Codraroll

Funnily enough, I can't think of any straightforward examples that follow the entire recipe, but tell me you haven't heard this story before: Our hero, a retired military officer, is visited at his farm by his former superior ten years after he quit the military. The superior tells him that the Research Facility has found something they want him to have a look at. During an operation in (insert current war), a sudden incident happened out of nowhere and a whole platoon went missing. The last transmission heard from the platoon was a strange blip on the radar/noise/signal cut-out/sensor reading similar to what was observed in the classified incident back in (insert war that happened a decade or two earlier) where our pilot hero lost many of his men and which caused him to retire. Cue our hero saying "they're back" for the trailer. Our hero is taken to the Air Force/Space Force/Army Force/Underground Force/Navy Force base, stopping for a moment to admire a museum piece of an aircraft/spacecraft/car/boat/drill tank from his days in service on display outside the building. He's then taken straight into a briefing with a live link to soldiers in the field, going to see what happened to the platoon that went missing in the previous incident. He observes the scene for three seconds and asks one question, whereupon he scolds the general and scientists for making rookie mistakes, asking them at once to pull out the soldiers. Just as he does so, The Incident happens again and the link to the soldiers is lost. Our hero is given command of a team of special ops soldiers, and asked to investigate The Incident further. There's a scene in a big hangar-like laboratory where all sorts of generic science/manufacturing/equipment testing is performed at scattered tables out in the open. Here, the team is kitted out with the best and most advanced equipment government money can buy. As our hero gears up, he manages to break the fragile equipment by poking it with a finger, but easily wins a training exercise by relying on his instincts instead of the equipment. The scientists are all upset that he didn't use the equipment the way he was supposed to. Cue a quip about the equipment not being designed the way it was supposed to. The little platoon is sent out to encounter The Incident, in the best and newest aircraft/spacecraft/car/boat/drill tank available. Something mysterious happens that disables all the equipment and renders it useless, and after a thrilling action scene, our hero and a few of the soldiers barely escape with their lives. When they manage it back to base, they hear that The Incident is spreading, and the scientists have no idea what is happening. Fortunately, our hero has made an observation nobody else has, and he knows how to counter The Incident. The scientists are eager to equip him with the newest and best tech. Our hero refuses. The scientists insist, saying that "this is the best and most advanced piece of technology ever assembled." Cue something breaking spectacularly in the background, proving our hero right. Instead, the museum piece from the display outside the building is brought up on the runway, filled with fuel and obsolete ammunition, and our hero takes it to The Incident. The old equipment is immune to whatever disables the modern equipment. Our hero wins the day and saves the world. Anyway, while the story might be too clichéd to ever have been written in full, the sentiments linger in Hollywood screenwriting: Don't rely on anything modern, because it will always be useless. Trust your own experience instead of that of professionals - they are always wrong. The equipment used Back In Your Day is superior to anything that has been made since. Old technology will save us. The very newest generation of tech is likely to be outright evil. People in lab coats know nothing. Expertise is useless unless it comes from a guy without a formal education. One lone scientist may be right, but the entire scientific community is generally wrong. And of course, love conquers all. If the story is sci-fi, always expect the heroes to represent the old ways, the famers, the everyman, while the technologically advanced society is evil. The Empire furnishes their extravagant headquarters in polished metal and sleek iPod lines where not a speck of dust is visible. The resistance base is dirty, untidy, and full of outdated tech hobbled together with tape and wire. Small woodland creatures with sticks and stones will eventually defeat the tanks and lasers of the Empire. Sleek and modern = evil and decadent, old and used = salt of the Earth (at least up to a certain point - if the grime and wear extends to poor lightning as well as poor cleaning, it crosses over into being the lair of a serial killer). Star Wars is the prime example here, but you can see it in The Hunger Games or Pacific Rim too. The Jurassic Park series is basically all about how teeth and claws are better than guns and how science brings nothing but hubris. Same goes for the recent Planet of the Apes trilogy. I believe Battleship made a similar point about old vs. new technology, although I didn't watch it. In Armageddon, a bunch of oil drillers outsmart all of NASA for an operation in space. In Independence Day, a TV repair man creates a computer virus that destroys the alien mothership while the scientists at Area 51 are killed by the very thing they are supposed to have been studying for years. I'm a little annoyed with this "science is useless and technology is evil" narrative, to say the least.

