Ceiling of Soup

In the book somewhere in the tunnel scenes (so I hear) rocky freaks out that grace returns later than he agreed because he slept in. That implies that rocky couldn't hear the ship from his part of the tunnel.

Compared with humans that can see for MILES unless something gets in the way.

They're absolutely chucking lampposts in all kinds of weird places to see if Grace can see them from the edge of his biodome at night.

Grace: "Oh yeah, I can see Adrian at lamp 58"

whoomp there it is!!! may i request grace and rocky hitting the "you know i had to do it to em" pose?

yknow i dont think ive ever been asked to draw anyone doing that pose before. thank you for giving me a brand new experience today

Fat Ryan Gosling this, Fat Ryan Gosling that

They see electricity, the same electricity of your brain. If something is not charged they can't see anything at all, and a room of non-conductive objects would be a complete sensory deprecation chamber. They can see a little bit, but they are nearly blind and only use it to notice sudden changes. If you flash a light at them they scream. Instead they just bring a device that generates a charge everywhere they go. They claim their whole planet is charged, but you have doubts

This apparently allows them to see secrets of the universe. They knew about the big bang through out their entire history, because they can apparently just see the beginning of the universe. They find it beautiful, but not all that interesting. You are jealous

Despite being in space, they have not yet discovered steel or had the industrial revolution. It's basically still alchemists and philosophers, but the alchemy and philosophy works and got them to space. You are no longer jealous

They rely on the temperature being way below 40 degrees Fahrenheit so all the fat stays solid and frozen, and die if it's warm. They consider you burning

They get all their energy from air, like eating, to the point they cannot hold their breath at all. They get other things from food, but refuse to prepare it aside from digestion. They just plop it in basically untouched

They age in dog years, dying a few months after turning 9, and only reach adulthood at age 4. That's an absurd amount of time to spend as a child. The one you met is apparently 5 and considers himself a mature adult. The tantrums say otherwise. Yes, he also has arcane knowledge naturally. You are more surprised they live this long considering everything else about them

They have 4 genders and assigned you one, maybe randomly. Kind of rude, apparently very complex, but they have no idea how to explain it. You aren't asking

I thought Grace would already be freaky with just the ability to perceive light alone but it would probably be way worse when it gets learnt that he has three additional senses over Rocky and all other Eridians for that matter.

Like,

Rocky: Constructing the biodome will be easy. The only thing we'll struggle on is sight since humans have 3 senses instead of 2.

Grace: 5.

Rocky: what?

Grace: we have 5 senses. debatably 6, though its unproven. sometimes people even think we have a 7th.

Rocky: It's like, a rock, but just worded cutely. Grace: How do you word a word "cutely," question? Rocky: Hmmm, well, it's supposed to be endearing. Kinda used to describe small things. Like something you'd call kid. I mean, uh, an Eridian child. Grace: Ah, understand. Name would be 🎶

When they get to Erid/A convo later down the line

Rocky: Aww, pebbles are so cute Grace. You didn't tell me they'd be so cute. Grace: New word, statement. Rocky: Oh, it's just the human word for a small rock. They're small, like a pebble and so, pebbles. Grace: Understood. Word for Eridian child is 🎶 sometimes called "Rocky." Rocky: ...Grace that's what you use for my name. Grace: Correct... Is Rocky okay, question? You are making face. Rocky: You've been calling me a child in Eridian this entire time?!? Grace: That is how Rocky describe name. Rocky also remind Grace of students... Grace ask again. Is Rocky okay, question?

Because while Eridians are incredibly strong and tough on the outside, on the inside they are actually quite fragile:

They have no immune system, so anything that makes it past their enclosed carapace and internal heating will pretty much kill them

They have no natural defenses to radiation of any kind

In general they have very little organic matter so anything that targets their cells directly is quickly lethal

They are partially cold-blooded and live at a very narrow temperature range (about 20 degrees C)

They rely almost entirely on one, highly developed sense and are helpless if deafened (can't even remember the layout of a room)

They are completely helpless while asleep and can't control when that happens

They will forcibly become dormant after eating AND when badly hurt enough (their equivalent of going into shock)

They require more energy to function than humans do, and have very little organic matter to burn in the case of starvation

In contrast, humans:

Have an aggressive immune system and internal mechanisms for dealing with cell damage

Have adrenaline which allows them to temporarily ignore injuries and perform abnormal feats of strength

Are persistence hunters built for economy of movement and capable of extreme levels of endurance

Exist in a very wide range of habitats and on a diverse diet

Are very hardy in general, able to survive massive injuries, lack of sleep, prolonged starvation, and intense environmental conditions if given proper care

The quintessential example of this dichotomy between strength and endurance is the Going Fishing incident in the book: Rocky is able to survive and move in G forces that are killing Grace and to physically wrestle off the chair crushing him, but he collapses from his injuries almost immediately after. Despite being injured himself Grace then carries his 400lb friend up a ladder, is badly burned returning him to his atmosphere, and then proceeds to get some basic medical care, hype himself up on pain meds and keep working (albeit rather badly, lol) while Rocky forcibly sleeps.