khakis. Mitchell has a white polo shirt with a red jacket, and khakis as well. Mitchell's jacket is an inversion of Mr. Peterson's sweater vest. His sweater vest is yellow with red cuffs, while Mitchell's jacket is red with yellow cuffs. Mitchell is also a mini-me in terms of personality. Like his father, he is very snooty and egocentric, with anger issues. It seems that they're not so different after all. Mitchell's drive to become a detective and sense of entitlement combined with Mr. Peterson's pushover tendencies makes for a very strained relationship.
None of the kids have siblings, making them all only children. Why is that? If Jet, Sean, and/or Sydney had siblings, they'd all have to deal with them begging to be taken to space, especially the younger ones. Plus, Mindy already fills the role of the little kid who wants to tag along, and in many ways, acts as a metaphorical younger sibling to Jet, Sean, and Sydney.
Mitchell is a snarky loner, yet he has a pet dog instead of a pet cat. This is because Mitchell is a detective, and dogs can sniff out clues. Plus, dogs are energetic and provide a contrast to Mitchell's cold persona, though Cody is very lethargic.
Mitchell's checkerboard bomber hat might remind some of the stereotypical plaid deerstalker hat associated with detectives, particularly from The Gay '90s. However, his Leitmotif is jazz, which is more associated with film noir from the '40s and '50s. This provides a clever contrast between different eras of detectives that both make up Mitchell's personality.
In "Sunspot's Night Out", the neighborhood animals perform "Ode to Joy". Ludwig van Beethoven's Symphony No. 9 was based on a poem. The final lines to the original poem are translated as "Seek him above the starry canopy! / Above stars must He dwell." Considering that "Sunspot's Night Out" is about constellations, the use of Symphony No. 9 suddenly becomes meaningful to the context of the episode.
Fans bemoan Mindy's Idiot Ball moments in Season 2, but it's entirely possible that she was pretending to be an idiot. An overlooked line from an early Season 1 episode, "How Come the Moon Changes Shape?" reveals that Mindy did know that there's only one moon, and she just likes making the big kids explain over and over. This means that Mindy thinking that the Sun revolves around the Earth in "Galileo, Galileo!" could have been Obfuscating Stupidityfor kicks.
It could also be the Fleeting Demographic Rule: The target audience for RJG! is going to outgrow it eventually, so they probably retaught certain topics for the newer audience.
Jet also tends to forget stuff. In this article, Craig Bartlett says that the Propulsions all have a short-term memory, which explains why Jet sometimes forgets things he already learned.
The reason why Face 9000 is Out of Focus in Season 2 might be because the kids are learning to become independent thinkers, figuring stuff out by themselves instead of just asking grown-ups for the answers. Given that Face 9000 is desperate for someoneto pay attention to him as shown in "Moon Face" and "My Three Suns", he likely realizes this and is disappointed that he can't teach the kids anymore, thinking he has outlived his usefulness.
If the kids didn't perform that musical number to justify why the Propulsions should stay on Earth, the Propulsions would have never gone back to Earth, which means that Sydney and Sean would be stuck on another planet in another galaxy for the rest of their lives.
Long ago, the Bortronians piled up Bortron 7 with trash, basically destroying their planet. Since there appear to be only three species of Bortronians, the Bortronians likely polluted their planet so bad that they drove all of the nonsapient species to extinction.
How did Sean get his head stuck in that vase in "Jet's Time Machine"? His head is bigger than the vase. It at least made sense with Carrot, since Bortronians are super stretchy, but Sean's not a Bortronian.
In "Back to Bortron 7", Carrot and Celery's boss is the same species as Sunspot, meaning that alien animals are equal among the humanoid Bortronians. Then why is Sunspot a pet? Is this Furry Confusion (think Goofy and Pluto) or serious Unfortunate Implications?
It's possible that there was an off-screen conversation where Sunspot was called a pet and the Propulsions assumed "pet" just means "family member of a different species", with this not being cleared up on-screen because it's not plot relevant.
, green eyes can sometimes appear gray or blue depending on mood and the weather.
Unfortunate Implications?