Interstellar Travel Modernization

[Bill Phil]

1 hour ago, Nibb31 said:

I pretty much stopped here.

Getting into orbit is about reaching a certain speed, and chemical rockets are simply the best we have for converting an energy source into velocity in a vacuum.

Your spaceplanes and motherships still need to convert some sort of energy source into velocity, so unless they are powered by magic or you live in a fantasy universe, they are still going to need rockets.

Also, spaceplanes are a pointless waste of mass. You don't need wings in space. They just eat up your payload fraction with structure, moving surfaces, heat shielding, hydraulics, landing gear, etc... None of that is useful in space. So again, unless your spaceplane is powered by magic, you don't want to waste energy by carrying all that useless stuff to orbit when you could be carrying propellant or useful cargo instead.

 

 

Except that we have Orion as a concept. With development it could easily surpass chemical. And it's 50s tech.

[shynung]

2 minutes ago, Bill Phil said:

Except that we have Orion as a concept. With development it could easily surpass chemical. And it's 50s tech.

I'll go right over your head, and bring you the Nuclear Salt Water Rocket

12.900 kN at 6.728 seconds, provides continuous thrust rather than Orion's pulses, and it works much like a hypergolic rocket.

Sure, the radiation's still a problem, but if designed correctly, this will get you anywhere fast.

[RenegadeRad]

16 minutes ago, Bill Phil said:

Except that we have Orion as a concept. With development it could easily surpass chemical. And it's 50s tech.

http://i.memeful.com/media/post/BRkm0vw_700wa_0.gif

See, that was what I was against in my post.

But, I have second thoughts after reading Shyung's reply... Btw Shyung wouldn't that take some serious g's and how will it "brake"

Edited March 29, 2016 by RenegadeRad

[shynung]

2 minutes ago, RenegadeRad said:

See, that was what I was against in my post, that we can be advanced together but we don't!

There was a reason the Orion didn't make it to full scale production: Nuclear Test Ban Treaty. Put short, no nuclear explosions allowed in space. That pretty much closed the curtain on the endeavor.

And unfortunately, NSWR is still on paper. Orion used to have small-scale prototypes using chemical explosives, but that's it.

[RenegadeRad]

derp...

I still don't see why people disagree with the "mothership" option, look at that image, I mean its reusable and easily modifiable, upragable just like PC's. Orion and these rockets are overrated and feel like consoles xD 

[PB666]

23 minutes ago, RenegadeRad said:

kek then, I did say that I gave this idea so that you guys may science over it and make it real... Im not good in rocket science 0_o

http://i.memeful.com/media/post/jRj3pDd_700wa_0.gif

Wiki pages -  These are the basics for understanding how things work in interplanetary exploration.

momentum    (https://en.wikipedia.org/wiki/Momentum) 

[delta]V (https://en.wikipedia.org/wiki/Delta-v) [Tsiolkovsky] rocket equation
     delta-v budget
      Oberth effect
     Specific impulse (I_sp), effective exhaust velocity

Ellipses and orbits (used to be discussed alot but most everyone uses resources now that make this easier)
       https://en.wikipedia.org/wiki/Conic_section Defines circular, elliptical, parabolic and hyperbolic orbits.
       eccentricity, e 
       The following are defined in the conic section  
               major axis, minor axis latus rectum resulting in the following key orbital terms
               semi-major axis (a), semi-minor axis(b) and semi-latus rectum(l)
       mu (greek m, looks like cursive roman u) - is the Celestial gravitation constant  is Mass(object) times the Universal gravitation constant.
       Keplers laws of planetary motion (must read)

1. The orbit of a planet is an ellipse with the Sun at one of the two foci.
2. A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.^[1]
3. The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

      Note that the wiki pages are pretty fractured for information so there are many pages not mentioned here that will be required to predict velocities orbits, intercepts, etc.

      Hohmann transfer orbit

      Electric Propulsion systems (https://en.wikipedia.org/wiki/Electrically_powered_spacecraft_propulsion)
           Ion thruster (and the equivilents)
             
Ion thrust equations F = 2*η*P/(g * I_sp)

           Laser propulsion, Photonic Laser Thruster, Photon rocket. 
           Bussard ramjet

      Nuclear Propulsion systems
           Nuclear pulse propulsion
           NERVA
            Antimatter-catalyzed nuclear pulse propulsion    

These are the pages, I do not advocate any of these technologies except those I lend support for in the threads.

