NASA Plans Test of New Plasma Drive

Sallust writes "Flightglobal has an interesting article about the testing of a new electrically powered plasma engine called the Vasimir. It's being developed by former astronaut Franklin Chang-Diaz and promises to greatly reduce the time and fuel required for interplanetary journeys. According to the article: 'The Vasimir involves the injection of a gas such as hydrogen into an engine that turns it into a plasma. That plasma is then energised further using radio signals as it flows through the engine, a process controlled by electromagnetic waves from superconducting magnets. Accelerated and heated through this process the plasma is focused and directed as exhaust by a magnetic nozzle. Vasimir is many times more efficient than conventional chemical rockets and far less fuel is needed.' The developers are finalising an agreement with NASA to fit a scaled-down version of the engine to the ISS to conduct operational tests. There is also a concept video on YouTube suggesting a journey time for a manned craft to Mars on the order of 60-70 days."

Comments

Yes, attach it to the ISS

[BigDaddyOttawa]

What could possibly go wrong?

Re:Yes, attach it to the ISS

[oldspewey]

It's okay as long as they remember to leave the parking brake on.

Re:Yes, attach it to the ISS

[sharpmarble]

Attaching it to the ISS makes more sense than building another vehicle on-orbit to attach it to. They could rename the ISS the International Space Ship and send it to various vacation spots around the solar system.

Re:Yes, attach it to the ISS

[freddy_dreddy]

I think the point here is to exploit the recent discovery of water on Mars. With conventional fuels you have to take the return-charge with you. Concepts like these allow them to harvest Hydrogen on Mars for the return trip, which is pretty useful. The painful detail (apart from the complexity) is the mechanism for braking - you're f*d if that fails.

Re:Yes, attach it to the ISS

[Anonymous Coward]

Test with a prototype first.

Can you attach it to my car?

Re:Yes, attach it to the ISS

[Amouth]

actualy because this design heats the gas to a plasma state then uses EM waves to move it to create thrust - the idea could be used on just about any gas - your effeciency would be how much energy goes into heating it to a plasma state and keeping it there.

this is a great idea because they could design one engine and while the gas is consumed it could be replaced by any gas - and electricity is the true source of the power to run the engine..

we already know what gasses are readly avaliable on mars - design one to run on say H to get there (assume Hyrdogen is the easiset to heat to plasma sate) but have the engine also able to run on the gasses from Mars.. then when it gets there refill the tanks.. carge up the batteries (or use a nuke power source on the thing) and come on back - or keep going.

think of a ship with this type of drive.. then think about adding say a Bussard collector http://memory-alpha.org/en/wiki/Bussard_collector (i know we would have to invent a bussard collector but the idea is not that hard)

if this works they way the say it does - it is going to be one of the best propultion advances for traversing our solar system.

and with us having probes leaving our system - the data from there might show that there is a good ammount of particals in the space between systems.. if that is true then you could use this to send probes to other systems. sure it would take awhile but i bet they can alwasy make improvements.

Re:Yes, attach it to the ISS

[oldspewey]

Careful, you might end up buried partway in a cliff with a plasma drive hanging out your rear bumper.

Actually, the (supposedly) true story of the Rocket Car Legend is a rather interesting read.

Re:Yes, attach it to the ISS

[HydraSwitch]

This is exactly what crossed my mind too! :)

Whoops - we ran smack into planet earth.
Or the moon - take your pick.

Re:Yes, attach it to the ISS

[Omega996]

yeah, designing and building a bussard collector isn't that hard, it just needs something that can generate a magnetic field that doesn't diminish as the inverse square of the distance, since your magnetic or electrostatic funnel would have to be huge to pull in enough material to be worthwhile (even inside the heliopause). unless you're planning on not using a vehicle with any live crew or any sort of electronic equipment. I'm sure the difficulty of initiating and sustaining a proton-proton fusion to generate plasma is just a quick fix (no doubt you've already figured out the materials and fuel source for your carbon-nitrogen-oxygen fusion catalyser), as are the problems associated with getting the ramjet to speeds above the solar wind (unless the vehicle is making a quick one-way trip into the sun).

not much to do there, at all. You should get right on it, and we'll be heading toward Mt. Lookitthat within a few months. *rolleyes*

Re:Yes, attach it to the ISS

[Amouth]

rolleyes all you want// i wasn't suggesting something that was a perfect copy of sci-fi.. but what about something on the craft say like a normal funnle that can catch particals as it is moveing? sure your not going to get a 1 to 1 ratio of particals used to particals caught.. but you could least pas them through and help off set what is being consumed from onboard reserves.

i was just suggesting something that could pick up gasses pressent in the path of the probe.. assume for a min that you do get out of the solar system.. and there is an intersteller wind.. why not point the collector at it and get particals and store them untill you have enough to move on? sure the wind will move you but hopefuly you could maintain your place well enough to gain particals to push away with..

think of it more how a jet engine works instead of a ram jet.. the jet engine takes in air and compresses it then combines fule and ignites it and trust is produced..

you could move forward collecting particals in an "intake/bussard collector fashion" then compress them and heat them to plasma state (same as injecting fule into air) then use em waves to push them away (same as ignighting them) and provide thrust..

the whole idea is that you wouldnt' have to put all the particals you will need for a trip from earth to nearest system on it to start with.. but rather a good amount and get the rest of them as you go along..

again - roll your eyes all you want and say that nothing is possiable without making a groud breaking discovery.. but i am sure plenty of people told these people the same thing when they came up with the idea to start with.

