Spacescifi

"What do you want from us?" That would arguably be the most important question I could ask even though I would have more. Since one does not come all this way to make contact and leave it at that. At least I know a human would'nt. Assuming they would have at least that much in common with us.

Such factors I do not doubt were involved with european exploration and colonization. Yet for scifi creation, I use god, glory, and gold as I define them for a template for humanity since it is helpful. Aliens I usually take for granted that they also have those same desires, since who wants to read about a person who does not attempt to solve or answer what is currently impossible? Who wants to read about a person who does not desire to be liked by others? Who wants to read about a person who does not desire to profit by beneficial experiences or things? No one, because the only person that fits such a description perfectly that is real is a corpse. Humans want to relate to their fictional aliens. I just make them different than your average person so they can still pass for alien in how they behave.

Money? AKA the human desire for profit. In which case when money becomes worthless it would be the basics that money buys, food, clothing, shelter, and any luxuries you can achieve. I summed up the human race based on the three main reasons europeans conquered north america. God, glory, and gold. Bear with me, since as I define them they mean more than they appear to at face value. God: A human desire to solve/answer questions/problems we can neither answer nor solve currently. Glory: A desire to be liked by other humans. Gold: A desire for tangible benefits or experiences. My point us, to the extent that the fictional aliens fulfill these desires, they will definitely hold the human interest. Up until what makes them act different than us becomes something we do not want to deal with.

A thermo-fusion plasma rocket would be the one The idea is to use free air as propellant by shunting it over the fusion reaction, the use rocket fuel once the air thins out. Again shunting ot over the reactor for greater thrust.

Fusion is seen like the holy grail for rocket scientists. With it SSTO scram jets would be easier to propel (although we could probably do it with a fission reactor spewing lethal exhaust). The question is, if we ever managed to make a fusion powered rocket with a sustained fusion reaction, would the exhaust be relatively safe in the air? Or would it spew radioactive cancer death like nuclear thermal rockets? Bonus question: Antimatter propellant combustion rocket exhaust? Safe in the air or not? I think not, since gamma rays. Unless you know of a way to make it safe? What do you know and say about all this?

In the animal world, goats and sheep often live together. That is arguably a close analogue for scifi alien and human interaction. I read that a goat is happiest among his own kind, and likewise for sheep. Granted if they were raised together they may be friends. But even then it is said that social species are happiest overall with their own kind if it can be achieved. My point is, even with humanoid aliens, provided the writer does enough work to make them act differently than your average person, that would be a line of division right there. Imagine for example humanoids who kill and eat their prey without cooking it? Humans could respect that, but your average person won't want to see them take a baby chick out of his lunchbox and do far worse than ozzy osbourne. Just like humans may like and respect their pet cats, but would never adopt their strange ways ourselves. That goes both ways, as the aliens would no doubt feel the same about us. To me, fictional aliens can in a some way, teach how to adapt to cultures not our own. Although granted, stretching this to the Nth degree of what humans can and cannot tolerate can easily be both comedic and interesting. For the writer and the reader.

Neither had I, indeed, you understand it better than I! Yet in conclusion, I have decided to only use rockets for RCS. Scifi abilities on spaceships I prefer when they have obvious side effects. A cost as it were for defying our real understanding of physics. So to ascend to space (not orbit) my ships will use an antigravity field. The side effect cost is that the ship repels everything that can fall due to gravity away from it, everyting outside the ship, up to a certain foot radus. The rate of repulsion is the same rate of acceleration the ship is repelled away from the planet with. So no one should be near the ship during launch for dear they will fall backward several feet. Inside the ship the effect is the opposite, as the crew us pulled at toward the center of the ship at the same rate of acceleration the are being repelled upward. Thus they feel horizontal g-force while ascending upward. Once the ship clears the air up into space the antigravity drive will cease to accelerate, as it only accelerates away from a planet because detects the atmosphere and ground as one big object to repel away from with the shortest path (up). In space the antigravity field will still pull the crew inward at whatever number of g's they are repelling outward, and it can be used to actually push stuff away from the ship, while pushing the ship away, (thus accelerating it so long as an opposing object is within the field's radus). One can actually push stuff continuously this way since with the constant acceleration drive from via vacuum jets, one can accelerate enough to not be repelled away as they push asteroids and whatever else with their antigravity field. Since this is supposed to be alien technology anyway, and they have FTL, and fuel tanks taje up cargo space, I decided to just use it for RCS. Granted my ship's cannot fly around like airplanes in the air like star wars, but they are perfect for space. Besides, to fly any odd looking non-aerodynamic ship the way they fly the milkennium falcon would be both uncomfortable for the crew and inefficient. Imagine what happenst to the cargo when they do a barrel roll? In space? No problem. And the design is so inefficient for air travel that it screams fiction to me. Granted some may care less. But I am doing it my way because I care about that kind of stuff. Aliens I think are supposed to be wise, and making a ship that is shaped so that it will fly inefficiently through the air, even if the engibes have endless fuel, makes no sense to me. So my spaceships will only perform best as spaceships.

