|
I never thought about it in the book very hard because gently caress yeah lets ram the chaos hell station into the sun with a rocket powered church.
|
#
?
Feb 21, 2017 06:32
|
|
|
|
| # ? May 8, 2024 08:17 |
|
|
Smiling Jack posted:Minimum required to fall into the sun. Well the orbital velocity is 24kps. Gotta cancel almost all of that. So rough figure: how much kinetic energy does Eros have in the first place? Roughly 6E8 megatons, or (Platystemon pointed this out I think), multiple times that of the Chicxulub impactor. No way Eros stays even remotely in one piece. If you want to accelerate Eros so that it gets to the sun fast enough to prevent anyone from landing and getting a sample, this number increases absurdly.
|
|
#
?
Feb 21, 2017 06:34
|
|
|
It’s more energy efficient to smash a large mass into Eros at “slow” speed rather than a large mass at high speed. If you smashed an Eros‐sized body into Eros and stopped them both dead in their tracks, your counter‐Eros would have a kinetic energy of only two million exajoules (we’ve run out of SI prefixes), which is only, like, all the solar energy that strikes Earth in four months. If you want megatons of TNT equivalent: five hundred million megatons. e: If you really wanted to play billiards with Eros, you’d start at the bottom of this list of retrograde asteroids. You’d try to find one that you could put on a collision course with Eros without too much work. It’s a short list, and even if you have a viable candidate, no retrograde asteroid is as large as Eros, so you’d need to add a lot of speed. Still, it’s better than using the Nauvoo directly. It’s free mass that’s already going pretty fast in mostly the right direction. Platystemon fucked around with this message at 07:03 on Feb 21, 2017 |
|
#
?
Feb 21, 2017 06:38
|
|
|
Maybe Eros isn't in its current orbit in the expanse, maybe they already moved it somewhere and that somewhere is a bit easier to smash into the moon?
|
|
#
?
Feb 21, 2017 07:17
|
|
|
If you can move Eros to a significantly different orbit than building a ship like the Nauvoo would not be anywhere near as big a deal as the show makes it seem. It'd be trivial by comparison.
|
|
#
?
Feb 21, 2017 07:23
|
|
|
Phanatic posted:If you can move Eros to a significantly different orbit than building a ship like the Nauvoo would not be anywhere near as big a deal as the show makes it seem. It'd be trivial by comparison. I don't know the math well enough to have an intuitive grasp, but if you put a giant magic Epstein rocket on Eros for, say, a few decades, surely you could do something with it? They've mentioned that the most ridiculous thing humanity has yet done in space is spinning up Ceres to provide about -0.3 g on the surface (and that Tycho did that, as well as spinning up other asteroids), has anyone ever figured the energy for that out, and how it might compare to this scale of thing? Edit: Phi230 posted:Guys. Eiba fucked around with this message at 07:35 on Feb 21, 2017 |
|
#
?
Feb 21, 2017 07:30
|
|
|
Tycho made their name spinning up Ceres, and it took a generation. That takes fuckall effort, compared to putting Eros on a collision course with the Sun.
|
|
#
?
Feb 21, 2017 07:31
|
|
|
I thoroughly enjoy the space nerd physics talk this show promotes. That's why The Expanse is the best. 
|
|
#
?
Feb 21, 2017 07:46
|
|
|
Eros is drat big peanut. It would take a hilarious amount of energy just to slow it, and all that would do is alter it's orbit a little bit. As it is a live (moving) load you are talking about an n (2?) body problem, so you have to stop the spin first, then stop the delta-v relative to the sun and it still wouldn't have had much effect. They mentioned that spinning up Eros was a milestone for humanity in the belt and only topped by spinning Ceres up. It was a stupid idea that would never have worked. Stupid plans dont work in the world of the Expanse. I think this is a thematic failure rather than it could never have worked anyway. They didn't "do the math" at all. They did the dramatics well enough though.
|
|
#
?
Feb 21, 2017 07:50
|
|
|
it's true. not many shows out there that could provoke this kind of discussion.
|
|
#
?