Re:Yes, attach it to the ISS

[Omega996]

flamebait? fuck off, you ingnorant moderators.

as for amouth - you really seem to have no idea how tenuous the intersteller medium (or solar wind, for that matter) is. at one astronomical unit, there are only about 7 protons per cubic centimeter. The further one goes from the sun, the more tenuous the solar wind gets. by the time you've passed the heliopause, the particle density is roughly one per cubic centimeter. Since even at earth distances the solar wind is so thin, your 'jet intake' (the actual collection radius of your "scoop) will have to be several hundred kilometers wide to bring in enough fuel to be useful. There is drag involved with such a scoop - both from the particles entering the scoop, as well as drag from the galactic magnetic field. You still have to provide power for the magnetic field, and if you're not fusing the material from the solar wind, you have to provide power to run your microwave heater to turn the fuel into plasma. there isn't enough material in between planets (or stars, for that matter) to be used as fuel for anything less than a technology-as-magic level.

Re:Yes, attach it to the ISS

[Omega996]

damn, ignorant with a typo - ah, well...

Re:Yes, attach it to the ISS

[isomeme]

What do you mean by "braking"? In space, braking is just accelerating in a different direction; depending on your frame of reference, the same acceleration might be increasing or decreasing the magnitude of your velocity vector.

If you mean that the problem is landing on Mars and later getting back into space, then you're correct. Low-thrust drives are perfect for long trips around the solar system, but useless for getting from orbit to planetary surfaces and back again.

Re:Yes, attach it to the ISS

[nacnud75]

The Environmental Control and Life Support System (ECLSS) planned for the ISS will use recycled water and split it into Oxygen and Hydrogen. The Oxygen is used to support the crew while the hydrogen is dumped. A VASIMR might be able to use this hydrogen to reboost the station, reducing the need for ISS resupply with toxic propellants.

Re:Yes, attach it to the ISS

[CodeBuster]

Yes, but when it reaches Alpha Centauri who will get credit for "wining" this round of Civilization?

Re:Yes, attach it to the ISS

[Plutonite]

Nothing, other than the toilet crashing again. But I understand that is a major issue for you mortals.

PS: do deities pee? Yes this is as offtopic as it gets, but you have to admit it's an interesting question. I'm sure some of them do, right?

Re:Yes, attach it to the ISS

[Anonymous Coward]

haha omega flamebaiter

Re:Yes, attach it to the ISS

[Lars T.]

then think about adding say a Bussard collector http://memory-alpha.org/en/wiki/Bussard_collector (i know we would have to invent a bussard collector but the idea is not that hard)

And I thought Robert W. Bussard already took care of that.

Re:Yes, attach it to the ISS

[Anonymous Coward]

Uh, wouldn't you STILL need rockets to escape any gravitational force? AFAIK, these plasma engines are only good for slow non-gravitational acceleration, not achieving orbits. T

Re:Yes, attach it to the ISS

[marco.antonio.costa]

Heh, the mechanism for braking is turning the ship 180 degrees as you reach the middle of the trip. But basically having the propulsion system go dead spells death of everybody no matter what system you use.

And since hydrogen is the most abundant element in the universe, I'd reckon the design decision to use it pretty good.

We just need compact and efficient nuclear reactors for the power, for a ship I mean, solar panels might be just fine for the ISS.

Re:Yes, attach it to the ISS

[markass530]

did you really link to something off of star trek or some shit as a point of reference??????????

Re:Yes, attach it to the ISS

[Fulcrum of Evil]

A gadget isn't properly invented until you build one. Asimov conceived satellites, but the soviets invented it.

Re:Yes, attach it to the ISS

[Anonymous Coward]

you could use this to send probes to other systems. sure it would take awhile but i bet they can alwasy make improvements.

A while? It would take like several thousand years. Talk about long-term investment.

Perhaps the probe could return interesting observations from its interstellar trip by radio until it arrives at its destination system, though.

I'm no astronomer, but I would guess that the further away you get from a star, the more of the deep space becomes observable. Just leaving the solar system should bring back interesting data and from then on it would just keep getting better - for thousands of years. Changing civilizations would have to pickup and analyze the radio data from the probe.

Interesting.

Re:Yes, attach it to the ISS

[tenco]

http://memory-alpha.org/en/wiki/Bussard_collector

Argh. Bussard ramjet. You always link to Star Trek to "explain" something?

Re:Yes, attach it to the ISS

[VoidCrow]

Isn't it inverse cube? YOu'd need a monopole to get inverse square, or a very long, thin, dipole.

