Spacescifi

So what if the electromagnet pusher plate was also an X-ray mirror? Would that no doubt increase impulse given for each bomblet? And could you not detonate the bomb closer to the plate then? I know some stand off distance is necessary, since a magnetic field will block plenty but not everything. But if the X-rays also get reflected back that should add up to overall impulse. More than if you took a plain Orion with a plain oiled pusher plate and detonated bombs out the back. Am I right? EDIT: Whether wecan make X-ray mirrors matters not, this is assuming we could.

We are familar with project Orion but I was thinking of giving it a slight upgrade. Since we know that nukes ablate the pusher plate, limiting the lifespan. Now they say you can spray the plate with oil between detonations to virtually eliminate ablation, but soonet or later you will run out of oil. What if you made the pusher plate a powerful electromagnet? Magnetizing it right before each detonation and demagnetizing it for each bomblet release? Would the magnetic field not help prevent ablation somewhat in the absence of oil spray? Since magnetic fields would deflect and repel the plasma from the detonation. With an uber enough magnet pusher plate, you could detonate the bomb only a few meters offand the magnetic field would still repel the plasma cloud. What do you think?

This is a paraboloid shape, which looks roughly like a shortened standard shape for bell nozzles. My understanding is that this shape is most efficient, as it pushes all exhaust backward in one direction, moving the rocket forward. Flashlight mirrors at times employ the same design to focus a light beam as it spreads out in one direction. The only reason rocket designers lengthen the nozzle has much to do with accelerating the exhaust as much as possible, something flashlight nozzles are unconcerned with, as those nozzles only reflect and focus light which cannot be accelerated further. Is my understanding of rocketry nozzles correct?

Why could'nt a moon have it's own magnetic field? Does'nt it only need rotation with a molten iron core to generate a magbetic field? Or does mass really make a difference, so that only planets can do that? Unless you got some weird moon made out of neodynium ore (would be fun times trying to land a spacecraft there though).

Through the axle. Or we may not even have to use blood? Maybe it's an inflatable bladder like a tire? Maybe it's about the size of a motorcycle with two wheels? The body plan itself would be Soft ans squishy spheres joined together with necesary arms and manipulative digits. Since soft squishy sphere bodies can take a 4g fall easier than a 5ft tall upright human ever could.

Actually I don't. My scifi universe...so my design. Cosmic accidents are without purpose or design. A created scifi universe is neither, as it has a clear purpose and design. I just design what I want and go from there.

I don't. I used to think it was cool years ago before I looked into the physics of it,and concluded it was impractical to impossible with regard to conformity to scientific understanding. By the way.. a 3g or 4g Earth creature would be well suiited for being stout... with wheels instead of legs. Not like anythimg you've ever seen in biology, but desperate times call for desperate measures. Distance to 4g fall hitting the ground is less, so it's a win-win design.

Winged humanoids are popular in scifi, but due to the square cube principle (weight increases faster than strength), it's a nonstarter. I have seen people say... but what if their world is lower gravity with a thick atmosphere? A few challenges there that I am not sure can be overcome. 1. The moon Titan is such a place, yet I have read that the reason it's dense gases do not boil off and evaporate into space is because it is so far away from the sun. So sure, people could fly there... and get frost bite in minutes or less... even if air was breathable there. 2. Moving a Titan-like world closer to the sun to improve the frigid temperatures I have read would make the gases evaporate away into vacuum, since the gravity of Titan is rather low anyway. I do not know if this is true, but I suspect it is, since our moon is larger than Titan and is not holding an atmosphere, likely because it could'nt, unless the gases in question were the heaviest you could find so they would hold more readily to the surface That's one planet type. Anymore you got? Or wanna discuss.