The more I think about it, the worse of an idea the 1g 10 ft diameter cylinder becomes. How would two people standing upright pass each other if one was going from one end of the ship to the other? One of them would have to walk up the wall relative to the other and crouch down, as there would only be five feet from the floor to the centerline at any point. Stepping out of the way while standing up is not possible, as everybody's torso would always be in the center of the tube. This, of course, ignores how incredibly uncomfortable it would be to walk around with your head experiencing constant negative Gs and the dizziness of the Coriolis force. This calculator cites some sources that say 10 RPM is more than even seasoned pilots can adapt to within a reasonable time frame, and your ship is doing 24.4 RPM. But that assumes walking up the wall is even possible. You can't dedicate the entire spacecraft interior to be a floor. Presumably, all sorts of instruments, controls, screens, etc. would line the walls of the tube (just see the ISS), so you can't just put your foot anywhere. By the way, due to the aforementioned issues with standing up, and a lack of space for anything that pokes into the tube, the only feasible position for working with any of these would be lying down next to them, which is not a comfortable position to hold for any length of time even if you're not spinning around once every 2.45 seconds. Then there's the storage compartments. For reasons mentioned above, they would have to be recessed in the floor. And since the spacecraft spins so quickly, the gravity at the bottom of these storage compartments would be quite a bit stronger than on their surface, so working inside them would be a royal pain. Half a meter down, you're at 1.3g already. Solar panels or radiators (30 people generate three kilowatts of power even at light activity, so you'll have quite a bit of waste heat to get rid of) sticking out five meters beyond that would experience 4.5g at their tips. It would make EVAs difficult, to say the least. And of course, space. Space for 30 people in a 10 ft wide tube, with provisions to last for half a year. Using the ISS as a very rough comparison, that one contains a pressurised volume of 900 m3 and has provisions for six crew for ... I can't find any sources on the fly, so let's say three months. Your ship has five times as many crew and they're up there for twice as long, but let's say they're all Commander Toughguys and live twice as cramped as the ISS crew does, cancelling out that last doubling. So a pressurized volume five times that of ISS, or around 4500 m3 would be required. Let's say 4000, because it makes calculations easier. Now, we've already assumed storage compartments to be half a meter deep, so let's say you have a pressurized radius of 2 meters. 4000 m3 / (pi * 2 m *2 m) gives a necessary tube length of (1000/pi) meters, or 318.3 meters. 1043 footsies if you want to stay Imperial. You can find contrived reasons for halving that number, and maybe halving it again, but your ship would still have proportions like a toothpick. This is just the crew and pressurized storage compartments, remember; presumably you've got a power plant and a propulsion system as well. The point I'm trying to make is, 10 ft is ludicrously small. Both for the size of the crew, the magnitude of gravity you're looking for, and for the technological advancement required to make it a reality in the first place. If you can outfit a ship for 30 people for six months, and mount a nuclear engine at its back, you can easily build it with a bigger diameter. Building it 4 meters wide and 300 meters long would be vastly more difficult than, say, 10 meters wide and 50 meters long (which gives the same volume). With the ship's floor once again being half a meter from the hull (at a radius of 4.5 meters), you can do 1G with a spin rate of 14 RPM, which is still a lot more than what is comfortable, but enough for a semi-realistic Commander Toughguy to overcome while his crew does not. And you can have upright workstations, and all the storage in zero G in the middle of the ship. Scaling up the radius makes everything more practical overall.

Depends. How much money is actually allocated?

[snip] And for the record: What kind of rocket are you thinking of here? 30 people in a ship with a diameter of only three meters? It would have to be a rather long tube, and the people would constantly walk into each other because the distance from head to floor is shorter than the distance from head to celing, or the distance from waist to wall, by a pretty considerable margin. How would you even duck out of somebody's way? Taking a step to the side wouldn't move your head away from the centerline of the ship. Heck, with a diameter that small, and rotary gravity, people's heads would constantly experience negative Gs because most people are more than 1.5 meters tall. So yeah, you're effectively stuffing a lot of people into a tiny corridor, and one would think the technology required for a spaceship to sustain 30 people on a long-term voyage to Mars would also produce rockets with slightly less cramped living quarters. Messy situation. If the woman was already pregnant when the ship launched, the fetuses probably wouldn't survive the launch itself. If she got herself pregnant during the voyage, there's effectively no good way for it to end. It's an ethics question first and foremost, not a science question. [snip]