Re:Yes, attach it to the ISS

[RockDoctor]

The painful detail (apart from the complexity) is the mechanism for braking - you're f*d if that fails.

The braking mechanism for a reaction drive ? Well, pending some "New Physics" based on the crystalline excretions of a wombat's anal gland, I think that we'd have to use Newton's Third Law ("for every action there is an equal and opposite reaction" ; it's what puts the "reaction" into the "reaction drive"). To brake, you use the reaction drive. That's why the mid-point of long trips in a reaction-drive vehicle is called "turn over".
Of course, you don't rely on one reaction drive ; you use multiple fuel tanks manifolded to multiple reaction drives and you have significant redundancy in the turn over mechanisms too (say, gyroscopes AND attitude jets). But that's just conservative engineering.

Oh, were you joking?

Re:Yes, attach it to the ISS

[albyrne5]

I don't get the ""wining"" bit?

Re:Yes, attach it to the ISS

[Amouth]

yes i did for the concept idea - something that gathers particals from what is avaliable in interteller space..

while there is no existing device that does this.. i could spend 5min explaining the idea or refrence a concept from sci-fi that every damn person here knows about.

i did no refrence it as fact "hey lets put this sci-fi thing on it and send it away" but hey how is that "comunitcator" in your pocket doing?

Re:Yes, attach it to the ISS

[Lars T.]

A gadget isn't properly invented until you build one. Asimov conceived satellites, but the soviets invented it.

So much for all the talk of "prior art" on Slashdot.

Re:Yes, attach it to the ISS

[CodeBuster]

It was a dig on the notion that civilization is a game which can be won and the irreverent style of the series and especially the more recent installments, Civilization IV for example, which poke at themselves in a self deprecating sort of way. Some people, upon whom the humorous factor is lost, have even complained that the games present a decidedly western and essentially Americanized manifest destiny view of world history where capitalist democracy combined with a powerful military is the supreme level of achievement for any civilization without realizing that part of the game is ridiculous situations which are funny precisely because they are absurd. So there you are, some background on the inside, or should I say outside now, joke.

Re:Yes, attach it to the ISS

[steve_bryan]

I realize this thread has devolved to being just about interplanetary and interstellar flight segments but it is still worth noting that getting to Mars is not good enough. You need to drop into and climb out of a fairly daunting gravity well. Refueling your plasma engine won't be sufficient for a return trip to Earth. You need chemical engines with their thrust characteristics to land and take off from Mars.

Costs rise precipitously if you have to carry all you chemical fuel during your initial launch. To overcome that hurdle you need something like Zubrin's plan for manufacturing chemical rocket fuel on Mars. On the other hand the plasma engine concept appears very appealing for travel between Earth orbit and Mars orbit. Maybe we could even build the first space elevator on Mars to finesse the Mars gravity well issue eventually.

Re:Yes, attach it to the ISS

[Omega996]

inverse square near the craft, inverse cube at distance, i thought. probably not an issue, anyway - if the craft needed to burn 1 gram of hydrogen per second, and the average particle density is 7 per cubic centimeter, the funnel would have to be stupidly big to capture enough hydrogen to feed it.

Re:Yes, attach it to the ISS

[Anonymous Coward]

And so the wine was for the victory celebration?

For me, wining is for dining.

Re:Yes, attach it to the ISS

[VoidCrow]

That's true, and a 'practical' bussard ramjet would probably have to be long and thin to stretch out the square to cube transition. There would be a time dilatioon effect in raising the apparent hydrogen density at higher velocities, though.

Makes me happy

[SSIlver2002]

It's stuff like this that makes me happy and brings a huge smile to my face. It also makes my imagination go wild! I hope something like this gets implemented sooner than later.

Re:Makes me happy

[Anonymous Coward]

Warp 9, Lt.!

plasma exit velocity?

[oldspewey]

Neither summary nor TFA give any indication of the velocity of plasma exiting the engine. How does it compare with chemical rocket? Ion drive?

Re:plasma exit velocity?

[Intron]

We can guess that it is similar to the DS-1 Ion drive which propels Xenon ions at 30 km/sec.

Re:plasma exit velocity?

[wurp]

This sounds a lot to me like it *is* an ion drive. I didn't RTFA, but a plasma is characterized by a separation of the electrons from the nuclei. The only difference between that and an ion drive is that not necessarily all electrons are stripped from the atom in an ion drive.

I don't know how (or if) you would distinguish between ionic hydrogen and a hydrogen plasma (hydrogen atoms have only one electron...)

In both cases you give the propellant momentum with either electric or electromagnetic force, and both are much more efficient than chemical rockets. I would also expect both to have miniscule thrust compared to chemical rockets, and hence only be appropriate for navigation when you already have orbital or superorbital velocities.

Re:plasma exit velocity?

[DarthVain]

More importantly how does it compare to twin ion engines? The empire wants to know!

QIE - Quad Ion Engines, now with the added benefit that they don't look like bowties. Under utilized as the name isn't very catchy...

Re:plasma exit velocity?

