Spacescifi

Good answer! Put of me is laughing as I am picturing you saying all if that in a British accent. Maybe you know this, maybe you don't, but accross the pond in the USA, there is an assumption, likely influenced from movies and TV, that smart or classy people have British accents. Because the ones on TV tend to. So when you admitted you don't know but will give it go it made me want chuckle. Also...saying give it a go is a phrase among others I know people in the UK use more often than folks where I am from. Virtually most all of my UK media knowledge of how they speak comes from watching Dr Who during the Ecclecton-Tennant era. EDIT: Hope I did not needlessly offend anyone. I actually like British culture, what bit of it I know, from the accents to the fish and chips. I just found it amusing since on TV among American characters, I can't remember the last time the British guy did not know something Probably that all just too much Dr Who though, since he and now she is the hero andTime Lord extraordinaire. Regarding the NTR, perhaps you and I accidentally solved the problem? Want greater heat into propellant? Narrow flow. Want more flow? Build a BIG REACTOR. I think the really hardest issue is thermal shock on the reactorbecause of cold propellant. So that is hopefully an engineering issue where mankind can engineer new materials that can take the thermal shock. One day.

Well...with advanced nuclear designs like LANTR and NSWR (I know NSWR is not safe) having multiple nozzles means multiple reactors does it not? Is not one big reactor and one big nozzle better than a bunch pf smaller ones or not? Extra complexity tends to invite Murphy's law right? Imagine if they were FUSION reactors LOL? Again...if I am in error...let me know. Thanks.

Assuming you had a legitimate SSTO using some advanced nuclear engine or super hot propellant you would also want less but huge main engine nozzles. Another reason is because you are not using a chemical reaction so chemical combustion does not matter. The last reason is thermal. Air conducts heat, so having one nozzle lose heat to the air on ascent is better than radiating heat off to each nozzle side by side. Point? If we ever do make SSTO's, main engine nozzles will be optimized to just be one big one. If I am wrong or in error feel free to correct me. Otherwise you may add what you know. Than you.

In that case portals would actually slow stuff down. Anything in orbit cannot send anything to. Earth without slowing it down Doubt they can do that on an orbitng ship already going that fast. So you really cannot afford to think about the why too much to enjoy the story.

Oh I get it. Just using a nozzle is more efficient for a portal system because shooting propellant orbital velocities to match portal speed is harder. You can still cool ship with onboard LH tanks and use radiators to slowly cool them down. It also means you probably cannot thrust indefinitely...even with portals. Unless you have one where the speed between portals is a lot closer and you are spraying propellant between portals in directly to your ship tanks. Real reason? It's cool for how I can use it for eliminating certain...stuff. Cool effects Heh heh....arbitrary plot man...don't think about it...don't think about it. I actually prefer clasdic portals where speedy thing goesin speedy thing goes out and that speed is ADDED on top of exit portal speed as opposed to having a speed budget have to reach before you can even go through an exit portal.

Nice. I like it then.

Are you saying that if I throw am item to a portal in LEO, it WON'T pass through UNLESS it is going at orbital velocity? If that is the case propellant depots will be massive to accelerate stuff. Make a water cannon that sprays at orbital velocity much? Neither do I LOL. High tech requires high tech!

Maybe...bit not of it is hilarious. I would make it so if I went that route. How many times do the lamest things win wars? Russian winter beat both Hitler and Napeleon. A litte over a hundred years between them. Same russian winter.

Got it, so a combo of forethought and real test result review is vital to see what worked and what did not. Compare notes as it were. DO let your right hand know what your left did...at least when it comes to evaluating unknown potential.

I see...so real flight testing is the ultimate proving ground for success or failure. Kind of like life. One can guess all day about what COULD happen or just do a real test and write out the test results for future reference. The scientific test method could be useful in life for all kinds of unknowns one may wish to try. Data derived from resl tests never lies. That you can bank on.

I see. I was beginning to think all the crashes were due to stuff he could have caught. But it seems he has a deadline so he is going ASAP so if crashes cannot be avoided and that is the price of fast learning so be it. Did not know comp testing was more tedious than actual spaceship flight tests LOL.

Um...why cannot Elon just run computer simulations of what could go wrong BEFORE it does? Might save some metal from becoming scrap? What? Some stuff you cannot predict? Cannot pressure and propellant flow be calculated for? That's what computers do best! No offense really, RUD's are entertaining, but watching Starship do what it was meant to do would be more so.

