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The weight figures for VASIMR do not include the cooling system for those superconductors;

Yes, they do.

Two spacecraft may be cheaper in the long run, and it can certainly be made to seem like a good idea with a great many assumptions. So far no one is putting their money down for it.

You mean like the non-nuclear tug that Lockheed Martin just proposed as their CRS-2 project?

Look, when you're in a hole, stop digging. You made fun of the concept of tugs in general as if the concept made no sense and as if the OP made up the concept. Don't be surprised that people are criticizing you for that.

For now, since the warp drive has a serious side effect ( 0.0 ). I rather put my money on the VASIMR prototype for now until "further research is done". Nasa has over 100 guys working on this project with AAR right now. So this one is very promising

Turns out I was wrong. I made myself sad. Here's the technology that might actually transform space flight.

http://www.adastrarocket.com/aarc/
http://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magnetoplasma_Rocket

The guy who invented it is an ex-Astronaut and VASIMR (or its tech underpinnings) was his PhD thesis at MIT for Applied Plasma Physics. I guess what I'm saying is he isn't a crank.

You pretty much nailed it all on the head. The only thing that I wanted to add was that there has been one probe to move between two massive bodies (Earth and the Moon) using a continuous thrust system: the SMART-1 probe with its Ion engine. The downside: it took 13 months (it only took the Apollo astronauts a couple days) and used a series of really strange, constantly expanding orbits (basically a spiral), on the plus side it only took 1/10th of the total propellant mass that a chemically powered spacecraft would.

Ion/Hall/Plasma thrusters are great for moving cargo where you don't care too much about how long it takes (especially in the beginning of the mission). This type of technology could easily be used to move fuel to one of these "Gas Stations" in earth, moon, sun, or mars orbit. You could start this years before the need date (before you get busy testing out the manned space craft) then the chemical fuel could already be there when you're ready to launch the manned space craft.

So, this coupled with a VASIMR (http://www.adastrarocket.com/VASIMR.html) engine will do wonders!

Actually, this was started as a private project. Dr. Chang Díaz has been working on some form of concept/design since his graduate school days at MIT in the late 70s. See the Ad Astra site. "Dr. Chang Díaz invented the VASIMR® concept and has been working on its development since 1979, starting at The Charles Stark Draper Laboratory in Cambridge Massachusetts and continuing at the MIT Plasma Fusion Center before moving the project to the Johnson Space Center in 1994. In the development of the VASIMR® engine, Ad Astra Rocket Company was teamed with NASA JSC, Oak Ridge National Laboratory, University of Texas at Austin, University of Houston and other various government space and research centers, industrial companies and academia including foreign universities." Ad Astra subsequently went private again on January 14th, 2005.

Also, correct me if I'm wrong, but ain't VASIMIR developed private company, not by NASA? Sure, NASA is working together with Ad Astra Rocket Company, but does NASA really deserve all the fame?

This started as a NASA project, at the Advanced Space Propulsion Laboratory at the Johnson Space Center.

Dr Franklin R. Chang Diaz (the other former astronaut involved, and not mantioned in this Canada-centric article) took the project to private industry in 2005

When I first saw this, I thought it was for powering VASIMR plasma engines.

Recently, AW&ST had an article suggesting that transit times between Mars and Earth 30 days could be possible using a continuously running VASIMR engine (it has an insanely high specific impulse). BUT, it would require a nuclear power source because the amount of solar panels (especially outside of earth's orbit) woudl be impractical.

myke

This was a full power test of the superconducting magnet and first stage only. The first stage is a 30kW ionization stage. The 170kW RF second stage has not yet been tested. Testing of the combined first and second stage will commence July 14th. From the manufacturer's site: http://www.adastrarocket.com/Release%20020709.pdf

check out http://www.adastrarocket.com/Jared_IEPC07.pdf

it's a paper that the researchers published last year describing what they had done with the previous version of the engine and what they planned on doing with this version

The new VX-200 (VASIMR Experimental, 200 kW) lab prototype we are working on has the capability of applying 200 kW of total RF power. ~30 kW to the first stage (Helicon plasma source), and ~ 170 kW to the second stage (Ion Cyclotron Heating, ICH, stage). The VX-200 will also have superconducting magnets (to be delivered in several weeks). The peak magnetic field inside the VX-200 will be on the order of two tesla, similar to the field strength in a strong MRI machine. At our old lab in NASA-JSC, we actually had a pacemaker safety line that limited people from getting too close to the intense magnetic field. Please see http://www.adastrarocket.com/vx200.html for a few more details.