Feb 21, 2017 07:50
|
|
|
Collateral posted:They mentioned that spinning up Eros was a milestone for humanity in the belt and only topped by spinning Ceres up. It was a stupid idea that would never have worked. You’re right. I now recall that as the gang scrambles through Eros’ maintenance tunnels, they talk about how small they are. They were built to the height of an Earther because all the labourers grew up on Earth. Eros was the first generation.
|
|
#
?
Feb 21, 2017 07:58
|
|
|
AirborneNinja posted:I never thought about it in the book very hard because gently caress yeah lets ram the chaos hell station into the sun with a rocket powered church. This is my science.
|
|
#
?
Feb 21, 2017 08:33
|
|
|
AirborneNinja posted:I never thought about it in the book very hard because gently caress yeah lets ram the chaos hell station into the sun with a rocket powered church. The Expanse, Season 2: Ram the chaos Hell station into the Sun with a rocket powered church
|
|
#
?
Feb 21, 2017 12:01
|
|
|
In the grim darkness of the future, there is only perfectly accurate Newtonian physics. (Edit: I joke, but the discussion about dropping Eros in the sun is interesting) Kassad fucked around with this message at 13:59 on Feb 21, 2017 |
|
#
?
Feb 21, 2017 13:56
|
|
|
Now I don't know if this was discussed but don't you really need to only put Eros into a decaying orbit rather than dropping its angular velocity to 0? Isn't that a much smaller delta V investment? Obviously from a narrative perspective that would have given Earth and the MCRN plenty of time to land on the asteroid and get protomoleculed so it wouldn't have worked regardless but... isn't it correct?
|
|
#
?
Feb 21, 2017 14:09
|
|
|
With God's ship all things are possible.
|
|
#
?
Feb 21, 2017 14:46
|
|
|
OB_Juan posted:Promo for next week's episode looks nuts. This has officially become my favorite show. https://www.youtube.com/watch?v=Z0C-lSj2VPU (I guess spoilers for the next episode? Not sure on the rules there.) Wicaeed posted:The Expanse, Season 2: Ram the chaos Hell station into the Sun with a rocket powered church
|
|
#
?
Feb 21, 2017 14:48
|
|
|
I am however disappointed in how the show handles the protomolecule, and subsequently the Eros infection/broadcasts and protogen station. 1. The station was supposed to be more hard fought at least. I was hoping to see the fighting on the ring as described, where dudes were firing from elevated positions since the whole station was literally an uphill battle 1a. Dresden was supposed to be some suit who thinks himself above the OPA people taking the station. He's apathetic and dismissive, smug and superior. Not really in the show. 2. The protomolecule stuff was supposed to be more like fleshy and organic. Like some real horror poo poo. Vomit zombies. Moving torsos. Spines and bones like rafters. Columns of flesh with fused bodies. I understand it's TV. Wish it was on HBO. 2a. The broadcasts! It's supposed to be moans and screams and eventually insane murmurs, voices, repeating words and phrases, whispers. I was really looking forward to "DON'T YOU loving TOUCH ME" but they changed it to just a screech when the Nauvoo was about to impact. Phi230 fucked around with this message at 15:26 on Feb 21, 2017 |
|
#
?
Feb 21, 2017 15:24
|
|
|
emanresu tnuocca posted:Now I don't know if this was discussed but don't you really need to only put Eros into a decaying orbit rather than dropping its angular velocity to 0? Isn't that a much smaller delta V investment? You can only have a decaying orbit if there is an external force acting on the orbiting body. In the end, the delta v required is the same, the question is how fast that delta v is applied to the body.
|
|
#
?
Feb 21, 2017 15:26
|
|
|
Orbits decay through the emission of gravitational waves tho that's probably outside a reasonable time frame for a novel or tv show.
|
|
#
?
Feb 21, 2017 15:30
|
|
emanresu tnuocca posted:Now I don't know if this was discussed but don't you really need to only put Eros into a decaying orbit rather than dropping its angular velocity to 0? Isn't that a much smaller delta V investment? Orbital decay is caused by interaction with atmosphere. Eros isn't orbiting anything with an atmosphere that would decay the orbit. Other forces that cause orbital decay are too weak to be effective within a realistic timeframe.
|
|
|
#
?