The links to the threads above more than cover the theoretical transport systems (Warp drives, black hole drives, Fusion based electric thrusters)

 

 

 

 

                

 

 

 

 

 

[RenegadeRad]

PB666 I love you man #nohomo 

[PB666]

5 minutes ago, RenegadeRad said:

derp...

I still don't see why people disagree with the "mothership" option, look at that image, I mean its reusable and easily modifiable, upragable just like PC's. Orion and these rockets are overrated and feel like consoles xD 

Before you can have a mothership, you first have to have a method to send a milligram from [whatever] between yourself and another  distant (extrasystemic) objects.

[shynung]

@RenegadeRad <- This is how you call the attention of a certain person.

34 minutes ago, RenegadeRad said:

But, I have second thoughts after reading Shyung's reply... Btw Shyung wouldn't that take some serious g's and how will it "brake"

Yes, the Orion design would experience thousands of Gs every detonation. That's why the design has a 'pusher plate' supporting the spaceship frame with several shock absorbers.

Direction of flight is to the right. Nuclear pulse units (bombs) are stored in the magazines, fired through the hole in the pusher plate, and detonated a certain distance away. Nuclear detonation shockwave hits pusher plate, propels spaceship.

As for 'braking', it's done like every other realistic spaceship: turn it around and thrust.

24 minutes ago, RenegadeRad said:

derp...

I still don't see why people disagree with the "mothership" option, look at that image, I mean its reusable and easily modifiable, upragable just like PC's. Orion and these rockets are overrated and feel like consoles xD 

You are likely correct that most future spaceships would probably be in a 'mothership-lander' configuration, rather than a single one-ship-does-all vehicle. Part of this is because rockets designed only for orbit-to-orbit voyages never need to worry about thrust/weight ratio, so they can be designed to have lower mass ratios (less propellant, more payload) by using a low-thrust, high-specific-impulse propulsion system. Landers, on the other hand, have to land and take off from celestial objects, so would need to carry higher-thrust propulsion systems, sacrificing specific impulse for thrust/weight ratio. This is acceptable, though, since they will spend most of their time being carried around.

The other part is that the rocket equation is unforgiving. In space, every gram counts. This gets into play in the Apollo moon landing missions. Someone at NASA figured that separating the lander from the main spaceship would save propellant mass, because the lander only needs to carry enough propellant to get only itself on the surface, and back up to orbit. Landing the entire Apollo spaceship on the moon would take prohibitive amounts of propellant, enough to design a larger, entirely new booster rocket.

As a result, I would argue that the Apollo CSM-LM spaceship stack would constitute a mothership-lander combination.

Edited March 29, 2016 by shynung

[RenegadeRad]

@shynung

You smart. You me friend.

One tiny bit malfunction in the shock aabsorbers and the astronauts go pulp. I feel like nuclear pulse propulsion is kinda like relying on something *cough* you can't "control". Oh and after playing KSP I actually realised that space travel is not just about aiming to something and firing, there are always gravity fields which form a trajectory of your spacecraft if you go from near them. 

I just feel that we rely on a lot of physical things or " anomalies" for space travel rather than doing some methods to get directly to place, the problem is resources though.

There are so many things capable that we can do, of we play KSP and also see real life physics, that's why I insist on disagreeing on my mothership idea. Agree or not , it has less cons than "one vehicle to do it all overrated rocket hippies" 

What's the deal all we have to do is to put the mothership in safe orbit while the "explorers" or shuttles already don't need much weight just some good propulsion and a design to withstand extreme environmental hazards, to land into a planet do stuff get back up attach to mothership, mothership takes a gravity assist and woosh we are back to home. We can make mothership like the endurance from interstellar or Hermes from the Martian or the discovery in 2001 so.

The simple ending is that we need fuel, solar panels are not that good, we need something which can create high energy through Star heat or we can make *childish mind intensifies* solar panels out of the newly discovered ultra black colour which absorbs almost all the light...