The VASIMR engine that will be placed on the International Space Station (ISS) will likely be the VF-200 (VASIMR Flight, 200 kW). However, the flight version will actually have two 100 kW plasma cores. The two cores will have antiparallel magnetic fields, which sets up a quadrupole magnetic field configuration for the device as a whole. This quadrupole design is used so that the magnetic field dies off faster (1/r^4, instead of 1/r^3 as with a solenoidal magnetic field). In addition to being safer for the ISS, this faster die-off facilitates faster plasma detachment from the magnetic field lines of the nozzle. The ISS does not have 200 kW of power available for experiments, so a 200 kW battery pack would be charged up over a long period of time (hours to days) and used fire the VF-200 for a shorter period of time (seconds to minutes). Imagine looking up at the ISS flying by at night and seeing a bright blue and magenta kilometer-long plasma rocket plume.

Both the VX-200 and the VF-200 use argon gas as the propellant because of argon's mass and ionization potential. Previous VASIMR prototypes and experiments used hydrogen, deuterium, and neon. Argon is used for the current VASIMR prototypes because it will give an Isp of ~5000s (50,000 m/s). It turns out that this is an optimal Isp for the given LEO orbit, the cost of launching, and the power and weight of VASIMR and related components. A mars mission would likely use a lighter propellant like hydrogen because of the higher Isp obtained with lighter gases.

The reason that VASIMR 'wins' over other ion thrusters, ion engines, and Hall thrusters is that VASIMR can process a huge amount of power and couple that power into a neutral (equal number of ions and electrons) flowing plasma. In this way, VASIMR provides the exhaust velocity and fuel performance of an ion thruster, but produces 10 to 1000 times the thrust typically associated with these thrusters. VASIMR also has the ability to vary the power going to the first or second stage, thus changing from a high-thrust low-velocity exhaust to a lower-thrust higher-velocity exhaust, similar to shifting gears in a car while accelerating. The VX-200 is designed to produce upwards of 5 N of thrust.

The VASIMR program was moved out of the NASA-JSC Advanced Space Propulsion Laboratory in late 2007 and into the private lab of the Ad Astra Rocket Company in Webster TX (http://www.youtube.com/watch?v=ZXofYP_VfUg&feature=user

* A video from the NASA Advanced Space Propulsion Laboratory, the firing of the VX-100.
http://www.youtube.com/watch?v=KVsgSjm_vXg

* A video of the new VX-200 vacuum chamber arriving in Houston and being installed in the Ad Astra lab.
http://www.youtube.com/watch?v=yvg-Dsh9s2I&feature=user

* A video of a conceptual human Mars mission using 3 Megawatt-class VASIMR engines.
http://www.youtube.com/watch?v=Zj53rVWK5z0&feature=related

* Mike griffin makes a statement about placing VASIMR on ISS.
http://www.thespacereview.com/article/1182/1

Unlike a chemical rocket, a spacecraft using this engine would be able to get to orbit with some payload, and would not resemble "a disintegrating totem pole" getting there.

If by "get to orbit" you mean "take off from the ground and travel upward into orbit around the Earth," I don't think this engine is able to do that. Assuming this plot is correct, 10MW gives you 40 Newtons of thrust (less than 10 pounds) at maximum exhaust velocity. It's great for long trips (like to Mars) where you need as much impulse as possible for a given reaction mass, over a long period of time, but is completely useless for getting off the ground.

The manufacturer has this chart showing that it's a variable thrust rocket - hence the name: Variable Specific Impulse Magnetoplasma Rocket (Vasimir).

Unsaid is where the power comes from to drive the rocket. To get the kind of thrust they're looking for, it'll most likely be a descendant of Admiral Rickover's reactors we use in submarines because they're compact power sources.

Unfortunately, we're talking about NASA which means they're not really planning on doing anything. Per the article, Griffin wouldn't commit to when any testing was to take place just that someday maybe they might test a scale model. The project started in 1979 so it's an old project that looks to be a great idea that isn't moving very quickly. For those of you who weren't alive back then, 1979 was the year Three Mile Island happened. That accident, and the resulting hysteria, put the kabosh on everything nuclear in the US for the past 30 years.

Aside from the fact that the Variable Specific Impulse Magnetoplasma Rocket is designed for long-range spacecraft rather than satellites (and I think the difference is really only one of size) exactly how is it better/different? The VASIMR may actually be more versatile, and has quite a few advantages over standard ion designs (things like being completely electrodeless and containing its plasma propellent with EM fields so as to avoid corrosion). I'm all for improved rockets, and the general concept of the ion/plasma rocket is a good one, but it sounds like duplication of effort...