Feb 21, 2017 15:30
|
|
|
That is to say, it would not work like a satellite that orbits the earth. Earth orbiting satellites are still within the atmosphere of the Earth itself, which extends out a very very long way. So those satellites still need some impulse to keep them in orbit or their velocity will degrade, which means they start to fall back to earth. Eros is orbiting the sun by means of the gravity curve around the sun, as it is very small so far out then the period is so very much slower, that is that the rock is very slowly falling towards the sun, but because of the curve of space it never gets any closer.
|
|
#
?
Feb 21, 2017 16:29
|
|
|
I thought orbits tended to decay naturally but I guess that doesn't make much sense. Alright.
|
|
#
?
Feb 21, 2017 16:37
|
|
|
Platystemon posted:Tycho made their name spinning up Ceres, and it took a generation. Do they ever mention specifically Ceres's spin rate? I figured it at about .05 rpm. Thing currently spins about once every 9 hours. So unless I screwed up the moment of inertia, it currently has about 1.6E15 GJ of rotational kinetic energy. That's six orders of magnitude less energy that you'd need to dump into it to spin it to .05 rpm (2E21 GJ) That's like an hour and a half of the total energy output of the sun. That's actually waaaaaay more energy than you need to totally cancel out Eros's orbital kinetic energy (2.5E15 GJ). No wonder it took them so long. Either I screwed up the moment of inertia, am greatly overestimating how fast they got Ceres spinning, or this stuff starts to fall apart if you look at it too closely. Still a great show, though.
|
|
#
?
Feb 21, 2017 16:50
|
|
|
Phanatic posted:Do they ever mention specifically Ceres's spin rate? I figured it at about .05 rpm.
|
|
#
?
Feb 21, 2017 17:03
|
|
|
emanresu tnuocca posted:I thought orbits tended to decay naturally but I guess that doesn't make much sense. Alright. They do Over billions of years
|
|
#
?
Feb 21, 2017 17:04
|
|
|
Phi230 posted:I am however disappointed in how the show handles the protomolecule, and subsequently the Eros infection/broadcasts and protogen station. I'm largely with you. In the books, the attack on Thoth Station is described as being uncharacteristically easy, but it was still a battle. The OPA didn't lose many people because Protogen security was outfitted with nonlethal weapons, but security did stand its ground—and agitated scientists were coming at the attackers with knives and poo poo. The nearly abandoned Thoth in the show was a letdown. Book-Dresden was better, too. The portrayal of the protomolecule's effects was definitely toned down for TV, and I wish they'd kept the audio feed more like the book's version, but I am kinda glad they largely dropped the zombie angle. The term "vomit zombie" got old quick for me. Phanatic posted:Do they ever mention specifically Ceres's spin rate? I figured it at about .05 rpm. I don't recall them ever discussing station spin in terms other than the apparent gravity that results, which is around 1/3 g on Ceres and most other stations. This spin gravity calculator is giving me about .025 rpm.
|
|
#
?
Feb 21, 2017 17:12
|
|
|
IIRC one reason they've dropped the zombie theme was that TV was already saturated as gently caress with zombie shows.
|
|
#
?
Feb 21, 2017 17:18
|
|
|
Combat Pretzel posted:IIRC one reason they've dropped the zombie theme was that TV was already saturated as gently caress with zombie shows. That's one place where I think you can really see that this grew out of an RPG campaign. One session of zombies is fine, but you don't built an entire campaign around zombies. But with a TV show, if people see a heavy zombie focus in one episode that's where they think the whole show is going to go. So yeah, fine with fewer zombies. emanresu tnuocca posted:I thought orbits tended to decay naturally but I guess that doesn't make much sense. Alright. Orbits don't just spontaneously decay, they decay because something interacts with the orbiting body. Stuff that's in low earth orbit will stay up there for only a few years or decades because there's still atmosphere up there; the satellites are constantly colliding with air molecules and slowing down infinitesimally with each collision. The ISS has to be reboosted to a higher orbit periodically because its enormous solar panels result in a *lot* of atmospheric drag. If you take a look here you can see that it loses about a kilometer of altitude per month. But in most of space there's not a lot of stuff to run into. A satellite in LEO will last a few years or decades, but the life goes up as you get higher. At 800km, you're up to 100 years, because there's less air to run into. Way up in geosynch orbits, there's nothing to run into but occasional cosmic debris, orbits there effectively don't decay. You can also get decay through tidal interactions, but the timescales for that are enormous and will only result in a lowered orbit if the orbiting body is already closer to the parent than a synchronous orbit. If it's further away (like the Earth's moon is), then these tidal effects raise the orbit of the moon and slow the rotation of the planet. Basically if you set the solar system as it is on fast-forward, random gravitational perturbations would eject Eros from the solar system altogether or crash it into a planet long before its orbit significantly decayed. Phanatic fucked around with this message at 18:35 on Feb 21, 2017 |
|
#
?