[bodino]

Wiki - the source of all knowledge - has some good details.

http://en.wikipedia.org/wiki/Variable_specific_impulse_magnetoplasma_rocket

Re:plasma exit velocity?

[avandesande]

radio heating scales (up) much more easily than ION thrusters.
Google 'microwave plasma balls' and you will get the idea.

Re:plasma exit velocity?

[dhartshorn]

Wikipedia is your friend.

http://en.wikipedia.org/wiki/Variable_specific_impulse_magnetoplasma_rocket

Re:plasma exit velocity?

[AKAImBatman]

VASIMR (Variable Specific Impulse Magnetoplasma Rocket) is a variation on the Magnetoplasmadynamic thruster (MPDT) that has been in development for a decade or two. These thrusters are coveted for their rare combination of high specific impulse (i.e. efficiency) and thrust to weight ratio (power). Such a combination makes them ideal for manned missions, as they allow space craft to fly under constant, high powered thrust. This is the "holy grail" of space travel because it cuts down the TIME in flight significantly. Thus the summary's mention of a 90 day flight time to Mars. (Normal flight time using a minimal Hohmann Transfer is ~1.5 years.)

Obviously, the exact thrust numbers depend upon the rocket. However, the VASIMR rockets have a range of specific impulses from 3,000 to 30,000 seconds. You can see how that compares to Ion Thrusters here. Chemical rockets tend to top out at 500 seconds and thus don't even place when compared to VASIMR or Ion thrusters. The only reason why we want to keep using chemical rockets once we have better thruster technology is that all these new technologies lack the thrust to weight ratio to get a rocket off the ground. i.e. They are only good for space travel. Atmospheric flight need not apply.

Re:plasma exit velocity?

[HRogge]

Ion drives use electromagnetic fields to accelerate particles with an accelerator. Most times they use heavy atoms like xenon.

VASIMIR makes plasma from light elements like hydrogen and then use electromagnetic fields to heat the plasma... by controlling the temperature you can change the thrust/momentum the engine creates.
(at least that's what I heared).

Re:plasma exit velocity?

[avandesande]

From wiki:

Current VASIMR designs should be capable of producing specific impulses ranging from 3,000 to 30,000 seconds (jet velocities 30 to 300 km/s). The low end of this range is comparable to some ion thruster designs. By adjusting the manner of plasma production and plasma heating, a VASIMR can control the specific impulse and thrust. VASIMR is also capable of processing much higher power levels (megawatts) than existing ion thruster electric propulsion designs. Therefore it can provide orders of magnitude higher thrust, provided a suitable power source can be provided.

Re:plasma exit velocity?

[Dancindan84]

Google 'microwave plasma balls' and you will get the idea.

I'm completely in awe that I didn't get a single porn site on the front page doing that search.

Re:plasma exit velocity?

[seanonymous]

So, how many of these would be needed to equal the force of a small atomic bomb? Could this be a more fuel efficient way to nuke things from orbit?

I mean, I don't want to harm the environment any more than I have to, but some times, you just have to be sure about something.

Re:plasma exit velocity?

[quercus.aeternam]

The key to remember is that the exit velocity is *variable*. Wikipedia suggests that jet velocities can be anywhere from 30 to 300 km/s.

http://en.wikipedia.org/wiki/Variable_specific_impulse_magnetoplasma_rocket

Re:plasma exit velocity?

[wurp]

Well, actually I *do* know the difference between ionized hydrogen and hydrogen plasma - hydrogen plasma may have all the electrons present, they just won't "stick" too the atoms because they're too energetic (i.e. hot).

By definition, atoms in a plasma have lost their electrons due to temperature.

I really just wanted to point out that they're very similar. I'm sure HRogge is right regarding the differences.

Re:plasma exit velocity?

[jmichaelg]

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.

Re:plasma exit velocity?

[rk]

(Normal flight time using a minimal Hohmann Transfer is ~1.5 years.)

I think you forgot to divide by two. The duration of the whole Hohmann Earth/Mars transfer orbit is about this long, but you only use half of it to get there.

Re:plasma exit velocity?

[Intron]

Let's see, a kiloton of TNT = 4 x 10^12 joules all released in a fraction of a second.

A megawatt of power for 30,000 seconds (8 hours) = 3 x 10^10 joules, so no nuking here.

Also, unless I misunderstand this, you don't get more energy as thrust than you can put in as electricity. So to get that megawatt of power out, you need a megawatt of electricity in. Solar panels will only get you 1300 W / m^2 with 100% efficiency at the Earth's orbit. I guess you need a really long extension cord.

Re:plasma exit velocity?

[AKAImBatman]

Good catch. So 8.5 months for a one-way trip vs. 3 months. I'll take the VASIMR any day of the week. :-)

Re:plasma exit velocity?

[Profane MuthaFucka]

A more fuel efficient way to nuke things from orbit is to haul the nuke to the target in a wagon pulled by a horse.

I think you're mixing up specific impulse with thrust.

Re:plasma exit velocity?

