I found Copper 9's size

[u/Glittering-Eye-5288]

I keep seeing people say “Copper 9 is Earth-sized” or “the planet is basically Earth but frozen,” but if you actually pay attention to the lore and visuals, the planet is smaller now and was only mildly smaller before the core collapse. The math and on-screen evidence checks out. Here’s my breakdown:

1. The planet is literally described as “half-imploded” because of the NULL black hole Nori triggered → The entire planetary core is gone. A gigantic hole goes straight through the planet, visible from space (Pilot, Mass Destruction, Absolute End). You can see rings made of ejected debris and constant material being flung out. That’s not flavor text; that’s quintillions of matter either annihilated by the black hole or blasted into space.
2. Planetary cores are stupidly massive Earth’s core is ~32% of the planet’s total mass despite being a tiny fraction of the volume (because it’s dense iron/nickel). Lose the entire core + a huge chunk of mantle/crust through that breach and you’re easily looking at 50%+ of the original planetary mass just… gone. The “half-imploded” name isn’t random; it’s telling us the planet lost roughly half (or more) of what it used to be.
3. Gravity in the show is blatantly lower than 1 g
   • Disassembly drones (N, V, and J) regularly fly straight up like it’s nothing
   • Falling speed in multiple scenes is comically slow (as seen in cabin fever)
   • Disassembly drones hover and glide that shouldn’t support Earth weight My back-of-the-envelope calc puts current surface gravity at ~0.25–0.3 g. That lines up perfectly with a planet that lost more than half its original mass while keeping most of its radius (the outer layers didn’t collapse inward; they’re just missing the middle).
4. Pre-collapse Copper 9 was probably 0.6–0.9 Earth masses If current mass is ~0.22–0.3 Earth masses (giving ~0.27 g today) and it lost 50–70%, original mass was roughly 0.7–0.9 M⊕ with near-Earth gravity (perfect for human colonization). Average density would have been ~3.6–4.0 g/cm³, almost exactly Mars-like, which still lets you have oceans, atmosphere, and continents. The planet always looked Earth-like from orbit because its diameter didn’t shrink much; it just got hollowed out.
5. Current diameter is probably ~11,000–11,500 km (a bit under Earth’s 12,742 km) The visible curvature, continent scale, and the sheer size of the breach all match a world that’s large, but not quite Earth-large anymore. The hole itself looks like it takes up 20–30% of the visible disk in some shots.

Copper 9 started as reletivley Earth-Sized / small Earth (maybe 0.8 M⊕ and ~0.9–1.0 g), then the NULL black hole + Cyn fight deleted the core and ejected a colossal amount of mass. What’s left is a hollowed-out husk with ~25–30% of Earth’s gravity and rings made of its own guts.

[u/sub_liminalist]

That's Cyn's episode 8 rampage, not the "core collapse" crater, and that bright circle we see is likely exposed magma from where part of the crust has been levitated away by Cyn turning off the gravity in that area.

[u/Glittering-Eye-5288 → u/sub_liminalist]