That was a typo. By the time you read this it will have been fixed.

Good informative post, yet combustion should not be an issue in my scifi because they just run the propellant over the hot reactor/power core. Could be fusion or something. That is enough to make a flame out the back end of the nozzle.So without combustion being a relavent factor, does that change any of your previous analysis?

So based on what you said, an ideal scifi ship rocket nozzle configuration would cover the entire rear end cross section of the ship with rocket nozzles only as big as an adult human hand. That way you can do even more precise speed control. Good idea? If not why not?

Scifi spaceships have excellent delta v, so why do they have multiple rocket nozzles? A few reasons below that I can think of: Thrust vectoring. Also, to add to that, turning off some engines while leaving on others is a way of reducing thrust easily. It looks awesome: Preferred style or imitation perhaps? Having googled it, the advantage one big rocket nozzle confers are: Fuel flow is better: Multiple fuel tanks linked to a single nozzle. Stop pumping from some of the tanks and you reduce thrust. With multiple nozzels attached to a single fuel tank, it takes longer for some of the fuel to reach some nozzles than if all fuel tanks were linked to the same nozxle. At least that is what I read. In scifi though, all seems equal. For example, if you have two spaceships with virtually endless high thrust delta v, the advantage of multiple nozzles over one big one appear minimal. The only advantage I can think of in that case that multiple nozzles would confer is thrust vectoring. What do you think?

I tend to agree. Every watch Dust shorts? They are short shows, but they tend to use tech as a backdrop and focus on the characters as well. Instead of wondering what fictional tech can do (a fool's errand in my opinion since it is'nt real), they focus on WHAT would this charactet do, and by extension, you the viewer. Check thid video out, it's one of the best Dust has to offer:

Yes I considered that, including thermal jet engines (shunt compressed air over the ship's reactor or power core and simply use the resulting hot plasma as reaction mass). I did not nention it at first, but the rocket engines also serve as backup if the vacuum jets are damaged or disabled. An air breathing jet engine is added weight for no returns in outer space. Meanwhile, a rocket engine has a simpler design (I am using a mettalic hydrogen flake/ice slush mix as fuel). If only it were that aimple I would bite the bullet as you say. Travel time is only a fraction of what realism entails. And i won't limit myself in that way. Because this is what it entails: Cancer: Unless you rely on either fictional materials or a ship so heavy with thick walls that it would probably take it a month just to reach the moon! Running out of fuel: How do you refuel? Gas giant skimming at orbital velocity is hardly safe. And I understand that shuttlecraft can do skimming for a mothership and return, but unless they have some uber plasma scramjets abd cad take the atmospgeric heating repeatedly, they will need to burn some of rhe gas they are storinfg for the mothership. Zero habitability: Antiartica is a more reasonable choice if habitability is a concern. All known worlds in the solar system are death traps. Thus it defies my logic for any of them to have large populations if modern tech is all that is available.

On the one hand I understand. Rocket plumes look awesome. We also have a good working understanding of fuels and how rocket engines should look. That makes them easier to write than a fictional drive from scratch. On the other hand, when scifi spaceships (star wars and many more) use what appear to be rockets to go everywhere and back, it does not sit right with me as a sci-fi writer. Knowing full well that staging is always the way to go if using rockets. It is the only way to maximize fuel efficiency beyond weak ion rockets, by shedding extra rockets when they go empty. So as not to be lugging around extra mass which cuts into fuel reserves harder. I finally came to a solution. If I did not use rockets at all it would make all the research I ever did on them seem pointless. So I included them, even though my scifi has SSTO ships that can reach orbit using both oddly shaped choices (like saucers ) and practical ones ( long tube like a passenger jet minus the wings). Rocket engines are used ONLY for leaving an atmosphere. But they are helped along by antigravity shielding which shields the ship from gravity, allowing it to float like a balloon in the air. With that assist, even saucer shaped ships are a viable means to escape the atmosphere. In space itself, the ship uses a uniquely shaped space jet drive. Which uses vacuum as reaction mass, and space has plenty of that. For propulsion. FTL drives are easy by comparison and did not require nearly as much thought. Yet what I enjoyed about ny solution is that it made space-mining resources more likely in my scifi setting. Since if you plan on navigating inside an atmosphere you need rocket fuel. Also if you plan on leaving in a reasonable time (floating like a balloon with antigravity would take a good while). Yet in space, the vacuum jets allow constant acceleration, and they are quite useful for travel to asteroids and landing on airless moons. Also for orbital insertion near planets. Which means you will get fuel depots that ships can ressupply and be ressupplied rocket fuel from. In space and LEO of any atmospheric planet in frequent use. For that matter, with a long enough hose a ship could suck up gas from a gas giant while it slowly flies above the atmosphere in space with it's gravity blocking shield up. That is my solution for the rocket issue in scifi. What is yours?

