The ships in the show and books can reach insane speed. But in reality if they hit something at those speed, the ship would be destroid they even shot railguns in space. The 1000s of bullets would be floating around the sun all over the system, aswell as destroyed ships, ice, etc...
What happens if a ship colides with a bit of dust or debree?
Background Post: Absolutely No Spoilers In Post or CommentsFrom one of the authors in a previous post :
Double hulls, anti-spalling interiors, and a tacit understanding that everything you know and love could die at any moment for no reason.
And it should be noted that they've done the math, and space is so absurdly empty that you're very very very unlikely to ever hit an old PDC round.
But of course the chance is still non-zero.
Yeah, it’d really be a shame to run right into a whole stream of them. Really bad luck that
Honestly, it’s almost physically impossible to run into more than one of them unless they’re aimed at you.
Given the spread firing we’ve seen in the show, after only a couple kilometers of travel each round is already going to be dozens of feet away from the next closest one
Was referencing a particular scene in the Inaros saga. Won’t say which for spoilers
I’m guessing you missed the sarcastic tone of tajetaje. They are likely referring to something which happens in the books and the show but, spoilers.
They could just dodge to the left
And then jump to the right?
Put their .... hands on their ship?
And bring those PDCs in tiiiiiiiiiiiiiight!
When you dip we dip and blow up your ship?
Could you remind me? I've read all of the books.
I would, but this is a no spoiler post. Check Chapter 27 of Babylon’s Ashes.
What is spalling in this context? I don’t think they ever explain it. I figure it’s something about maintaining inner hull integrity but that was always just an assumption.
Essentially, you line the inside of the metal hull with cloth, netting, or lining, and it helps to contain fragments of metal the break off when the hull is impacted.
This is actually old technology as spalling was a big issue for WWI tank crews. Even rifle caliber rounds could cause spalling and injure crews.
That’s great added context, and cool to know what types of things could be useful for anti-spalling (like cloth or a lining). Thanks for the info, I really appreciate it!
That's still a problem in not so modern tanks (T-72 A's, Leopard 1s, etc). In fact, even non-penetrating shots can cause spall and concussion that can knock out the crew.
Spalling is the fragmentation caused by a projectile impact. If a rail gun round hit a ships hull, not only would the fired shell likely become tons of pieces of shrapnel, the ship’s hull would contribute to that shrapnel mess. Even if the shell doesn’t pierce the ship, the hull could give off shrapnel which is called spall.
That was a beautiful explanation my friend. Thank you for taking the time to answer so thoroughly.
Small price to pay for seeing other worlds
1/3 g = 3.26m/s2 (acceleration)
1 g = 9.8m/s2 (acceleration)
Earth gravity well escape velocity = 11.2km/s (flat speed)
Solar escape velocity = 41.2km/s (flat speed)
So a ship travelling for 8 hours at 1/3g, which is typical cruising speed, will be exceeding the solar escape velocity. Now consider that ships in combat scenarios are travelling at several g’s, and have likely been travelling at some fraction of g for days or maybe weeks, are going even faster, and then shoot a pdc which then travels even faster than the ship, will be stupidly fast compared to the solar escape velocity.
So pdc or rail rounds dont just hang around, they exit the solar system. Now keep in mind that at 1/3g it takes 120 hours to go from earth to mercury, and weeks for jupiter to earth, it really just shows how big space is, and therefore empty.
Now consider that when travelling almost everything is on the solar plane. It makes no sense to go above it by any meaningful amount, so more than half the shots made are not aligned with the solar plane and just go up/down and out.
So no, catching stray pdc rounds isnt really a big issue statistically or practically.
As for natural debris, its not a big concern space is so empty.
I always forget that tidbit about being on the solar plane. Isnt there a plot point or something involving something hiding above the solar plane?
Michio is really against the idea of being above or below the plane in book 6.
It’s like a desert out there. Barren of ships, stations, planets, asteroids(ice) and anything else to keep you alive.
In book 6, Pa's faction hides their resources out of the plane of the elliptic
Isn't the azure dragon also hiding out of the plane?
Yup, the Hungaria cluster, very start of book 6
Ecliptic
The question about hitting stray projectiles in space comes up here regularly. The math has been done many times and the chances of any stray ammo ever hitting anyone is impossibly tiny.
You essentially have to try to be hit by a stray round.
Look at how professionally they deal with the first time a railgun round takes off someone’s head (being vague for spoilers). Survivable collisions are trained for and no doubt practiced a lot given how little there is to do on a ship during those long arse journeys.
It wouldn't be a survivable collision at those speeds.
Right. The railgun round going a measurable fraction of c that took off dude's head was survivable for the ship but one PDC round that's been flinging around the system for a few decades creates a singularly and kills everyone.