In the later Expanse books, railgun projectiles are said to fly at "an appreciable fraction of the speed of light", and one of the experienced engineers in the series does a double take when she looks up just how fast they go, so I think your estimate is off by a couple orders of magnitude at least. It sounds like several hundred kilometers per second is more like it. Just how the engineering of that checks out, I don't know (for a start, the guns are said to be powered by heavy-duty batteries - then again, technology will presumably evolve quite a lot in the next few hundred years), but provided you get a projectile up to that speed, there's no way you can stop it again with something you can carry on a spaceship. Nuclear plant buildings are designed to survive aircraft hits using several metre thick walls of concrete, and plating the reactor with that would be completely out of the question. And with that amount of energy poured into a projectile, it would be incredibly wasteful for it to be a simple hole puncher. If it doesn't lose speed traveling through its target, it means it fails to impart much of its kinetic energy onto it. Ideally, you want it to slow all the way down to zero, so the target has to deal with all that kinetic energy. The first impact of the projectile would start a cascade of shrapnel which would also travel at several kilometers per second, taking with it anything in its path and starting new cascades when the shrapnel hits something else. Essentially, a ship hit by a railgun round would turn into a giant shotgun aimed at itself. A hit at that speed would wring the ship inside out. That's why I thought that scene in Persepolis Rising was a bit bull, when...

They are also very fast projectiles. Then again, railguns in The Expanse have always been a little inconsistent, at least in the books. They're not mentioned at all in the first book, then in the next couple of books it's suggested they fire rounds at around five thousand meters per second - which would only make them useful at extremely close ranges, as at a modest 1000 km range it would take more than three minutes for the round to arrive at the place the target used to be. In the later books it's been suggested they fire rounds at "an appreciable fraction of the speed of light", which would make the rounds annihilate pretty much any ship they hit if they had a mininum of splintering capability. Heck, air resistance alone should be enough for them to flash-fry the rooms the rounds passed through, and they'd create pretty nasty shock waves in the process too. But instead, railgun rounds in The Expanse seem designed to pass through the target with as little friction as possible, punching a small, clean hole through the entire ship and exiting on the other side almost without having slowed down at all. It seems like their primary purpose is exactly the type of behaviour you described - going cleanly through walls for narrative suspense. They provide the threat of a "hole puncher" that can make sudden holes appear in the ship, killing anything along the straight line between them, but sparing the guy who just happened to sit in the next chair over. If railguns had provided immediate destruction of the entire ship every time, those "dodged the bullet" moments couldn't happen.

There are very few cases where you want to rendezvous with something and the relative speed difference isn't in the high hundreds of meters per second initially, if not more. You would have to spend a lot of fuel if you want to slow down to the point where inflatable shielding would make any difference on the outcome of the impact anyway, and by then it would be a lot easier to just continue slowing down the final few m/s than to prepare for a low-speed collision. If you're going from a relative speed of 700 m/s to 10 m/s and an impact is impending, you might as well go all the way down to 0 m/s. If you wanted to save propellant you'd have to stop at 200 m/s or something, at which point whatever you're hitting is going fast enough to put a really bad dent in your spacecraft (or itself) regardless of how many balloons you put in the way. And I agree with kerbiloid above, there are stickied threads in this forum for simple questions. No need to create a new one every single day for each new question.

You really like making new threads, don't you?