LOL. I would laugh hard if in a fictional work the aliens used an orbital laser to write a message on the white house lawn while the government is still debating how to respond. The message would read: MEET OUR DEMANDS FIRST. ONLY THEN WILL WE SERIOUSLY CONSIDER YOUR REQUESTS. WE ARE SERIOUS. VERY. VERY. SERIOUS.

I once read that war is just another form of politcs. Politcs involve measures taken to get what a goverment wants, whether when dealing with other governments or it's citizens (no mods I am not going to discuss political issues). When negotiations fail, out come the knives, or, war. That said, when fictional aliens wanna conquer earth, I think they should have something they hope to gain. For example, if rulership over mankind is desired, exterminating large amounts of the population that refuse to submit is probably a bad idea. Unless your weapons are so precise that you won't do any damage to human allies. And also if you can effectively protect ALL your human allies. Doing that is for the most part impossible unless the aliens in question are verging on godhood. Even superman or a whole army of supermen cannot be everywhere at once to save people. If all the aliens want is resources or even slaves, it becomes a lot easier. Demonstrate orbital supremacy and do some orbital bombardnent of the ocean as a warning shot. If that won't get humans to cow to your demands, more bombardment on the right targets likely will. Bombarding civillian targets is a bad idea if it can be avoided. Did not work so well for Germany in WW2. It only earned them the wrath of the british. How about you? What effective ways to conquer earth would you recommend for fictional aliens?

The first race that relies on specific fruit for their reproductive cycle actually has a bit more to them than I am letting on. But only in a physical way. They can climb walls. Courtesy of octopus suction plates on their fingers and palm, going all the way up the forearm to the elbow. To do this they excrete a sticky adhesive through palms and fingers that looks akin to a shiny iridescent snail trail. Also have them on ear lobes, fringes of ear, knee caps, and the soles of their feet. Their home of origin is a mars like world but big as earth and an atmosphere lime earth's as well. The sky is pinkish though near the the horizon (closer to the ground) and fades to blue as you it goes higher. Grass is red from the high iron content, since red us like green is on earth. The aliens themselves have a much higher tolerance for cancer than us, what with eating plants made from soil with lots of rust in it.

LOL. If only it were that simple. You would do better by laser induced coronal mass plasma ejection though. Blast the sun with an effective laser and you just made a giant plasma rocket! May be hazardous to earth though, what with basically a constant solar flare going on.

Which means what? I well know for the scale of ore processing done on earth to be done in space you would likely have to import some resources found most abundant on earth. It is rather hard to do that level of processing using only asteroid resources. Even if I had metallic hydrogen rockets and antigravity shielding to make my scifi ships immune to gravity, it would still be a challenge.

Yeah, trying to justify the why of asteroid mining makes little sense unless you need it to refuel and or equip your spaceships in outer space. Without going back down to a planet's surface.

Because although it is realistic, it takes longer? With scifi mining ships you would get a return on the investment of making the ships much sooner. EDIT: Actually a proper ming vessel could be shaped like a huge hollow cylinder with a net on the front. Just fly thru the blown-up asteroid fragments and collect. A much better design than my previous one. When it comes to jobs that spaceships do in space, optimization is preferred to get the most work done. Who cares if my starship looks pretty if it cannot do the work it was supposed to do as efficiently as it could have with a better design?

My way is partially realistic. What is not is how fast they can reach the asteroid (using a warp drive to cross it's orbital trajectory, and a constant acceleration drive for intercept. Extraction of ore and minerals is acomplished by blowing up the asteroid into chunks, then releasing a funnel dragnet behind the vessel and quickly flying through the fresh asteroid field that has been created. Low-tech but it works. Last step is to warp back to a LEO ore processing facility and let them do the processing work. While the ship goes to mine more. I really like using a net because it does not limit the quantity of ore by a spaceship's cargo hold, only the size and strength of it's funnel catching net. What method would you use in scifi and why?

Well I will just go the route of good heat resistance and an infinite fuel source. Basically the only real limits to ship size with this scifi method involve whether or not you care about ever landing again without bombing your own ship repeatedly with tbe blowback of the ground's blast wave.

So what you're saying is, if fuel was not a concern (in scifi it often is'nt), this would make a viable albeit destructive way achieve orbital speed?

Consider a scifi spaceship that literally has the photon energy of the SUN. Would that give it enough thrust to get to orbit or not? I know photons are weak for thrust, but a sun's worth of photon's is quite a bit to throw behind your vessel. The ship weighs 200 tons and is fully loaded with 25 tons of cargo. So it has to lift 225 tons into orbit. Can it do it? What do you think? I think it would work, given that the old plans called for antimatter, which still would provide less photons overall than the photon equivalent of the ENTIRE sun. Yet that also means making a rocket plume from the ground itself at liftoff. The photonic exhaust is going to burn for miles.