[Anonymous Coward]

The VASIMIR isn't new... it was developed by NASA over 10 years ago, but the power-thrust/mass ratio didn't justify funding it. It just sounds like someone who wouldn't let it die. You're right, this is an ion drive with the difference that the net fuel charge is zero, as opposed to a true ion drive which ionizes a neutral fuel (usually a noble gas like Xe or Ar) and uses the excess charge repulsion to generate thrust. This disassociates neutral hydrogen using RF coils, so no charge is introduced, but the reactive plasma is used to generate an Isp. The plasma propulsion effect is much more charge than heat. Your goal is to minimize heat release. Thermal expansion on sparse plasmas in deep space doesn't generate much thrust (we're talking PV cooling), it just causes a cooling problem, trying to keep the propulsion system properly controlled (thermally).

Re:plasma exit velocity?

[Anonymous Coward]

That's silly. The new buzzword is 'dual'. Imagine it: Dual Ion Engines - DIE for short. I think it has potential...

Re:plasma exit velocity?

[BazilBBrush]

OOOOOOh! Plasma, so exotic...

I wonder what the dead pixel return policy is???

Re:plasma exit velocity?

[Anonymous Coward]

Depends on the taycheon field emissions.

Re:plasma exit velocity?

[Anonymous Coward]

Exotic states of matter get me all... moist.

Re:plasma exit velocity?

[Omega996]

an ion drive takes atoms of an element and strips off some of the electrons in order to make the particle charged (ions). These charged particles are then directed through an aperture with an opposing charge, accelerating them. When an ion with a positive charge comes in contact with a free electron, it captures it, and the atom reverts back to a charge-neutral state.

a plasma is a gas that is energetic enough that the positively-charged nuclei and negatively-charged electrons circulate in a gas. As long as the energy levels are high enough, the nuclei will not capture the free electrons. the amount of charge carried in a plasma is a function of the ratio of ions and electrons versus neutral particles in the gas.

Re:plasma exit velocity?

[mi]

However, the VASIMR rockets have a range of specific impulses from 3,000 to 30,000 seconds.

This is the part I don't get, but you probably do. Why would I lower the exhaust speed, instead of lowering the mass?

The distances a spacecraft can travel in a given time are limited by the mass of "stuff" it can throw back multiplied by the speed, with which it is thrown. So, one would think, the most efficient engine would be throw "stuff" out as fast as it can, and if lower thrust is desired at times, it would throw less of it instead of throwing the same amounts at lower speed...

Or is varying the amount at will simply too difficult today and requires another 10 years of research?

Re:plasma exit velocity?

[Agent__Smith]

More importantly how does it compare to twin ion engines? The empire wants to know!

QIE - Quad Ion Engines, now with the added benefit that they don't look like bowties. Under utilized as the name isn't very catchy...

I want to know how it compares to a Saturn ion...

Re:plasma exit velocity?

[Danny Rathjens]

http://en.wikipedia.org/wiki/Spacecraft_propulsion#Table_of_methods_and_their_specific_impulse

Re:plasma exit velocity?

[Phil Karn]

I assume you meant "power in the exhaust", not "energy as thrust"?

Re:plasma exit velocity?

[GleeBot]

Actually, the main reason to have a variable Isp (specific impulse) engine is because there's a direct trade-off between Isp, and energy.

Note that momentum transfer increases linearly with velocity and mass, but kinetic energy increases linearly with mass and with the square of velocity. Thus, to make a given amount of mass go faster requires a lot more energy.

A more concrete example: You want to impart a total impulse of 2MV. You can either get it throwing out a mass M at 2V (mass efficient), or by throwing out a mass 2M at V (energy efficient).

In the first case, you use 1/2 M (2V)^2 = 1/2 M 4V^2 = 2MV^2 energy, while in the second case, you use 1/2 2M V^2 = MV^2 energy, or half as much, for the same total impulse. This only gets worse the bigger the velocity difference gets.

Often, the limiting factor in electric propulsion technologies like these is the power supply, not the thruster. Generally, to get the max Isp all the time you'd need a power supply so massive (like a nuclear reactor) as to completely throw off the mass fraction.

So generally, the way these systems are proposed to be operated is with a fixed power budget, and switched between mass efficient, low thrust mode (for long term delta-V), and mass inefficient, high thrust mode (for certain maneuvers).

Re:plasma exit velocity?

[marco.antonio.costa]

In most ion drives there is interactions between the electrodes and the propellant, reducing reliability and maximum input too, I believe.

In the VASIMR the electrodes and propellant are completely separate by the containing magnetic field, which also means that the temperature of the plasma, thus propellant speed, is only limited by the power used to heat it, up to fusion temperatures, which is hellishly cool.

This gets my geek insticts completely haywire, sorry for the fanboyish post. :P

Re:plasma exit velocity?

[Anonymous Coward]

How about Triple Ion Engine (TIE) Fighter? Catchier?

Re:plasma exit velocity?

[from_downunder]

Thats because you had google safe-search running

Re:plasma exit velocity?