Ad Astra. Most of it. The movie is pretentious, slow and boring, don't see it. Minor spoilers ahead. An antenna built to search for extraterrestrials(?!?) is built to reach way up into the upper atmosphere. Humanity has bases on both the Moon and Mars, with commercial flights routinely making trips to both. Why bother building such a large antenna on Earth, if that's the case? A tiny little space station near Neptune can apparently send "electromagnetic surges" that wreak havoc on Earth and "threaten the stability of the solar system". Antimatter is involved. How it's obtained, nobody knows. Why the Earth's magnetosphere doesn't redirect it, nobody knows. And apparently a guy on that station has been trying to turn the transmitter off for thirty years without succeeding. The entire center core of a rocket (think a full Saturn V stack with side boosters for getting to LEO) is sent to the Moon. Where a tiny, Orion-style capsule detaches from it and lands. Why bother with the giant translunar stage? Who is the best suited man to guard a VIP on a tour from Earth to Mars? An octogenarian, of course! The best way to travel from one lunar base to another is by Apollo-style lunar rover. Just beware of pirates. The way they are dealt with is hilariously pathetic, a combination of words you don't see often. Lunar gravity is only weak outdoors. If you are indoors, gravity will be exactly like on Earth. Who knew! For some reason, Brad Pitt needs to go to Mars to record a message being broadcast to Neptune. The words "why are we stopping?" are uttered on a flight between the Moon and Mars. Stopping in space, that's a good one. A few minutes later, the audience will also wonder what the hell the reason for that scene was. A research station was in distress. We never find out what happened to the station, but a baboon on board kills the captain of Brad Pitt's ship so that Brad Pitt can be the hero and land it safely when the second-in-command panics over having to do a landing on Mars. Martian gravity isn't weak at all. Too bad Mars is a bit of a hellhole. An anechoic chamber is used to record a message for Dad Pitt. Anechoic apart from the large glass window into an operator's booth, that is. Kinda defeats the purpose of the padded walls in the rest of the room. Said message is sent "by laser" from Mars to Neptune. Everybody is bummed out that they don't get a reply in 30 seconds. Neptune is 2.5 light-hours from Mars even under optimal planetary alignment. The way to hijack a space ship launching from Mars is to climb in via the flame trench (which is filled with water - full of leaves) as it launches. A funny background detail: some numbskull apparently put a high-voltage electrical cabinet in the flame trench too. A zero-G fight scene ensues inside the hijacked space ship. During launch. The three stooges on board mostly manage to kill themselves while Brad Pitt tries to reason with them. The firing of a gun is involved, and a canister full of toxic gas. Flying from Mars to Neptune will always send you past both Jupiter and Saturn. Talk about convenient planetary alignment! At least they skipped Uranus. Locating a space station parked in an orbit of Neptune is easy. Brad Pitt can do it manually, while government search probes have failed repeatedly. Apparently the rings of Neptune are only a couple hundred meters thick! Who knew! You can park your ship above the rings, see a station parked below the rings, and jump between them through the ring itself. It is filled with debris, tennis-ball-sized rocks every half meter in every direction, but that can be easily overcome by holding a metal plate in front of you as a shield while you jump. Won't the impact with the rocks slow you down, or throw you off course? Rather the opposite, in fact, you will hit the station at greater speed than you left your ship! Space stations are equipped with big, spinning radars now. You know, for searching in a flat plane. It is mounted right outside the crew hatch, close to the main hub node of the station. If you cry in zero G, a tear will stream down your face. One guy can maintain a space station for 30 years alone after all his crew mates have been killed. Makes you wonder why they bothered giving it a crew of 27 in the first place... You can surf the shock wave of a nuclear explosion in space, and use it as a method of propulsion to get back to Earth from Neptune. Never mind the hundred-meter thick debris field/Neptune's rings between the explosion and yourself. Bad movie. Bad, bad movie. Not for the science (mind you, Gravity is full of bull too and still great), but for its overly repetitive narration, complete lack of emotion, and slow pace. Don't see it.

For me, the ending was the stupidest part. Girl press buttons, dinosaurs run out of the house, everybody says "This is a world where dinosaurs roam free now". The implication is that they will totally establish themselves as major players in the ecosystem and eventually present an existential threat to humans... ...except that the whole first act of the very same movie shows these very same dinosaurs being rounded up and captured in their natural habitat by a bunch of ragtag mercenaries in around two days. Captured alive, mind you. ...except that there were maybe fifty dinosaurs in total. What do you call a species that has fifty individuals living in the wild? Critically endangered, practically extinct. And those weren't even all of the same species. There was ONE T-Rex, for instance. No species had anywhere near enough individuals to sustain a population for more than a few generations before in-breeding does them in. ...except that these dinos were moved from a tropical habitat to northern California. A completely new climate. None of the prey or edible plants they were used to from their island. Crucially, none of the dinosaurs had feathers, which means they have no way to insulate their bodies against the phenomenon called "winter". Or even "warm summer days that don't reach tropical temperatures". The movie's script tries to scream "Be scared, dinosaurs are taking over now!", while being completely deafened by the reality shown on screen: That the dinosaurs would be easily captured, starve or freeze to death, or eventually succumb to a belly-flop into an overly shallow gene pool. The volcano aside, the dinosaurs are clearly much more endangered at the end of the movie than they were at the beginning.

Pretty sure they will manage to land it. Making it stay intact after landing is the tricky bit.

I'll take your word for it, but in what way is it?

At that point, one almost wonders why they just don't produce a bunch of them (the parts and assembly can't be that expensive once all the design work is complete, right?) and just try to get them to space on other launch vehicles.