Laser assisted launch can be done using light craft, using either laser or microwave beams. In tests, is observed that higher the crafts flew upward the more u stable the craft became (toppled over a lot). Yet I think this could be fixed with a sufficient number of lasers or microwave beams targeting the craft. So basically, with sufficiently powered lasers you could launch anything you want from Earth no matter the size. However when laser beam heat is too intensr, you need active cooling. So that again involves burning some propellant. But overall you could launch a lot of small spacecraft and build a big one relatively quickly in orbit using this system. EDIT: If laser degragation over distance is a big problem, just hook lasers up to a floating baloon network of helium balloons tehthered and powered via ground stations. Gives the lasers more range. Traveling to other worlds: Ideally you're just going to do some ISRU, no matter how many weeks it takes on your small SSTO and then go back to orbit to meet the with the mothership, which itself is made of smaller craft assembled in orbit via laser induced/air plasma/along with LOX or methane augmented propulsion rocketry. If the world is not habital then use a robocraft SSTO for this. Only send down people once a habitat has been actualky constructed where they can live. If the cosmos is filled with Earth worlds like popular scifi often depicts, you can send people. Do note that sending them back to orbit will be an ISRU fuel waiting game. Unless you have drop some AM powered floaty lasers on an ocean and have enough spare propellant to reach orbit again with your SSTO. You may discuss the viability of this in the future. Provided we crack sustained fusion or good antimatter production and storage then it means you need less lasers to do the same launch, just enough to keep craft stable. You may discuss. EDIT: Even if the tech is viable, future humanity would have to be more mature than current humanity. Since a launch system like this, indeed any good launch system can be weaponized.

For me it's breeding across species lines. Since: A: The likelihood of offspring has the odds heavily in the negative zone. B: Even if you do manage offspring the likelihood of them being odd looking via size or some other way like a freakshow is high. This happens across several jaunra's of scifi. There is even precedent for stuff like it in ancient literature. For example, in greek foklore the chief god Zeus had several illegitimate children without consent, and even biblical angels had offspring who were giants. In a way, scifi aliens and superheroes both are substitutes for the gods of old literature.

Reasons to colonize no-man's land when Earth-worlds and FTL warp exist are: 1. Your terraforming is THAT good. 2. Strategic. If at war with Earth, colonizing Proxima Centauri planets is a good base of operations to launch supplies from. 3. Trade operations. Sometimes some systems really do have a surplus of valuable ore. Maybe there are shiny planets with so much gold dust in the dirt that it shines from space.

It does not have unlimited range. It's range is limited by how long it's engine can last before overheating or malfunctioning, something quite possible given the changes in weather tempertature as it travels for miles on end. Even nuclear reactors expire at some point. I will grant you that if the engine is made of sufficiently heat resistant materials that it will outlast all other rockets in the air.

Could not make myself read the entire mini-book of text... but I will try to see if I understand this... feel free to give me the Cliff (short form) notes version. Macrons? ??? Bits of sand shot at high velocity? Ok now it's starting to make sense. So you're saying it can be used on a rocket or as a weapon? The weapon I am less interested in, as just about anything with an engine can turned into a weapon in space. And if I understand it right... you're saying the sand can be shot across space propel spacecraft far away like some kind of propulsion beam? So it is a space only tech I gather? Not good enough thrust for launch to orbit, but orbit space speed is stackable so it's all good?

You make a valid point. With stuff like FTL hyperdrives being cheap enough for interplanetary trade in mere days, they probably are more challenged by massive planetary modifications and add ons. I would hardly be surprised if they had some type of vacuum reaction engine and stuck it on the backs of asteroids and small moons for thrust. Still... the real reason I consider this is basically how to find a way to beat gravity and get massive payloads up without cheating make believe. In space I don't mind making up stuff, as it is required to go anywhere interesting in a reasonable amount of time. But lifting off a planet like Earth can be done several ways, one way among them being an MHD... which strangely enough, if powered via antimatter and it rocket engines too, it could do a air rocket/air MHD combo to orbit. So any somewhat more grounded approach to the challenges of SSTO flight is a composite solution... which in any case will require burning less propellant since the MHD is helping with fligh in tandem with the rockets.

