Spacescifi

This is kinda for laughs, partly for ingenuity. You are on a scifi scavenger hunt in the Star Trek universe. All you have to do is acquire specific items. You cannot buy them though. You either find them, borrow them... or um... you know. Items: Klingon's personal knife: A borg implant: A phaser: 7 of 9's catsuit: Klingon bird of prey: Could you do it? How do you do it? Ask politely? Or do you die trying?

Does liquid nitrogen have the same issues of liquud hydrogen? Being hard to store because of vaping away? If not that's great, somebody can try that one day. Nitrogen makes a pinkish flame I read, but a blue one at peak current... whatever that means. Liquid nitrogen is awesome though. Since if he can do this with hardly any preparation, then a prepped air breathing NTR with liquid nitrogen could do wonders.

I too find it interesting. Somewhere I read that nuclear air breathing SSTO'S are possible, inasmuch project pluto did work. One could even make the open cycle exhaust safe by shielding the reactor and using heat absorbed from the shield to create the heat for plasma jet thrust. Therein lies the challenge, since shields must be great heat conductors but not melt. That is why nuclear lightbulb drives are still on the drawing board. Even if it could solve the heat issues, it has been claimed by some that a nuclear thermal air breather craft would use up all it's uranium for nuclear reactions within days. That is the price for high thrust nuclear craft, you run out of uranium faster. At least that is what some say.

I know, yet there are circumstances where speed may not be totally matched where inflatable shielding can be useful. Namely rescueing astronauts or catching wanted debris without fully matching speed to save on propellant.

I was thinking to use it sanely, for intercepting objects that I have adjusted my speed and trajectory for already. Something orbiting in the opposite direction hitting my vessel would be unhealthy to say the least.

After watching Ad Astra and watching just how hard Brad Pitt collided with spacecraft, I started to think about inflatable shielding for spacecraft. I know it goes up as a rocket, but it is also possible to inflate balloons all over the 'spine' (the rocket body) of the spacecraft. My reason is twofold. 1. So astronauts or debris won't puncture the hull, just transfer momentum. 2. You could ram/push/catch stuff at certain velocities without taking damage to your spacecraft. Newtonian bumper carts. EDIT: I am finally begining to realize that the future of spaceflight will have shapes and designs yet to even be seen in popular scifi. I actually now see a spaceship as a hard rocket surrounded by plushness. Seems to offer benefits over the standard hard only spaceship. Even in a worse case scenario of a crash landing, inflatables hugging the hull could make a gliding descent more survivable. A more soft landing. Because the inflatables will cushion the blow before they fail. Thoughts?

Here's an idea: Take a solid propellant and forget about the solid oxidizer powder. Instead use the heat of a nuclear reactor to burn the solid propellant, which is poured into the reaction chamber as needed. Has this ever been theorized, or is it just a bad idea for reasons I am not aware of, but will likely learn from you or another? Thanks.

LH2/LOX will evaporate long before even a month passes is my guess. The spacecraft is already in orbit and has smallish fuel tank. Antimatter is out for this discussion, as well as theoretical metallic hydrogen. Only modern fuels.

Let's say all you care about for a spacecraft is maximum thrust to weight ratio. You need not be concerned about good delta v, all you need is something that will store for months on end and when high thrust is required, it can deliver. This is essentially an orbital interceptor spacecraft and is already in orbit. What propellant gives the best the best thrust to weight ratio? LH/LOX is out, as it won't store well. Liquid methane requires cryogenics that will cut into the mass fraction that effects what little delta v you have. Hypergolics might work, even though toxic, and monopropellants also sound good. Solid propellant could work too, although it makes pulse firing either not possible due to one long burn out, or harder to design for. Know what the funny thing is? Chemical rockets have better thrust to weight ratios than NTR, except for the variations that tend to be unworkable due to operating at the edge of material thermal limits. NTR's have lower TWR, but make great for interplanetary because of better delta v. But an orbital interceptor only cares about one thing. Interception via docking with orbital spacecraft. Thoughts?

Yes and no I think. Yes: Nations who lack a way to toggle planet gravitational pull on/off are going cry out and say it is a threat to global security. No: Superpower nations will expand their military forces with nuclear rocket spaceships, all thanks to the power to toggle gravity on or off. The major powers may not go to war directly, but they no doubt would fight proxy wars and hammer down on old but weaker foes who would either placate them or fight to the bitter end.

Gravity. Unless there is a way to do it I am unaware of, the method we use thus far to beat gravity requires either throwing mass or energy away. Rocketry. What you are proposing I tend to view through the rocket lens. Thinking it needs some external medium to push against if it is'nt throwing anything out (a car pushes it's wheels against the road). Forces tend to balance each other out, and something must be used or expelled to get anywhere. Otherwise forces balance out and all is static. To push a magnet upward with itself sounds... not possible. As far as I am aware, some external reacting medium is required for any motion that is not rocket derived.