Feb 21, 2017 17:23
|
|
|
Hijacking the Mormon ship to ram the evil station into the sun is also an extremely player party thing to do, and must've been a little disappointing when it just didn't work. Also, Chef Boyardeez Nuts posted:With God's ship all things are possible.
|
|
#
?
Feb 21, 2017 17:28
|
|
|
Pharmaskittle posted:Hijacking the Mormon ship to ram the evil station into the sun is also an extremely player party thing to do, and must've been a little disappointing when it just didn't work. I really would like to read the documents fron the original rpg that they played. It would make an excellent coffee table book once the book series is finished.
|
|
#
?
Feb 21, 2017 17:59
|
|
|
Eh, I'd be pretty okay with it not working if it meant that a space-rock had learned to dodge. At least we just found out the kind of campaign we're in!
|
|
#
?
Feb 21, 2017 18:02
|
|
|
Chef Boyardeez Nuts posted:With God's ship all things are possible. Excuse me! What does God need with a Starship?
|
|
#
?
Feb 21, 2017 18:14
|
|
|
VagueRant posted:For those curious: New nitpick: One of the points of having two keys to set off a weapon is to put them physically far enough apart that two people have to act to make it happen. EDIT: I love this show because I showed this promo to MY WIFE who basically has no appreciation for anything scifi or horror at all, and she just said, "I love this show." I will always love the Expanse because we can watch this together instead of me having to sit through sentimental tacky crap like THIS IS US. HERAK posted:I really would like to read the documents fron the original rpg that they played. It would make an excellent coffee table book once the book series is finished. 100x this. OK, Eros rolls a Dexerity Save, SUCCESS.
|
|
#
?
Feb 21, 2017 18:49
|
|
|
I can just see the DM now: "okay so you just rolled a natural 20 on your crazy plan to ram Eros. You know what? Eros moved." "What?" "EROS loving MOVED I GOT A WHOLE SCENARIO PLANNED OUT HERE AND YOU FUCKERS ARENT RUINING IT"
|
|
|
#
?
Feb 21, 2017 19:22
|
|
|
Smiling Jack posted:I can just see the DM now: "okay so you just rolled a natural 20 on your crazy plan to ram Eros. You know what? Eros moved." Basically this.
|
|
#
?
Feb 21, 2017 20:01
|
|
|
They never get lost in the technobabble which is very good, I'm curious to see what they'll say about Eros doing that little shuffle but at least it won't be Voyager-esque "the protomolecule created an inverse tachyon warp bubble we need to use the DEFLECTOR DISH to create an anti-proton beam to hey miller what are you doing with that nuclear bomb?" Also I smiled a little bit at the bombs they were setting on Eros. 3.5kt fission charges, that's the kind of low-yield nuke I could see asteroid miners using to crack rocks open.
|
|
#
?
Feb 21, 2017 20:27
|
|
|
They never explain how the PM can do what it does, which is a good thing.
|
|
#
?
Feb 21, 2017 20:52
|
|
|
Yo you can spoiler poo poo like that you know.
|
|
#
?
Feb 21, 2017 21:30
|
|
|
|
| # ? May 8, 2024 08:17 |
|
|
NmareBfly posted:Yo you can spoiler poo poo like that you know. Yes, for gently caress's sake STOP BEING DUMBASSES ABOUT SPOILERS. Goddamn.
|
|
#
?
Feb 21, 2017 22:31
|
|