NEW PLASMA PROPULSION SYSTEM GENERATES A HELLUVA LOT OF THRUST

My understanding is that this (and related) drives tend to have slow acceleration, but are efficient in fuel capacity.

Thus they may be appropriate over very long distances, where speed may build over time. Then, there has to be space to slow back down again. Plus, once slowed there is still the issue of maneuvering at the destination, which usually requires greater accelerations.

I'm certainly not suggesting this is impossible, but there might need to be multiple types of engines if one type is based on nuclear power, such as emitting ions.

 

Woops - I didn't see that! Good points!

However, I think we're going to be using chemical propulsion for a long time.

That can be augmented by refueling, so that any single rocket launch doesn't have to lift the total fuel requirement for the mission.

I think a Falcon 9 can lift about 6 tons of cargo into transfer orbits used for missions beyond Earth when the Falcon 9 stages are flown to be reused.

That's been enough for what we have accomplished to date, I think.

A refueling solution could augment that by 6 more tons of nothing but fuel.

Refueling might be able to be done by the "supply" rocket attaching full fuel tanks to the "mission" rocket. Thus the payload for the "mission" rocket doesn't have to include space for empty tanks to be refueled in flight. Plus, we've gotten pretty good at docking maneuvers.

I think that's a tough package to beat by designing a whole new propulsion system for the various accelerations needed when visiting objects within Pluto's orbit and even beyond.

 

It's still redundant for propulsion; Have you ever heard of The Philadelphia Experiment?
Einstein's Unified Field Theory?
If we want to travel among the stars in our galaxy, little lone other galaxies, if we want to get galactic (or even our own solar system to get helium-3), you must 'bend' space, fold it, etc...
Plasma propulsion is barking up the wrong tree, though, plasma is great for reactor cores.
If I was to work with plasma, if it were me, and I have thought about focusing my energy into this or not; it would be on getting a plasma shield for a nuclear reactor to put into an aeroplane or drone and build it for the government to spy on shady regimes without ever having the need to come down type of stuff, ergo, nuclear powered flight. Just get a nuclear reactor light enough to drive a turbine and, Bob's your uncle.

I believe plasma's the key, as it's the heavy lead shielding that is holding us back from getting a nuclear reactor airborne without harming the occupants.

 

I think our military has this one under pretty darn good control.

We have drones that can stay at 60,000 feet for a day and a half.

We have satellites that have unbelievably great photographic capability.

 

And nuclear powered submarines that in theory only have to come up for food and water every 6 months.

The problem with doing that in the air is; the lead shielding is too heavy to get off the ground...

Now plasma shielding... That's how to get nuclear powered flights.

I'm not sure about plasma propulsion though; I mean, if we crack Einstien's Unified Field Theory, we can pretty much go wherever we want, from France to Betelgeuse, and beyond.

 

All these technologies have to have a serious justification - not just a possibility of creating it.

I haven't seen a justification for attempting nuclear powered aircraft.

There have been projects working on this idea, but the only ones I know about took place decades ago and were terminated.

I'm reasonably happy that we don't have plasma protected nuclear reactors flying overhead! Airplane emissions aren't insignificant, but ...

 

Satellites are in orbits.
Submarines have troubles coming inland.
Nuclear Aeroplanes; you get to be up there longer.

 

If speed is relative to distance, then why not change the distance.
Bend space time; unified field theory.

 

I know that sounds good.

There are scheduled nonsop flights from the USA to South Africa, Australia, and India, so range isn't the issue. My flight back from South Africa did have to refuel in the Azores, but I just don't see eliminating that stop as worth a lot of money. The flight back was something like 18 hours and I doubt the landing/fueling/takeoff cost more than an hour.

I take a reasonable number of flights (including 2020, when "reasonable" = 0). I've never wanted to be up there longer.

 

Yes, I have heard about all that stuff too, but, even though I'm a believer in those events, I don't think we have those technologies. At least, not in the open, yet.

Einstein never finished his work on the Unified Field Theory before he died. And, now we know about two more forces: Strong and Weak forces. So, he wouldn't have finished in his time anyway. And Gravity is still the odd one out.


By the way, why aren't you going into plasma physics if you really want to study it? Science needs more doers and dreamers.

 

So wrong I don't know where to begin, but that said;

1) The Philadelphia Experiment is a 950s UFO conspiracy theory and later a 1980s B Grade SF film (this is not science.) Also we don't have a Unified Field theory as yet - this would be science if it existed but it doesn't, here's hoping soon.