Um .. we only wish that were true. Gravity is the enemy of space flight. If we could somehow toggle it on/off then all of our nuclear rocketry would be more practical to utilize. As matters are now, great thrust means great heat, which requires great cooling. Which makes great weight. We could have ALL the benefits of nuclear rocketry if we could negate the pull of Earth's gravity. As we could then pile on the cooling equipment with minimal engine thrust losses. I know that is not possible now, but if it ever is... it would be game changer.

So active cooling then... aww forget it By the time we add the cooling equpiment the extra weight offsets the thrust benefits of the aerospike, so we may as well stick with ordinary bell nozzles. Aerospikes and all the many types of nuclear rocketry would work a lot better if we invented a way to block the effect of a planet's gravity. Then you could pile on as much cooling equipment as you wanted and still launch without using up too much fuel in the process. We could lift this off the planet for example if we could shut off gravity or toggle it on and off. With modern technology. All we need is a way to toggle gravity on/off.

Both... and yet more.

I am not worried really. NASA definitely won't be the force behind the future of human space exploration. But I am positive we will... get out there in the future when conditions for space flight are far more favorable than they are now.

I did not title the video. Someone on youtube did. I just posted the shortest video on Zubrin that came up and it was this. Really, NASA being government run tends to shift it's priorities. For example... what do you think goverments care most about? Colonizing the solar system or maintaining their power on Earth? I honestly think space agencies the globe over are far more interested in orbital spy satelites, GPS, early warning satelites, and ICBM's than they are about space colonization. Since they have the capacity to do more but would rather protect their own soveregnty from attack by rivals.

I know about wedge shaped linear aerospikes, but I tend to think that the spikey aerospikes are better looking. Is it possible to build a gimballed aerospike? I want to know, since that would simplify aerial maneuvers without resorting to RCS thrusters while flying around in the atmosphere before reaching space. Also, what is the best material we could build for a gimballed aerospike that is heat resistant? Tungsten/titanium alloy or something? Diamond tungsten alloy (if that is even possible LOL). Thanks for your answers, have a great day.

Haha... deep thoughts you made. But really and truly, it's all for fun and fictional. If anything, it's more art imitating life than anything else and the oddities of trying to cope in a strange universe that is like ours but dialed up to 11... because scifi.

That depends more on the ethics of the civilization involved. Inasmuch they only lack anger and sadness, and they still retain human curiousity, I do not see them being genocidal or even xenocidal. If they met anything like the B5 shadows though... yeah. They would go full xenocidal on them. They are an obvious and unrelenting threat.

Fusion is near impossible to implement for nearly the same reasons antimatter is. Storage. Stars cause fusion in their cores with a star's worth of mass and pressure and heat to cause fusion. We do not have that. Current schemes use magnetic fielda to hold the plasma, which tends to slip out on a regular basis, hitting the chamber walls which causes the plasma to cool and kills the temperature required for a sustained reaction. So in short, you need a high temperature (often higher than the core of the sun) snd magnetic fields that won't leak out plasma.

You have a point. You did what I asked for. Your analysis. I guess perhaps I was a bit vague in the original post. Primarily my intention was to study their behavior to see posible types of behavior that may occur in their society. Which is valuable to know in a scifi setting with multiple races where interstellar travel is casual.

Never said they evolved, nor did they. Races can have whatever origin story a writer wants. Even so, their origins won't really play a major role until they come face to face with possible extinction anyway.

Hold on. The grays (have grayish skin but otherwise virtually human with a few extra features) know and possess: Joy Love Fear Disgust Surprise What they do not have the capacity to feel are sadness and anger. But yes, you have got it right that bargaining with these aliens can definitely be done if under the right circumstances where both sides get something they want. As for the robber, there is no peace treaty for that. That is what law enforcement is for. Understand that without anger, fear is often the next best thing to replace it and motivate them. As for robbers, some societies have EVERYBODY packing pistols for that very reason. Just in case. Others do not allow weapons at all except by guards, and guard bots which are common.

Actually that would make an excellent scifi story. Zubrin is an alien in disguise who is so disgusted with NASA's primitive human space program because his starship is on the surface of Mars. All he has to do is get there and he can finally leave this ghetto civilization and rejoin his Star Trek level Federation solar system with replicators, holodecks, and green space women! That was a joke. I do respect Zubrin and do not think he is crazy. But I could not resist. His anger and and frustration is so palpable it begged for me to fictionalize it! However this: He is compelled by various assumptions, which if actually false, he would be supporting wasting a lot of time and money to get an answer that we can guess already. The movie Ad Astra is uniquely poignant about this. No I won't spoil the ending. But I will say this. When you look up at the sky at what is far beyond your reach, remember to look back down at what is near and reach for that.

I do not know Zubrin. Nor did I know he was alive. At any rate, here is a video of him. He does seem... literally mad here (not crazy, just angry). On some level I sympathize with him. Since he is implying NASA could have done better with developing new space technology for colonization than they have. True they could have. Yet unlike Zubrin, I am not set on colonizing other worlds just yet. We are not ready. Not yet anyway as race. One day, I have faith that we will be, and then I will seriously consider colonization of other worlds. Right now all we would do is transport our creed and greed to the stars. Our love too. Have to crawl before you can run.