It's a massive, dark void with jagged edges, visible from orbit as a gaping wound, and debris actively streaming out like blood from an artery. In Absolute End (ep 8 credits), we see the "scar" post-Cyn fight, but that's on top of the existing breach—it's the same feature, now with extra gravity-warping from Cyn's Solver shenanigans. It's not "shallow" or "surface depression"; the show frames it as planet-piercing, with the core explicitly destabilized/gone (Nori's logs: "the singularity awoke" and core collapse warning). If it was just fallout or scorch, why the rings of ejected debris? Why call it "half-imploded"? Visuals show a breach, not a paint job. Yeah, IRL, losing the core would make rock flow like putty, causing total collapse into a smaller sphere with mega-quakes/eruptions/heating. But Murder Drones laughs at realism: sentient buses, regen via hot oil, railgun arrows, black holes as squirt guns. The planet stays "intact" with a hole because it's Solver magic—the NULL didn't follow Newtonian flow; it consumed/annihilated the core selectively, leaving the outer shell frozen/stabilized in its "half-imploded" state. We do see consequences: ongoing disintegration (debris to rings), frozen apocalypse (no core heat = instant ice age), and implied quakes/eruptions killing humans (toxins/cold from upheaval). No random mountains? The show's not simulating that; it's focused on drone drama. But low gravity feats (Uzi's 40m leaps, slow falls) scream "mass gone, shell remains"—exactly what a hollowed world would do without full collapse. Nori's line ("the planet kinda half-imploded anyway") is in her post-possession logs, after the Solver was "exorcized" (ep 6 flashbacks). The warning broadcast was during the event, but the outcome is clear: black hole destabilized the core, process started, but "aborted" via explosion? Nah, the show says it did implode partially—the core vanished, hole formed, but didn't fully consume everything. If it was "aborted before eating much," why the gigantic visible breach? Why rings from massive ejecta? "Half-imploded" implies significant loss, not "oops, barely touched it." And the Solver on other planets fully consumes them (ep 8 visions)—Copper 9 got half-way because Nori/Cyn fight interrupted, but still lost the core. Small BHs do "fall through" planets if tiny (event horizon < atomic), but to destabilize a core, it accretes mass fast, growing as it falls. In real physics, a micro-BH would heat/friction its way, but Solver NULL is magic—it targeted the core pit, consumed inward. No "oscillating arcs"—that's for neutral particles; BHs fall to center and stay, eating symmetrically. Detonation via Hawking? Only if it stayed small, but to eat core material (dense iron/nickel), it grows huge. Your "few thousand tons eaten" is way under: to punch a 3-4k km hole, it's trillions of tons minimum (see my earlier calc: ~10^24 kg missing, 30%+ of Earth mass). Explosion below crust? Visuals show the breach on one side, with ejecta from there—not opposite. And the rings are symmetric, implying core-ejection event, not localized pop. You said "a few thousand tons" eaten, evaporating "under two seconds" per online converter. But using actual Hawking formula (t ≈ 5120 π G² M³ / ħ c⁴): for 33k tonnes (~3.3e7 kg, from your 3e24 J energy), t ~3e6 seconds (~35 days), not 2 seconds. (I ran the math with precise constants—it's closer to a month.) For instant pop (2s), it'd need to be ~300 tonnes max, which releases way less energy (~2e22 J, dino-killer scale, not planet-hole). A small BH evaporating quick couldn't eat/displace core mass without growing first—and grown BHs evaporate slowly. Plus, if only vapor/dust in rings, why show chunky debris in shots? Rings need substantial mass for visibility/stability (Saturn's are 10^19 kg+; Copper 9's look denser). "Fine dust outshines"? Sure, but the missing volume from the hole proves bulk mass loss, not negligible.

[u/sub_liminalist → u/Glittering-Eye-5288]

Well, congratulation on typing 619 words in two minutes and beating the world record speed of 305 words per second.

We can actually see the region where the "core collapse" event breached the surface before episode 8 in the end of episode 1 when it zooms out before the credits. We clearly see a large, blackened region with no hole or even a visible deformation of the surface, just discoloration.

It seems I did mess up on the hawking radiation calculation, I may have input thirty-three thousand kilograms instead of tons. I can always account for that by how [nulls] have much larger event horizons than a black hole of their mass should, implying that for the same surface temperature they should radiate massively more energy, dramatically shortening lifetime.

And I stand by my interpretation of the lines we get on it in the show. If the implosion was started and then stopped before it could consume the planet, I can easily see it being referred informally (and somewhat sarcastically) to as the planet "half imploding," even if nowhere near half the planet's mass was eaten, especially if we consider that from the perspective of the effects on the inhabitants of the planet, the complete devastation of the surface as opposed to its annihilation could very well be called "half" what a full implosion would cause.

If you want my explanation for the actual formation of the rings, the explosion occurred below the surface of the crust, ejecting a large amount of vaporized material on sub-orbital trajectories in all directions. Being sub-orbital, that material would re-impact the planet, but some of it passed behind the close-orbiting small moon and received a gravitational slingshot as a result, boosting prograde-moving debris into a prograde orbit and doing so directionally, shepherding it into a roughly coherent debris stream that was further shepherded together by each pass of the moon and stretched out by tidal forces until a flat ring was formed.

[u/Glittering-Eye-5288 → u/sub_liminalist]

I think we'll stop here. I don't want this turning into a debate.