Modern rockets use onboard computers for anything from guidance to fuel injection to communication with the ground. Question is, how much computing power/hardware is required to do these tasks, and sent up on a launch? Say, in terms of the capabilities of a modern mid-range laptop (minus, I presume, sound or graphics cards and anything like that), are we talking one tenth the computing power of one, or the combined power of 20? Or in other words, how much gaming fun could you have if you hooked a graphics card and a monitor to a Falcon 9? Are we talking Pong or KSP?

Presumably because a missile full of fuel and oxidizer went off right next to it. If I've understood it correctly, the RTG would be mounted as a heating element in an autonomous launch container to be placed on the seafloor, sort of an underwater, unmanned missile silo. It would keep the missile nice and warm, as the cold of the ocean floor might cause its liquid fuel to clot over time. However, it seems like during a test of this launch container the missile accidentally exploded, breaking the RTG and killing a handful of technicians present on the site. An accidental dirty bomb.

I read this thread this morning, but didn't get a chance to respond before now. Anyway, I think the briefest way to sum it up would be: Draw a border around your ship and any operations you carry out around it. Unless something carrying momentum (that is, mass at a velocity) crosses this border, your ship won't accelerate. As six pages of discussion demonstrates, it can be said more elaborately than that, but this should be the very core of it.

This brings to mind Weir's second book, Artemis, where Kenya (of all places) gets a pretty big leg up in the space race by providing a launch facility on the Equator and basically telling private companies that the red tape doesn't apply there. Then again, I suppose that if you can afford to launch a vessel to space in the first place, you could probably afford the fine too.

Nah, it's just launched in a configuration where the side boosters, the fairings and the second stage are all deployed at the same time...

It's too big to be brought safely back to earth in one piece, it's too expensive to bring back all of it regardless of how many pieces it's cut into, and its utility as a museum piece would be limited anyway (even if you had the exhibition space, it's not like you could do tours in it). If somebody want a full-size ISS on display, building a sufficiently accurate replica would be cheaper by several orders of magnitude. I'd focus on bringing only parts of it back. The cupola is probably the most iconic part of ISS, that thing could be pried off and taken down using a suitable craft. Maybe a solar panel could be folded up and brought back as an exhibition piece too, and all sorts of little interior bits could also be brought down in regular cargo missions. The guitar used by Chris Hadfield in the Space Oddity music video, for instance. The rest of the station would be deorbited piecemeal if I understand the procedure correctly. Yes, most of it would be lost forever, but its life would be well documented, and NASA tends to be good with making replicates of all sorts of flight-ready hardware. Every strap of velcro up there should have a twin somewhere on the ground. If the original is too inconvenient to conserve, at least the twin is stored for posterity.

I wish and hope for some colonization/permanent base rework. It would be so cool to have the option to establish bases (and launch sites) on other bodies, it would be a great reward for interplanetary exploration too as well as making it less intimidating for inexperienced players. It's easier to get to Dres if you start out of Duna, for instance, but it would cost a whole lot more funds to launch even the simplest spacecraft from there, so there would be a tradeoff. Either way, surface bases need some rework. Docking anything on a planetary surface is hellishly complicated, and the bases you end up building look something like oversized LEMs. A more convenient way to assemble surface bases would be really cool.

Off-topic question, but why do you use the spoiler tags so much? I can understand using it to hide pictures or longer paragraphs of text so the post can be scrolled over faster upon repeat page viewings, but for single lines of text I really don't see the purpose.

If I understand correctly, driving a rover on Mars is basically like: "OK, we've spent the past week finishing the terrain survey from the rover's current position, and the third party control agrees it's safe to continue onwards. Today's business for the entire team is making sure the rover traverses the next fifteen centimeters of landscape as calmly and controlled as possible. Maybe we can go ten more centimeters next week if everything goes well." Okay, maybe not that slow, but still, the rovers aren't built for a pace faster than that of a walking plush toy whose batteries are about to run out. How would they handle helicopter operations on a body so much further away than Mars?

SpaceX continues to be so very Kerbal. That 90-degree flip and horizontal flight across the surface is something I've done a lot of times in that game. RUD at the end and all.

Speaking of, wouldn't it be a good idea to rename the thread accordingly? "Boeing CST-100 Starliner" would work as a thread title, alternately with "discussion thread" at the end. Which moderator would we have to tag to get it done?

From what we've seen of construction at the Cosmodromes, this part seems credible and likely to happen. This part does not.