Setting has hyperdrives too... so go figure. Everything is justified by plot needs. But if anyone wishes to utilize SSTO's as common place in scifi it requires stuff we do not have. It is not safe otherwise and thus it's use cannot be justified as common enough to trade with across the starry heavens. Because with only known abilities what have ya got? Project Orion SSTO variants with all the fallout issues, and ludicrously expensive antimatter vessels that would make Kanye and Elon both go bankrupt.

I thought specific impulse was how long propellant lasted? Or is it a measure of how much thrust you can get out of your propellant?

The engine is. And how much atmospheric cooling you get depends on other factors like: How big are your intakes? How heavy is your vessel, as heavier vessels take longer to lift off, which means unless your vessel has a whole lot of intakes on it, it will have the least atmospheric cooling during the initial launch phase. As it speeds through the air it will get more cooling from oncoming air. But for the initial liftoff you should probably use propellant mixed with intake air. There is a certain sweet spot for air intake speed cooling, especially when using antimatter. I You need enough intake air otherwise your engine melts or you must inject cool liquid hydrogen.

This is purely for fun, as it won't affect my plot direction whatsoever. Which of my scifi created humanoid races would you prefer to work with and why? Which would you not want to and why? Based on their behavior only? Race 1: Take a positive view most all the time of situations, but can still adopt a negative view... it just takes considerably more to get them there than it would a human. Usually by the time they get negative a human will be inclined to tell them, "It's about time!" These aliens are mortal and therefore have adopted a negative view of death, but cushion it with the philosophy of dying a better person than they were, or no worse than they feared. They also have longer than human lifespans Race 2: Accept, support, and provide what is true. Everything that cannot be verfied is viewed as speculation or theory. They never assume anything, but still put their trust in others with the understanding that there will be consequences for failure to do as agreed upon via contracts. Contracts are sacred. They can theorize and speculate, but are incapable of lying. Rather than saying I can do this or that, they are more likely to show you awards they have received that can be verfied, or demonstrate their skill if they have the time. Lifespan is shorter than human, about that of a dogs. Which also means their bodies mature faster, but their minds mature at the same rate. So a 3 year old is actually in their late 20's. By the time they reach 16 human years they would be in their 80's. Race 3: Naturally inclined to repay debts owed, and not doing so means they hate you. Lifespan is very long, longer than race 1. Tend to prefer warm environments, since they are cold blooded. Race 4: View optimal physical fitness for one's occupation as the highest virtue. To do otherwise is considered sin. For example sumo wrestlers would be OK, since their job requires it, but anywhere else people that big would likely be frowned on or looked at with contempt. Indeed... that is actually a form of punishment... makng people fat in prison, which means they will work hard to work it off upon release. Lifespan is human. There you go... you may answer. Last

Good point. So an antimatter project pluto air breathing rocketship could work in theory. It is still thermally limited, which means pound for pound,, you can ship more payload via orion style than you could with rocketry of any kind currently known. Big advantages require greater risk. But I also assume the containment chambers are advanced enough to convert the AM back to normal matter... at least if I was making scifi. Making antimatter would be just as easy.

AM bombs beat nuclear bombs since you can scale down farther and still have high yields that equal or even surpass nukes. Rocketry is limited by the thermal limits of the engine walls, which limits the amount of thrust you can achieve with an SSTO. A pusher plate allows for even greater thrust since the reaction is not contained, but outside and pushing the ship away. Thus you do not worry about a melting engine. Even the plate can be protected from ablation damage by spraying it with oil between bomv detonations. AM bombs are an ideal form of orion pusher plate propulsion. Rockets have limits that pusher plates do not... so that is why I propose AM orion drive submarine SSTOs.