[Hal_Porter]

The Goauld in SG1 would never have made a rookie mistake. They had Deathgliders. DEATHGliders. You'd think the Empire would have picked up on the DIE Fighter idea, once some business consultants had told them their core business was intimidation.

Re:plasma exit velocity?

[phaunt]

Wiki - the source of all knowledge - has some good details.

The source of all knowledge is exactly what it isn't. It's (or should be, at least) an aggregation of information from reliable sources.

Re:plasma exit velocity?

[Coraon]

wait? something that violates rule #34?! That's something truly news worthy.

Nice to see fact moving faster than fiction

[CRCulver]

Who knows if this thing will work out, but it would be amusing if it did. In histrilogy beginning with Red Mars , Kim Stanley Robinson had interplanetary journeys being trimmed down to such short lengths only a couple of hundred years from now, and KSR's work tried hard to be scientifically plausible.

Re:Nice to see fact moving faster than fiction

[spun]

Fact is often capable of moving faster than fiction, it just takes a collective decision to make it so. We could have been to Mars already, just like we could be feeding everyone in the world. We just don't care enough.

Re:Nice to see fact moving faster than fiction

[molo]

Yeah, but in the series, transport power was based on cheap cold fusion of water. They would accelerate a craft at 1g towards the target, drift for a time in the middle, and then turn around and decelerate at 1g for roughly the same time. It provided transport between Mars and Earth orbits on the scale of a week (depending on their relative positions).

Then the slow part of the journey was considered to be the time spent ascending and descending the space elevators to reach the planet's surface from orbit. It would take almost as long as the interplanetary trip between Earth and Mars.

-molo

Re:Nice to see fact moving faster than fiction

[downhole]

And as I recall, the engine design in the book was based on using a laser to start a fusion reaction in pellets of fuel, and somehow directing the resulting energy output along an axis to provide thrust. Sounds cool, but I would expect we'd figure out how to get electricity out of a fusion reaction first.

Re:Nice to see fact moving faster than fiction

[clonan]

pB11 in a Bussard Polywell!!

We should hear something in the next month!

Re:Nice to see fact moving faster than fiction

[frenchgates]

I frequently see in slashdot replies that this or that could happen if enough folks decide to do it. People say things like "feeding the world is a political problem, not a resource problem." The problem is that political will and the ability to manipulate it are kind of like limitations based on laws of physics. Sure in theory we could steer the earth if we all jumped up and down at the right time. It just isn't possible to convince everyone to play.

Re:Nice to see fact moving faster than fiction

[rubenerd]

You're absolutely right. Collective will of corporations, governments and people (land, labour, capital and enterprise for those economically inclined) towards a single goal in the past has resulted in amazing things being achieved. Alas it's just too uncommon for all three groups to be interested in the same things at the same time, because they have different priorities and perceived needs.

What I'm hoping for now is that with the shrinking of the world there is a huge opportunity for corporations, governments and people to work together regardless of their geographic location quite unlike any other period in our collective history.

Optimistically, together we can achieve so much. Realistically, I think we're still more interested in spending our land, labour, capital and enterprise resources on killing each other over differences such as religion, resource allocation and political ideology.

As a terribly politically incorrect end note though, the jet turbine engine was created as a direct result of war. Who knows, a new cold war may have people racing to other planets, comets or solar systems instead of our moon. It's interesting to think about: how much of our progress is just making sure someone else doesn't do it first?

Re:Nice to see fact moving faster than fiction

[Anonymous Coward]

Iraq though, we care about.

Re:Nice to see fact moving faster than fiction

[Hal_Porter]

I frequently see in slashdot replies that this or that could happen if enough folks decide to do it. People say things like "feeding the world is a political problem, not a resource problem." The problem is that political will and the ability to manipulate it are kind of like limitations based on laws of physics. Sure in theory we could steer the earth if we all jumped up and down at the right time. It just isn't possible to convince everyone to play.

Global fascism could solve that problem.

Re:Nice to see fact moving faster than fiction

[Hal_Porter]

Project Daedalus used fussion pellets

http://en.wikipedia.org/wiki/Project_Daedalus

Daedalus would be constructed in Earth orbit and have an initial mass of 54,000 metric tons, including 50,000 tons of fuel and 500 tons of scientific payload. Daedalus was to be a two-stage spacecraft. The first stage would operate for two years, taking the spacecraft to 7.1% of light speed (0.071 c), and then after it was jettisoned the second stage would fire for 1.8 years, bringing the spacecraft up to about 12% of light speed (0.12 c) before being shut down for a 46-year cruise period. Due to the extreme temperature range of operation required (from near absolute zero to 1,600 C) the engine bells and support structure would be made of beryllium, which retains strength even at cryogenic temperatures.

This velocity was well beyond the capabilities of chemical rockets. Instead, Daedalus would be propelled by a fusion rocket using pellets of deuterium/helium-3 mix that would be ignited in the reaction chamber by inertial confinement using electron beams. 250 pellets would be detonated per second, and the resulting plasma would be directed by a magnetic nozzle. Due to the scarcity of helium-3 it was to be mined from the atmosphere of Jupiter via large hot-air balloon supported robotic factories over a 20 year period.