Remember the Oort cloud...and that every solar system may have one. Which can kill spaceships on the way in. Orion is doable but far from most optimal. Fun KSK post re-quoted: So what exactly did happen to the enemy flagship, Captain?" "Uh - we picked up a short duration, high intensity radiation source on the edge of the Oort cloud, Admiral. As far as we can tell, they hit a magnitude eleven object on the way in. Feel a bit sorry for the blighters to tell the truth." "At least it was quick." "Aye, sir."

Not zero radiation but less and far more localized. Like you should not have been that close anyway. Not like with a normal nuke and you live 25 miles away and STILL might get cancer from it LOL.

Here Is The Scenario: SSTO's are common because everyone of them is networked via a portal network that links them to propellant stations on industrialized worlds. Here is the catch: Portals tend to pulverize and or liquify solids that pass through. Not EVER used for passengers. For example if you throw an ice cube into a portal, it will become liquid on the other side. If you throw a rock or a piece of wood through it will blast into a cloud of debris. Liquid propellant is not effected and therefore is pumped through by shooting it across portals into a ready pipe on the other side. Main Question: Say you want to be able to burn propellant for an hour at 1g in interplanetary space? Obviously heavier ships get billed more heavily. What kind of price would a propellant station charge? Is 1k (thousand dollars/credits) per hour of 1g sound reasonable? Incidentally if you do something crazy they can also refuse to feed you any more propellant. Leaving you stuck with classic NASA scenarios and the tyranny of the rocket equation. Question 2: Would not some propellants be cheaper or pricier? Obviously doing higher accelerations for hours will be plenty costly too. What would be the dirt cheap propellant? Saltwater? Not even processed...but does require onboard ship machines to separate the LOX and LH out. Or a nuclear reactor to just use it straight as propellant. Mid-price propellant? Expensive propellant? Probably the toxic high thrust stuff like mercu-LOX (liquid mercury and liquid oxygen). Or just burning liquid fluorine with a nuclear reactor. Why is RP-1 propellant considered to be so good? Hilarious question, but what would RP-101 look like or be? Thanks.

For what it's worth, in scifi I am partial to using currrently not possible pure fusion bombs. Less adiation. No electromagnetic pulse. But IRL all we have is nukes sooo......

Hmmm...Elite dangerous much? And no...ED ships don't fly well in the air KSP. Let alone reach orbit on their own like SSTO's.

You know I like project Orion. I also like the Starship project (Elon's 'baby'). Now when you think of project Orion you usually think of it launching via a bunch of booster stages which it drops away and I presume also are obliterated when the orion begins blasting bombs out the back. Actually, you don't have to waste boosters at all. The ENTIRE orion can be designed to reach orbit on it's own with ZERO infrastructure. How? Imagine this: 1. On the launch pad the SSTO Orion is shaped like a massive cylinder. The bottom end has a cluster of rocket engines within the 'skirt' of the cylinder, much like Elon's Starship. The top of the ship has the pusher plate supported by pistons and shock absorbers. 2. Orion launches via rocket engines using the most thrustiest chemical propellant and rocket engines mankind can currently bring. You need it to launch high enough to not wipe out the launch pad/facility with the bomb air blast. 3. In starship fashion, after reaching the minimum altitude required not to wreck the launch area, the orion will flip over with powerful RCS thrusters so that the pusher plate faces the bottom and the rocket end faces the top. 4. For the crew to be comfortable the ENTIRE crew habitat area must be a sphere that can rotate, like a gyroscope. Rotating within the ship so that down will ALWAYS align with ship thrust and planet gravity when landed. This is only an engineering issue that is also solvable. 5. Then the bombs release and blast and the Orion goes it's merry way to wherever it wishes in the solar system that it has enough nuke delta v for. 6. To return to Earth the orion could either: A: Go to the moon and use leftover rocket propellant to land, flipping to present the rocket side and using landing legs to land. On the moon ideally a propellant depot with water available to pump into Orion would be great. Barring that the Orion would be forced to use onboard equipment/machinery to harvest moon ice and convert it to rocket propellant. B: You could hunt down asteroids or comets for the same reason, but it may or may not pay off with the propellant you want most (likely water to do LH/LOX). 7. Once you have filled up your propellant tanks to enough to where you KNOW you can land in 1g on earth, you set a course for earth. 8. If you did NOT fill your tanks up enough enter low Earth orbit and request orbital refuling tank/tanks launched into orbit. Use them to fill up sufficiently and then you can reeenter the atmosphere and land back near if not on the site you launched from. Hurrah! And now you can analyze this if you like. Pros: All the advantages of an SSTO combined with Project Orion. Self landing/launching. Perfect for exploration. Cons: Gyroscopic rotatable habitate for entire crew is more complex than standard crew module decks. Project Orion nukes for radiation in the air during launch. Ship must be sturdy enough to hold it's own weight whether it flies forward with rockets or flips to use the pusher plate. Good news: All are only engineering challenges. It's not like trying to build a fusion reactor and physics keeps telling you "I'm melting! Too much heat...can't hold out...much longer." What do you think? EDIT: I would love to see someone build this in KSP and show a video just to demonstrate viability. Any suggestions on who to ask? No I don't have KSP nor do intend to play it as I don't have the time as I have enough work on my plate. I do enjoy the vids of people's creations and. Scott Manley of course!