[Nibb31]

43 minutes ago, RenegadeRad said:

There are so many things capable that we can do, of we play KSP and also see real life physics, that's why I insist on disagreeing on my mothership idea. Agree or not , it has less cons than "one vehicle to do it all overrated rocket hippies" 

Beleive it or not, nobody disagreed with "your" idea of a "mothership". The idea of a specialized vehicle for long duration flights and a specialized lander/shuttle has been part of pretty much every interplanetary concept ever since Apollo. It's nothing new, and it's pretty much mainstream thinking. I really don't think that anyone has proposed an "all-in-one" architecture since Flash Gordon.

The problem with spaceflight is propulsion, on which there are plenty of threads that you are welcome to search for, read, and contribute to instead of duplicating those discussions yet again in this thread.

We have yet to find a propulsion mode that is both high-Isp, high-thrust, and compact, and light, and cheap, and politically acceptable. The entire space industry, which employs some of the brightests human minds, has been trying to find one for decades, so it is rather unlikely that a random kid on this forum is going to revolutionize space travel with a logo and a "mothership" concept that predates even Star Trek: TOS.

If you want to be taken seriously, you should drop the "interstellar" idea. Humans travelling between stars is pretty much out of reach of any foreseeable technology in the near or distant future as long as the laws of physics exist as we know them. It requires either generation-ships or near-light-speed or FTL technology, which might not even be physically possible, at all, ever. Those are concepts that are in the realm of science-fiction fantasy, not reality.

"Interplanetary" is the best we can reach for within the next couple of centuries, and it's plenty enough really.

Edited March 29, 2016 by Nibb31

[shynung]

32 minutes ago, RenegadeRad said:

One tiny bit malfunction in the shock absorbers and the astronauts go pulp. I feel like nuclear pulse propulsion is kinda like relying on something *cough* you can't "control".

It may seem like that at first, but a controllable nuclear pulse propulsion is possible. Choosing rate of pulse unit deployment, pulse unit energy yield, pusher plate angle, and more. In short, there are lots of things we can do with it other than turning it on or off.

32 minutes ago, RenegadeRad said:

I just feel that we rely on a lot of physical things or " anomalies" for space travel rather than doing some methods to get directly to place, the problem is resources though.

That's the only known way of getting there. One that actually works, might I add.

32 minutes ago, RenegadeRad said:

There are so many things capable that we can do, of we play KSP and also see real life physics, that's why I insist on disagreeing on my mothership idea. Agree or not , it has less cons than "one vehicle to do it all overrated rocket hippies" 

Well, as Nibb31 explains, the mothership idea has been pretty much mainstream these days.

32 minutes ago, RenegadeRad said:

The simple ending is that we need fuel, solar panels are not that good, we need something which can create high energy through Star heat or we can make solar panels out of the newly discovered ultra black colour which absorbs almost all the light...

Solar panels doesn't work on all EM spectrums, as far as I knew, so painting them black wouldn't help. It'd just make the panels overheat faster.

Also, solar panels get less effective the farther the ship is from the sun. One would need a generator of some sort.

9 minutes ago, Nibb31 said:

The problem with spaceflight is propulsion. We have yet to find a propulsion mode that is both high-Isp, high-thrust, and compact, and light, and cheap, and politically acceptable.

We have the solution that solves all the requirements above, except the last one. I'm tempted to conclude that convincing the powers that be to accept the solution would be easier than developing the propulsion tech that covers everything.

Edited March 29, 2016 by shynung

[Nibb31]

6 minutes ago, shynung said:

We have the solution that solves all the requirements above, except the last one. I'm tempted to conclude that convincing the powers that be to accept the solution would be easier than developing the propulsion tech that covers everything.

I think that you're wrong. Many people here seem to think that the hard part is figuring out the technological solutions to a problem. That is simply not true. The laws of economics and the laws of politics are just as real and just as immutable in the real world as the laws of physics. Stuff can only happen if the three converge. You might not like it, and I agree that it sucks, but it's the harsh reality.