I'm not sure if the inertial fusion system would be possible to build. Mind you if you could, you could mine the He3 off the moon without needing to go to Jupiter.

Re:Nice to see fact moving faster than fiction

[VoidCrow]

> Sure in theory we could steer the earth if we all jumped up and down at the right time.

Actually we couldn't. That *is* a limitation based on the law of physics, unless you can train people via corporate motivational techniques to exceed escape velocity with each jump.

Re:Nice to see fact moving faster than fiction

[spun]

You might like to read And Having Writ, a sci-fi book about aliens crash landing at Tunguska and attempting to jump start our technology by getting us into a world war. It's quite funny.

All they have to do now...

[fiannaFailMan]

...is optimize the plasma conduits, although they'd better make sure not to divert too much power away from the main deflector array, I'd hate to have to reconfigure that thing yet again.

Re:All they have to do now...

[fm6]

It took longer for somebody come up with a Star Trek tie-in than I thought. Are we finally tired of that particular franchise?

As I recall, the plasma conduits on Star Trek were always blowing up. Very convenient for the writers in case they need to stage a tragic death on the bridge, though it seems strange that they'd route such a dangerous device into an area populated by so many key people. In any case, plasma is obviously dangerous and unreliable, and I wonder at NASA using it!

Re:All they have to do now...

[FauxPasIII]

> though it seems strange that they'd route such a dangerous device into an area populated by so many key people

The EPS (electrified plasma system) is basically the power grid of a starship, it has to go anywhere that needs electricity.

http://memory-alpha.org/en/wiki/EPS

Re:All they have to do now...

[Anonymous Coward]

Off topic but do you think we (that is, regular and mostly untrained civilians) should really be allowed to carry guns on commercial flights?

Re:All they have to do now...

[fm6]

And this is superior to simple (relatively non-lethal) copper wires because...?

Re:All they have to do now...

[lgw]

You can only put so much current through a busbar. What do you do when a solid copper bar 4 inches across won't carry the power you need? Eventually the size and mass of the busbar required make scaling up in power impractical. For drives, weapons, computer cores, and the like it makes sense.

Of course, that doesn't explain why the bridge consoles exploded regularly - that's just lowest-bidder construction.

Re:All they have to do now...

[Anonymous Coward]

Plasma Conduit = High current, high temperature superconductor. Necessary when you're routing Gigawatts (at least) of power around a ship.

Re:All they have to do now...

[SlowMovingTarget]

I can think of a number of reasons:

1. It's harder to run out of magnetic fields than it is to run out of copper.
2. Exploding Plasma is way cooler than non-exploding copper. I suppose you could make copper plasma, but see number 1.
3. The old Constitution class used copper wiring, but the space rats and non-corporeal vampiric fart-wraiths kept chewing through it (begin dramatic STOS music). With plasma conduits, the whole ship is one big giant bug zapper.
4. EPS conduits can also predict pregnancy when you pee on them. I'd like to see your copper wire do that!

Re:All they have to do now...

[fm6]

Except that the bridge doesn't have (or shouldn't have) high-energy devices, it has controls for high-energy devices. When you have dangerous devices that tend to explode, you don't put your desk right next to the device, you put it somewhere a safe distance away and operate the device by remote control.

As for low-bidder construction, I seem to recall that the Federation has banished greed and competition. But I suppose that's just government propaganda.

Re:All they have to do now...

[fm6]

It's harder to run out of magnetic fields than it is to run out of copper.

So Star Fleet puts all its people at risk to save money? Does Federation OSHA know about this?

Exploding Plasma is way cooler than non-exploding copper. I suppose you could make copper plasma, but see number 1.

Which speaks to the number one principle of TV/Movie SF: Whiz-bang is more important than logic.

Except that TOS developed its following by having exactly the opposite priority. The inability of TNG to make that same priority work tells me that Roddenberry actually contributed little to TOS. Then after he died, they gave up on it altogether and went to the old standby of Blowing Things Up.

The old Constitution class used copper wiring, but the space rats and non-corporeal vampiric fart-wraiths kept chewing through it (begin dramatic STOS music). With plasma conduits, the whole ship is one big giant bug zapper.

I don't remember the episode with no-corporeal vampiric fart-wraiths. Was that the episode with the Girl from the Green Dimension? No wait, that was Lost In Space, never mind.

EPS conduits can also predict pregnancy when you pee on them. I'd like to see your copper wire do that!

I think I speak for fans everywhere when I say: EWWWWW!

Re:All they have to do now...

[SlowMovingTarget]

I don't remember the episode with non-corporeal vampiric fart-wraiths.

Just as the Klingons don't talk about the period in their history when they lost their cranial ridges and became "hooligans," the Federation finds their run-in with non-corporeal vampiric fart-wraiths deeply embarrassing. From now on, though, you'll know what those crew members are talking about when they claim the helmsman just ran over a frog.

Re:All they have to do now...