This idea is borne from our current understanding of what physics allows for. The SSTO: Imagine a submarine with a nuclear pusher plate at the rear... but with antimatter/matter bombs instead of nukes. It also has propeller engines for underwater propulsion on opposite sidewalls of the rear hull. I have read somewhere that AM bombs actually leave less fallout than fission based bombs (all 'known' nuclear bombs have a fission bomb trigger). Even though their power is greater. Max Payload: 40 tons cargo. Max Crew: 40. Launch scenario: The sub/SSTO leaves a coastal docking port until it is several kilometers from the coast (regulators will have work to do here). Then it releases a bomb, waits for it to sink far down enough for safe detonation, and then the ship rises from the water, nose skyward and emerging partially from the ocean using propellers only. Then it detonates the bomb. The thrust propels the pusher plate sub out of the water, and repeated detonations allow it to make orbit. Landing: Landing by detonating AM bombs is suicide, but landing with belly rocket thrusters using nuclear or AM heated chemical propellant mixed with,an air breathing system most certainly is not. Still... it's gonna land in the ocean. Then propel itself like a sub to the nearest dock, unload, and repeat the entire process. EDIT: Just one example of what we could do if we had working amounts antimatter and a reliable abd safe compact way of storing it. What you would not do... ever: Land on land. Unless you had to. Since the landing is not the problem, as you have propellant alloted for that. Relaunching is, since anything within a few kilometers will be obliterated. The ocean don't care... well PETA might be upset for the fishies... but we will have to ignore their wealthfare to do this... at least whoever is in the blast radius. Since I do not see any company herding out the fishies before launch. You may discuss.

If that is reality, then you can also nearly forget fusion rockets, as the magnetic fields to contain the reaction would be lab facility size anyway. You can also forget any MHD ionocraft drive scaled up for the same reason.

These are the limits of making uber electromagnets as listed below: Increasing current density is limited by Joule heating and increasing the magnetic field strength is limited by the cost, size and weight (as well as technological limitations) of electromagnets and the power available to feed them.[14][15] Cost is only an artificial factor, but the others are serious show stoppers. Why do I even care about magnets? Powerful magnetic fields can be used for many scifi technologies... like rocketry and maybe... just maybe... get a profitable fusion reaction going. One site claims scientists created a solid state electromagnet that can do 90 Tesla, although it will break itseld in time. So I thought... are magnetic fluids possible? Uber magnetic fluids? Does current physics understanding allow for it? Because if so perhaps that is what we will use in the future. Since I really don't know how you would break a super magnetic fluid beyond boiling it. You may discuss. EDIT: Wow.... I suspected as much. https://www.google.com/amp/s/www.sciencealert.com/scientists-have-printed-droplets-of-permanently-magnetic-liquid-and-boy-is-it-trippy/amp

Only if taken to extremes... since such drives expend fuel so their are limits on range without refueling.

Scenario: Three types of scifi hyperdrives are available to you. Class I: A small drive that can be fitted on small vessels. Hyperspace travel time is a lightyear covered per 30 minutes. Yet in reality, outside 30 days passes for every 30 min of hyperspace travel. So about 2 hours would get you to Proxima Centauri, but when you arrive 4 months will have passed. Class II: A medium size drive for medium size vessels neither gigantic nor small. Hyperspace travel is a LY per 15 min, outside 15 days pass per LY traveled. Class III: Large hyperdrives for large vessels. Five min per LY in hyperspace, equal to 5 days passing outside per LY. Throttling down: You can also throttle down the hyperdrives to go lightspeed, in which there is no time variance. Useful mainly for interplanetary cruising. My analysis: Class I hyperdrives are best for explorers I think, and Class II hyperdrives could be used for cheaper shipping for longer wait times, but by and large the Class 3 hyperdrives would reign supreme in shipping. Big ships would be the fastest ever. Did I miss anything that you can add to my analysis? EDIT: I have no clue how close these travel times compare to modern sea shipping, but I have a feeling they are similar, and faster in some cases. EDIT 2: I think the ability to skip several months into the future within a few hours woukd be nice ability to have, if only to see rapid progress. Whoa... I just figured it out! Passenger ride fares would be a healthy source of income. Don't wanna wait months for your package to arrive? Hitch a ride in hyperspace and the wait will only be a few hours. Sure, months of time will pass outside, but who cares? You want your package ASAP!