Edited March 29, 2016 by Nibb31

[Basto]

I think the biggest barrier to interstellar travel is the fact that space is just really, really, REALLY big. 

A major limitation on human interstellar travel is the fact that humans don't do very well when subjected to high g forces for extended periods of time. Let's say 3g constant acceleration (probably optimistic) is our upper limit. It would take you nearly one year to accelerate to about 4.5% the speed of light. Let's say that's our upper limit of speed. Keeping in mind that you have to decelerate once you get to your destination that means a trip to Proxima Centauri would take about 100 years. And that's just the CLOSEST star. 

[shynung]

1 minute ago, Nibb31 said:

I think that you're wrong. Many people here seem to think that the hard part is figuring out the technology. That is simply not true. The laws of economics and the laws of politics are just as real and just as immutable in the real world as the laws of physics. Stuff can only happen if the three converge. You might not like it, and I agree that it sucks, but it's the harsh reality.

Actually, you've got it the other way around. I think we have the technology. NERVA, Orion, what have you. Research on them has gone pretty far, and the blueprints exists. A few decades of R&D, and we could have got the first prototypes flying.

What I think the problem is that nuclear-something is politically unacceptable for some reason. And I think it's easier to convince the public to accept these propulsion technologies, rather than inventing some other new technology to suit their whims.

[PB666]

38 minutes ago, Nibb31 said:

I think that you're wrong. Many people here seem to think that the hard part is figuring out the technological solutions to a problem. That is simply not true. The laws of economics and the laws of politics are just as real and just as immutable in the real world as the laws of physics. Stuff can only happen if the three converge. You might not like it, and I agree that it sucks, but it's the harsh reality.

Well if the propellant cost were cheap the political will would be much greater. The problem is that right now all propellant needs to be lifted off the ground and slung orbitally at 7800 meters per second.

dV = SQRT(2*orb. alt*g + u/r). Since even NASA is talking mars lander is a separate issue than the Mars flyby issue then I think we are talking about multiple missions for one Mars landing mission, we are talking lots of propellant.

Again NASA is underfunded, no doubt about that but if you are underfunded to you do one very expensive landing mission or some much cheaper robotized mission.

2 hours ago, shynung said:

I'll go right over your head, and bring you the Nuclear Salt Water Rocket

12.900 kN at 6.728 seconds, provides continuous thrust rather than Orion's pulses, and it works much like a hypergolic rocket.

Sure, the radiation's still a problem, but if designed correctly, this will get you anywhere fast.

you mean 6,728 seconds (ISPg) exhaust velocity of around 67000 m/s

[Nibb31]

2 hours ago, shynung said:

Actually, you've got it the other way around. I think we have the technology. NERVA, Orion, what have you. Research on them has gone pretty far, and the blueprints exists. A few decades of R&D, and we could have got the first prototypes flying.

What I think the problem is that nuclear-something is politically unacceptable for some reason. And I think it's easier to convince the public to accept these propulsion technologies, rather than inventing some other new technology to suit their whims.

My point was that convincing the public and the politicians is probably harder than solving the technological problems.

Besides, the problems with nuclear-powered rockets are not just "perceived". Nuclear power is relatively safe because there are extreme safety barriers and procedures in place, which makes it very expensive. Anyone who thinks that operating an Orion-drive spacecraft would actually be affordable is delusional. Building an infrastructure for building and handling thousands of nuclear bomb pellets is not going to be cheap, and the risk of proliferation cannot be underestimated. There is no way you can safely launch it from the ground (atmospheric explosions are not healthy, however you look at it, and you can't afford to irradiate a billion dollar launch site every time you launch a new one), so you would need literally hundreds of HLV launches to assemble the vehicle in orbit.

As for NERVA, yes, it was actually designed and tested, but it was eventually rejected for several reasons. It was supposed to be implemented as the S-N stage, to replace the S-IVB stage on a Saturn V. It would have offered twice the performance of the S-IVB, but for many times the cost. Not only was it politically unacceptable, it was also unnecessary and would have enormous costs to build new facilities and developing new procedures at the Cape for storing and handling nuclear fuel, alongside all the other highly hazardous material that is used there. Integrating a machine as complex as the Saturn V was one thing. Adding in the safety requirements for working on nuclear rockets makes everything orders of magnitude more complex.