It is not ever never necessary on Earth unless one wants something bad enough. Yet with space travel this good, the cost of going exterminatus on a planet is a lot higher than just say...building space habs. The one place space war actually makes sense to me is attacks on space shipping and piracy. In other words, space trade wars. Motivated by a desire for profit and probably greed too. Solely between the ships among the stars. Planets pay for it. Ships bring it. If they can survive.

Yeah...laughing at real attempts to pass off scifi as reality is amusing when you know better. I do think that based off KSP knowledge alone, anyone can design a vehicle that can do the job required...maybe not as good as scifi, but it can get the job done. With enough staging, one can launch ANYTHING...not tied down.

You may be surprised that questions may have already been answered. People here know I have asked a few in my time. And yeah...these here KNOW what they are talking about. Can calculate anything you throw at them....for fun. Sometimes calcs are off but someone else will usually correct later.

I will level with all of you. Orbital dynamics and all the stuff regarding newtonian movement goes out the window when you can lightspeed around a solar system. All the knowledge..wonderful knowledge by the way...means NOTHING and cannot be used that has been gained. I cannot abide by that. Made me laugh about the cost comment. I agree fiction requires just that. I just prefer some fast FTL but normal intersystem travel times. Who said I was writing a war story? However...it is not a utopian scifi universe by any means. So the threat of being blown out of the sky is still real. Space war really is kind of nonsense. A very special kind requiring very specific circumstances. Generally speaking, planetary invasion is NOT fun for the conquerors. You either make a wasteland or the defeated create one via scorched earth policy like on Babylon 5. https://m.youtube.com/watch?v=MXkIuVLnsFE

1. Good realistic alternatives exist. Don't want your bones to turn to mush? Separate vessel with a kilometer long tether and rotate 1 RPM with thrusters for 1g gravity. Granted I know this IS an engineering issue and lots of rad shielding is a given. Yet for people in space to be a common thing then everything they operate will need to be man-rated anyway. 2. Semi-fast fast travel can be done via Project Orion. Just pull in the rotating tethers before you start blasting the bombs out the back. It really is good enough. 3. Really fast space travel is is plot breaking. I have no problem with instant FTL, but once there if you can zip around warping at lightspeed that has some dangerous implications. It would make any idea of space combat as we know it obsolete, and render ship to ship combat obsolete as well. So mucj for scifi...not everyday a trope kills another trope LOL. 4. Power required for 1g or any good thrust constant acceleration is massive. When in doubt, the lower power option *cough* Project Orion, is simply waiting for you and available to use.

Well as I have said for sometime...if you have FTL/warp/space translation/jump drives, you would think fusion they also have. As it SHOULD be easier of a feat. That said, common sense means average joes won't be toting rifles with fusion bullets. But SSTO belly lander orions with bomb pellet propellant utilizing pure fusion? Yeah..why not? I have no argument against them. Just means the launch station is in the desert. And landing is done with conventional rockets. It is possible to make a tall belly lander vessel SSTO with dual axis rockets for initial launch and landing, and an oblong pusher plate that is below sitting crossways while landed. During ascent rocket engines would cut off, the pusher plate would rotate to fit straight across the ship's belly (thereby protecting belly/rocket engines from blast) and release the bomb pellets and continue to ascend vertically VTOL style. No flipping required. The only flip required is once it reaches space, then it flips to face orbit so as to circularize and stabilize an orbit while impelling itself forward via pusher plate blast.

I see, so the lightesr element on the list...hydrogen, is the most likely one to be used. Least energy required in comparison with the rest...and coincidentally also the one stars use. So water and ice are like gold in space. Not too much has changed I see LOL.