This is actually a point I hadn’t considered. At what energy level (mass or velocity) does hitting a rock in a spaceship go from “it’ll frag your entire ship” to “it just punched a really fucking neat hole and continued on its merry way”?
With any luck, we'll live long enough to be around when they do the experiments!
My memory can't come up with anything other than a clean hole (perhaps with the spalling/shrapnel from metal removed at the contact point) that we see when a high velocity bullet hits a metal plate.
The books and the show indicate that PDC hits are pretty clean hits only damaging the bullet path plus the shrapnel. I'm reminded of two book scenes where a round misses Naomi's head by inches and another where rapidly cooling shrapnel is slowly bouncing around the cockpit.
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I absolutely love finding your kind of classic hostile nerd in the wild. "This guy said something I disagree with about the fiction we both like. I should probably insult him."
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The collision would not be survivable. Again, debris is not a solid railgun slug. That's the point. And dont play the fool. You showed no respect in your comment.
Edit: I won't delete this cause it would be wrong to erase the record.
I don't know why I was so mean to you. Must have woken up in a bad mood. Sorry for replying so harshly.
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*debris
The asteroid belt has one or two million rocks in it.
The gaps between those rocks are about a million kilometres.
You can fly through the asteroid belt with your eyes closed and not hit anything.
Imagine if there was a flat featureless desert with absolutely nothing in it except one boulder. And the desert was hundreds of times bigger than the entire USA. It would be real easy to drive across that desert without crashing into that rock.
Firing a couple million bullets in the asteroid belt is like adding a second rock to the desert.
You can fly through the asteroid belt with your eyes closed and not hit anything.
You can fly through the asteroid belt with your eyes wide open and never even see an asteroid
Its less likely than a stray cosmic particle travelling at Lightspeed for probably hundreds of years hitting an N64 at exactly the right time at exactly the right point to flip a bit that alters Marios Z co-ord mid speedrun and then propels said speedrun forwards by several minutes, making it an unbeatable world record.
Which is to say it's rare but has probably happened.
That didn't really happen though
Space is really really really big. The chance of hitting anything with the mass to cause damage is very small. Not zero of course but small.
That’s part of why the “turn and burn” is so important: you spend half your trip with a big fusion torch in front of you, atomizing junk. So the rare possibility of hitting something becomes more rare.
I never even considered that about the deceleration burn
Huh, they should have put something in the books about the second half of the journey being technically “safer”. Would have been an interesting bit of flavor.
Edit: "return" changed to "second half" of the journey.
It wouldn't be the return journey, rather the second half of each flight.
it depends orbital speeds are nothing to sniff at but the speeds reached in the expanse are insane. the dust would punch through the outer hull becoming plasma and sputter a metallic sheen on the inner hull. something sturdy and heat resistant like a pdc round would probably pnch straight through the ship whereas something dense and soft like a person would probably dump most of its kinetic energy into the ship and even potentially be caught by it,with each impact it and the impacted parts of the ship would become plasma till it leaves the ship or in loses enough energy they are turned into a fine pink mist and not plasma. may even get slow enough to splat.
Dust doesn't gain mass just because you collide with it at a higher speed. As long as the material is still softer than the hull, it's not likely to cause any damage.
As for bullets and debris, most of that is solved be the vastness of space and gravitational pulls. Anything drifting in space will eventually be pulled into a gravity well and given how much space there is, the possibility of it colliding with something gets slimmer the further out it travels. The only hazards we see with debris fields occur within close proximity to an explosion.
Even though a collision is unlikely in the first place, velocity is one of the terms in the equation that describes that collision. So while the mass doesn't increase, the total energy of the collision definitely does.
Anything drifting in space will eventually be pulled into a gravity well
No it generally won't. Anything moving through space unpowered will be on an orbital trajectory and unless something else interacts with it, like friction or another collision, it will just keep going. There is so little in space that those interactions are rare. That's why the planets still orbit the sun after all this time. PDCs will most likely exceed solar escape velocity though, so their course will lead out of the system.
I don't have the credentials to debate this. I'll just direct you to where i heard it and invite you forward your comppsints/corrections there.
Tiny pieces of paint fragments caused cracks in an ISS window and that's at relatively the low velocities of LEO
As for bullets and debris they won't drift until they fall into a gravity well, they are already in a gravity well. Rather the bullets would remain orbiting in the same orbit as the space craft just with a change in the vector provided by the Delta V of whatever the firing velocity is. I.E If the bullets were fired forward then they would have the same orbit + bullet firing delta V in pro-grade. Depending on which direction the bullet was fired the delta V would be applied in pro-grade, retrograde, normal, antinormal, radial in, radial out or anything in-between
What this all means is if you fired 1000 bullets in an engagement then there would now be a deadly cluster of bullets continuing to orbit practically indefinitely quite close to the original orbit of the space craft that fired them
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