In the blue light of midnight

Earth, explaining to the Sun why they can't stay in their orbits: In other words, we’d all end up loony-balloony like Neptune.

Luna: *Glares.*

Earth, remembering Luna doesn't like when his name is associated with craziness: Oops, sorry.

Somewhere else:

Neptune: *Sneezes.*

The early episodes of Solarballs reminded me of a short series I watched as a kid and that's what got me interested on it, so I wanted to recommend it.

The series is called "Raindrop, Water is adventure". It was an educative children show about a sentient water drop (and cloud and ice cube) that taught stuff about the water cycle and the effect is has on everything (and we have on it). I think it was aimed to a younger audience, but I haven't watched it in so long I'm not sure.

Human: If life gives you lemons...

Neptune is probably the one that understands how Mars and Venus feel about Theia-Proto and Earth-Luna the best.

Why? Triton.

The same thing that made him lose his original moons he already cared for, gave him his current moons he adores. And it was his gravity that caused it.

That would have made him feel the same kind of guilt as the rocky duo: It hurt, but wishing it never happened would be like wishing they didn't have some of the most important people they have now.

There are nuances, like how Neptune didn't use his gravity on Triton intentionally, his original moons weren't sentient yet and Triton would still exist if they didn't cross paths, he just wouldn't be Neptune's moon, but you get what I'm getting at.

Earth, shortly after the Planet Revolution: I’ve got the best moon in the whole Solar System.

Luna, with a knowing smile: Because the others are gone?

In body type, I feel like pre-ejection he leaned into tall but thin, like when teenagers go through a growth spurt. Then, while he was banished, he lost a lot of weight because he didn't take care of himself. Once he went back, he started to put on some healthy weight but kept being rather thin.

He has scars from the ejection, but the one that looks like an X is more of a mark. It was a reminder of why he couldn't forgive Jupiter and Saturn since "X" is something unknown in algebra, a place where something is (maybe hidden) in maps and a symbol of something rejected or eliminated. In other words, because they gave those meanings to his name or because they made him X if it wasn't his name.

He has owl wings; however, they look like they are made of dark mist with little ice crystals floating on it. This is because to me he's Nox, so his wings are the darkness of the night and the stars in it. Maybe they look more solid or misty depending on emotions?

His hair too resembles a veil of dark mist, so is rather straight and long, but light.

Maybe bull-like horns, because of the Moon being very related to the night. And then he loses them/they break during the ejection because of that being the reason he doesn't have moons?

Another option is his design being based on bats/vampire. You know, fangs and bat wings, maybe also misty, that dub as cloak/cape.

He looked disheveled during his banishment, too obsessed with not missing a single detail he could use for his revenge to care for his looks (it's not like anyone would see him anyway).

Spoilers from the last Solarballs episode!

At first, I thought the show was following the 2 moon theory (2 moons formed, but the smaller got splattered on the bigger's far-side, creating the lunar highgrounds), but then only Luna formed when they showed us the aftermath of the collision.

The way their switch works makes it feel even more like that was the case, rather than them being a DID system (aka, Dark being an alter of Luna, who would be the host).

I'm guessing they just didn't think about it that hard back then when DSOTM was introduced, but I'd still like an in-verse explanation.

Planet X: My name is X.

Neptune: No, it's a letter, silly~

Or alternatively:

Planet X: I'm Planet X.

Have you noticed how everyone seems to have forgotten Earth is the biggest and most massive rocky planet and densest planet of the Solar System?

I wonder if it bothered him when that was eclipsed by being "the planet with life" and his friends started treating him as if he was delicate.

He isn't, we are.

Sun

Sun is built like a powerlifter.

His hair gets tangled during his high activity cycles and it slowly fixes itself as he moves past it.

Maybe has 8 arms, one for each major planet.

He looks like he's on fire.

Mercury

Mercury has athlete (runner) body and freckles.

Looks younger than he is for some reason.

Wings on feet and head, but they are small even if they move a lot, reacting to his emotions.

Very short hair.

Freckles, aka craters.

Venus

Venus doesn't have marked muscles, but they are firm to the touch.

What he does have is long lashes, which contrast a lot with his sharp features.

Long voluminous hair (reminiscent of his atmosphere), which he keeps because Theia liked it. Maybe he cut it after the Lost Earth arc.

Maybe afro-textured hair because of Aphrodite?

He looks the most like the Sun and he doesn't like it, especially lately.

Earth & Luna

They are both average in body type, but Luna leans towards thin and Earth towards thick.

Earth looks A LOT like Proto but his features are softer.

His hair stays however he styles it no matter the hair texture he gives it (aka, stright, curly, weavy...). I feel like it'd be layered, though.

Luna has Theia's eyes and a very round face (also from her).

Luna has a short bob cut (makes his face look even more round).

Since life developed on Earth, they took traits of the predominant species (aka, in the dino era, Earth had dino tail, now he looks completely human.)

Mars & his moons

Mars is a bit the opposite of Venus in body type, he's slighly toned, but soft to the touch.

His hair is short, thin and looks dry (like his atmosphere).

Valles Marineris is a scar across his chest and he also has a dip on his forehead from the Borealis impact.

Phobos and Deimos look a lot like each other but not that much like Mars, which is where the "They are captured asteroids" comes from.

Their hair is very unruly, no matter how much Mars tries to fix it, it doesn't last.

Earth, noticing carcinization: Why is everyone turning into crabs?

Humans: *Make Luna the ruler of the crab zodiac.*

I came across an article that said Nereid is an original minor moon of Neptune and the inner moons are debris of the original moons.

I wonder how Neptune would react to finding out.

He didn't lost all of them! Nereid just got in a weird orbit but survived intact! And Proteus and the others are part of those initial 3, so he still has them in a way!

Mars: Luna seems good, but he helps Earth cheat at cards.

Jupiter is built like a powerlifter (weight class is up to interpretation, but the heavier the weight the bulkier they are and I don't think he's a light weight).

Jupiter is built like Maui (from Moana), who is based of a wrestler.

The shape of his eyes is like an eagle's.

The shape of his eyes is like a cuckoo bird's and he also has their long tail and pointed wings coming from his lower back, which makes him look like he's wearing some sort of cape or cutaway coat (I'm not sure if that's the English word for "chaqué").

His hair is always fuzzy because of how powerful his electromagnetic field is.

The whole orbit has greek curls (Google says they are called ringlets?).

The Great Red Spot is just a prominent and differently colored lock of hair.

The Great Red Spot is a wound/scar that's still healing.

Sometimes, little electric sparks betray his emotions when they are intense enough.

Sometimes, his hair sparks with lightning as if it was a giant stormcloud.

They all have somewhat animalistic traits related to their myths. For example, Calisto has bear traits, Europa bull traits, Io cow traits and Ganymede eagle traits. The one's that were transformed in the myth have more prominent traits.

Ganymede looks like a young, rocky Jupiter. I'm mainly talking about his face, but the hair and body type may be similar too.

Callisto looks like a female Jupiter, but her usual expression makes it harder to see than with Ganymede.

Io's sulfuric acid clouds lit up with lightning when he's close enough to Jupiter, so he likes to blow them on his rings to make them more visible and cool (or around him to make his version of fireworks).