2) Electromagnetic shields has been explored both as of propulsion (EM sails) and as a means of shielding manned space craft from cosmic radiation (this is science).

3) Magnetic fields are central to reactor designs because they can be sued to contain charged particles that are released during fusion. They have not and are not being studied for use as shielding in fission reactors. This is because they will not stop neutrons (which have no electric charge) from escaping the fission core. And since you cannot have a fission reaction without neutrons you must have physical shielding instead, not necessarily lead (water works quite well) but shielding never-the-less because neutrons are harmful to human health. This is also science (think neutron bomb!).

4) The above means any spaceship relying solely on your 'plasma shields' to protect their crew from from radiation effects in space would, if the ship was built around a fission or fusion reactor be delivering a cargo of dead meat upon arrival at its destination. Unless of course you use proper shielding and separation (distance) to protect the crew. Science (again).

5) Neutrons are also produced by some but not all fusion reactions in significant amounts. This is a serious problem for current experimental Tokamak fusion reactors because the neutrons en-brittle the internal metallic surfaces of the reactor choice then fail. For this reason serious work is being done on coming up with alloys or other materials that are resistant to neutron embitterment problem. Also science.

6) There are types of fusion called aneutronic fusion which produce few or no neutrons (depending on the decay path followed by the products of the fusion reaction) that are being explored for exactly this reason. Also science again!

7) Plasma drives in numerous forms are being actively studied for rocket propulsion because they offer significantly higher ISP than chemical rockets. This means significantly higher velocities can be achieved for the same amount of fuel albeit the amount of thrust generated per second is less that that of a chemical rocket. VASIMR for instance talks about a 40 day transit time (for a fully developed system) as opposed to the 5-10 months! needed if you used a conventional rocket. And again (who knew)!

8 ) Plasma drives are a step on the road to true fusion drives which in theory could produce even higher ISPs and therefore allow even faster transit times. But they, unlike fusion rockets can be powered by any source or electric power including fission reactors. Fusion drives obviously require some kind of sustained fusion reaction - something we don't have and probably won't for some decades yet, at least in space.

And so you based on all of the above I'm afraid you are wrong plasma IS about propulsion . But yes, it's also about shielding and other useful stuff like decontamination, welding, communication and a whole range of other technologies ) .

 

Nuclear Reactors for use in Space, a current example (from Wikipedia);

 

Agreed!

Obviously, VASIMR is incredibly exciting, but my understanding is that it would require a power source that would provide far far more power than anything invisaged to be available for quite some time. That is, there is no such technology.

Like I said, it's still exciting and I hope work continues.

However, what we have today for exploration of the solar system is chemical rockets. That will get dumped immediately upon a better option and hope that happens. But, that doesn't look like it is going to happen in the predictable future.

 

Yep, the 'fully developed' version I mentioned in passing would require something like 3 or 4 hundred megawatts of power for that 40 day mission to Mars. The small test unit I pulled off wiki (which is tiny) generates something like 1 to 10 kilowatts.

Now there's technically not anything stopping you from building a 400 megawatts plant. The problem isn't output its mass, and cooling. You have to be able to lift your power plant into orbit before you can attach it to anything plus once it goes critical you have to get rid of all the waste heat it will produce which means massive (size wise) radiators. And we haven't got the tech yet to either launch one that size or cool it properly, even if we did have a design guaranteed to work seamlessly in zeo g.

So, small steps. We start with a few kilowatts of power and month long trips to Mars etc and build up from there.There are dozens of different plasma drive configurations to work with. One of my favorites is a microwave rocket that uses water as fuel. On paper it has twice the ISP of our best chemical rockets yet its basically just a souped up microwave oven. The tech is really well understood and basic and in theory you can stack them together in arrays to increase thrust - again once you have a power source big enough.

 

I'm glad there are people working on new propulsion systems.

I think the Mars trip time is really the least of the issues with travel time. It doesn't really block much of anything.

However, Voyager 2 took 12 years just to get to Neptune.

Travel times that high pretty much mean that those examining data from missions to outer planets are working with data gathered by technology of decades past.

The dragonfly helicopter to Titan won't launch until 2026 and won't arrive at Titan until 2034. High school students could have their physics phd's before that data is available. And the senior staff on this mission could be retired by then.

btw: Dragonfly is powered by a 70 watt MMRTG.

As per my previous comment on refueling, travel time could probably be reduced if our missions to outer planets could carry an additional 6 tons of rocket fuel.