This has all been discussed to death. The idea goes back to a day when the USAF was seriously discussing nuking the Moon, when Ford was going to put a nuclear family sedan on the market, and when the USSR was using nukes to dig artificial lakes. It was a crazy period, when plenty of great ideas made the covers of Popular Science, but luckily for us all, most of the crazy ideas of the 60's (not just the nuclear stuff) were rejected for very good economical and political reasons. With those roadblocks, the question of whether nuclear rockets are possible technologically or not is moot, because it's a non-starter however you look at it.

Edited March 29, 2016 by Nibb31

[Bill Phil]

5 hours ago, RenegadeRad said:

http://i.memeful.com/media/post/BRkm0vw_700wa_0.gif

See, that was what I was against in my post.

But, I have second thoughts after reading Shyung's reply... Btw Shyung wouldn't that take some serious g's and how will it "brake"

NSWR is worse than Orion. It's a continuous nuclear explosion. Or at least similar to it.

Orion is the best way we have currently to do anything other than chemical or ion.

6 hours ago, shynung said:

I'll go right over your head, and bring you the Nuclear Salt Water Rocket

12.900 kN at 6.728 seconds, provides continuous thrust rather than Orion's pulses, and it works much like a hypergolic rocket.

Sure, the radiation's still a problem, but if designed correctly, this will get you anywhere fast.

Oh I'm familiar. It's a bit more dangerous, though... At least in some ways. 

Orion would require development. As did the saturn V, the Atlas rocket, and a bunch of others. It all takes development. But we can do it. NSWR is still somewhat outside our reach, at least for now. 

The shock absorbers are more resilient than you think. They can easily take a hit from thousands of nukes. The problem isn't the nukes, it's when you don't take a hit from a nuke. That could cause the ship to rip apart. That's the most likely and most dangerous failure mode.

[fredinno]

5 hours ago, shynung said:

Solar panels doesn't work on all EM spectrums, as far as I knew, so painting them black wouldn't help. It'd just make the panels overheat faster.

Also, solar panels get less effective the farther the ship is from the sun. One would need a generator of some sort.

Soon, we will likely have solar panels that cover much more of the EM spectrum, like Infrared solar panels http://spectrum.ieee.org/energywise/energy/renewables/solar-cells-could-capture-infrared-rays-for-more-power

and UV panels https://en.wikipedia.org/wiki/Solar_cell_research#UV_solar_cells

[shynung]

@Nibb31

I like to think that operating an Orion-drive spacecraft as opposed to a chemical-powered spacecraft is like operating a freight train as opposed to a truck. Yes, it's theoretically more efficient and powerful, but aside from the enormous capital needed, things like radiation and fallout, Orion-proof infrastructure, among other problems, are something that has to be taken care of first. And I understand that it wouldn't be cheap; anything nuclear-related never was.

In the end, you have a point. Not exactly a good idea to potentially harm the biosphere by irradiating them every time we send a bird up there. Especially when the ones we sent up are only GEO satellites and space probes.

Maybe we'll find a use for these technologies once we found ourselves in need of transporting massive freight across the planets. Even then, I wouldn't be surprised if some other new propulsion tech got to it first.

Edited March 30, 2016 by shynung

[RenegadeRad]

This is getting interesting. We are now officially on the path where I wanted this conversation to go. Please continue.

@Shynung 

If solar panels would overheat, how about we add something in then which would convert the overheat, into energy?

Well that's ridiculous sorry but what if we try solar sailing? It seems potentially good.

@Nibb31 ayylmao I did say that I chose the word interstellar because it sounds cool you know not literally because I do know it is impossible too reach other stars with today's technology.

Another thing to add here that even if the mothership idea is useful and mainstream, why, just why (if we put aside funding, difficulty and economy) doesn't NASA or some countries get together and make this idea reality? You know how cool it will be. Like if we even have 2 of ISMs, major missions would be so easy, and still we try to add advances tech (nuclear pulse) in some 50s tech (the one vehicle to do it all rocket designs of appolo). Nonsensical. 

Oh and what's EM spectrum?

 

[Nibb31]

1 hour ago, RenegadeRad said:

 

@Nibb31 ayylmao I did say that I chose the word interstellar because it sounds cool you know not literally because I do know it is impossible too reach other stars with today's technology.

A debate is going nowhere if you insist on using words because they sound cool instead using the proper terminology. Do you want interstellar travel or interplanetary travel? Which is it ? Look them up if you don't know what they mean, and then we can talk.

Language is a communication protocol. Communication is only possible if we agree on using the same protocol, i.e. using the words that have the same meaning for everyone. If you don't agree on using the common protocol, we are not going to communicate.

Quote

Another thing to add here that even if the mothership idea is useful and mainstream, why, just why (if we put aside funding, difficulty and economy) doesn't NASA or some countries get together and make this idea reality? You know how cool it will be. Like if we even have 2 of ISMs, major missions would be so easy, and still we try to add advances tech (nuclear pulse) in some 50s tech (the one vehicle to do it all rocket designs of appolo). Nonsensical. 

But they are. The Apollo CSM was a "mothership" (It wasn't a "one vehicle to do it all", Apollo was distinctly a series of specialized vehicles for each job). The MTV in the Mars DRM (look it up please) concept is a "mothership".

This is another example where we are not communicating because you insist on using the wrong word "mothership" instead of something like "interplanetary transfer spacecraft". "Mothership" doesn't mean anything in engineering terms. A spacecraft is defined by its role.

I get it. You want something like the USS Enterprise, which could be loosely defined as a "reusable manned exploration vehicle". So why doesn't NASA build the USS Enterprise ? Simply because the technological level that would allow a warp drive powered reusable spaceship does not exist. We are stuck with expendable spacecraft, even for going to the Moon or to Mars, because we still haven't found anything better than chemical propulsion and because throwing away stages is much more efficient than carrying the penalty of reusability.

Besides, you are advocating using specialized vehicles (one for interplanetary transit, another for landing, etc...), which is pretty much mainstream since Apollo. Yet a multi-purpose exploration spacecraft actually goes against that idea. A spacecraft designed for visiting the asteroids would not have the same requirements as a vehicle designed for visiting Saturn's moons. Since the laws of physics reward staging architectures imply that you need an expendable design, it doesn't make sense to build a one-size-fits-all exploration vehicle.

So unless you come up with some technological breakthrough that enables us to build the USS Enterprise, we are stuck in reality. And trust me, when you have the brightest minds spending their careers at NASA, Boeing, Airbus, SpaceX, ESA, JAXA, CNES, Roskosmos, etc. all working on optimising spaceflights for decades, the answer is very unlikely to emerge from a kid on an internet forum.

Quote

Oh and what's EM spectrum?

Again, look it up. Google is your friend. Seriously, if you want to have a proper debate, you should have started there.

Edited March 30, 2016 by Nibb31

[RainDreamer]

Maybe a better concept for a "mothership" is similar to the one in the Homeworld game series, where it is more of a gigantic space factory that fly around. It is then capable of manufacture any spacecraft fitting mission requirement, given enough resources. It also have the advantage of being able to build and modify itself as needed. The problem is just we don't have the resources or technology to build something that scale in space yet. The best we can do is the ISS at football field size.

Edited March 30, 2016 by RainDreamer

[RenegadeRad]

@Nibb31 Thanks, I was not able to create a word so I took mothership and yes, I apologize for my communication. It's just about faster space travel, and "interplanetary transfer vehicle" is what that it is.

And lmao, where the hell are you going I am not talking about USs enterprise at all, you ok there?

[Nibb31]

28 minutes ago, RenegadeRad said:

@Nibb31And lmao, where the hell are you going I am not talking about USs enterprise at all, you ok there?

Hey, you're the one proposing a big "interstellar" reusable multi-purpose spaceship that runs on a magic propulsion system and carries a shuttle/lander craft. Whether you call it USS Enterprise, ISV Venture Star, Discovery, Endurance, or Battlestar Galactica, doesn't change the general concept. Neither of them are realistically possible in the foreseeable future.