[lgw]

I had a car once with an ammeter. Now this is a great gauge to have because it's the only thing that will tell you that your alternator is bad before you get stranded somewhere, but *all* of the current has to flow through the ammeter. You'd think there'd be a sensor next to the alternator, and just a display in the dash, right? Nope, *all* the current in the car went into the dash, through the ammeter there, and back through the firewall to the engine/headlights.

All I could think of when I discovered this was "these guys watch too much Star Trek". The car was a 69 or 70 model, so maybe they did!

Re:All they have to do now...

[Tom9729]

Perhaps the Federation has been outsourcing ship construction to Ferenginar?

Re:All they have to do now...

[fm6]

That would explain it. Probably after the hotly contested election to the Federation High Council of Dubya from the Shrub Planet and his evil minion, The Chaney.

Re:All they have to do now...

[Hal_Porter]

As for low-bidder construction, I seem to recall that the Federation has banished greed and competition. But I suppose that's just government propaganda.

They've eliminated money too. If people complain to the the LCARS guys that consoles sometimes explode and kill their users, they will be told that "patches are welcome", or asked to contact the Ferengi who made the hardware and get them to release specifications rather than just binary drivers for Klingon operating systems.

Re:All they have to do now...

[FauxPasIII]

# EPS conduits can also predict pregnancy when you pee on them. I'd like to see your copper wire do that!

I think you're confusing it with the primary EPT manifold.

Or with inverse tachyons. Those little fuckers can detect anything.

cool

[ionix5891]

all is left now is for someone to come up with a warp drive :p

Re:cool

[Trent Hawkins]

all is left now is for someone to come up with a warp drive :p

Nah, first we need to research Hydroponic Gardens, then Battle Pods and after that we need to get to work on those gyro-destabilizers. ONLY THEN WILL WE BE MASTERS OF ORION!

Re:cool

[Anonymous Coward]

Hydroponic Gardens
Check.
Wait . . . what were we talking about?

Re:cool

[marco.antonio.costa]

Farms. Hydroponic Farms... and hell, those gyro destabilizers were so freakin unbalanced. :-(

Re:cool

[Trent Hawkins]

hey, it's the only way you can rush Orion's guardian.

ION drive

[Anonymous Coward]

So, basically, this is simply just an evolution of the good old ION drive thrusters from sci-fi days of yore, and actual implementation on a small handful of real spacecraft.

Hrm, problematic.

[Anonymous Coward]

I guess the Soviet reversal meme doesn't work here, since the plasma-rocket really does propel you.

In Soviet Russia, rocket plasma...you...propel?

Re:Hrm, problematic.

[ByOhTek]

In Soviet Russia, you propel plasma rocket. yeah. It works. You just started backwards.

horray!

[nawcom]

we will bring the name of Jeebus to Mars before the Apocalypse that Revelations speaks of begins.

*runs away after starting un-needed religious flamewar*

Electrically powered engine?

[SupremoMan]

I can see the Big Oil putting a stop to this ASAP!

Re:Electrically powered engine?

[Anonymous Coward]

Because Big Oil has anything to do with space travel.

You know, because we don't already use non-fossil fuels like, oh, hydrogen and oxygen.

Not only are you trolling, but your being an idiot about it too.

Re:Electrically powered engine?

[SupremoMan]

Or it could just be a joke, and you could really fail at grasping it....

Re:Electrically powered engine?

[vuo]

And commercially available hydrogen is a fossil fuel, being made from natural gas.

But the radio signals

[Anonymous Coward]

...have to be playing Magic Carpet Ride

Re:But the radio signals

[actionbastard]

No they will be playing, 'Heavy Metal'. by Don Felder. That way you'll get to experience the 'Awesome Bewbage'.

Scotty

[arizwebfoot]

But . . .Cap'n I"m giving her everything she's got!!

Re:Scotty

[Amorymeltzer]

Too soon man, too soon.

New, it is not

[ivanthered]

The VASIMIR has been in developement since 1979.
http://en.wikipedia.org/wiki/Variable_specific_impulse_magnetoplasma_rocket

I wonder where they will get the 200 kW to drive it from?

-------------
http://borislegradic.blogspot.com/

Re:New, it is not

[Fast Thick Pants]

Sounds like a job for a small, contained nuclear reaction.

Re:New, it is not

[Low Ranked Craig]

That article indicates a thrust of .5N That sounds awfully low to me. For comparison the force of Earth's gravity on a human being with a mass of 70 kg is approximately 687 N. (from Wikipedia) did they mean .5kN?

Re:New, it is not

[qoncept]

I'm sure in 1979 they could walk in to any corner drug store and buy plutonium, but this is 2008. No, no, the only thing that could generate that kind of electricity is a bolt of lightning, but unfortunately you never know when or where it's going to strike.

Re:New, it is not

[StormShaman]

3 nuclear reactors, as the video's summary states. If nuclear reactors can provide 1.21 GW, 200 kW should be a breeze.

Re:New, it is not

[Anonymous Coward]

Nice Back to the Future reference.

Re:New, it is not

[luzr]

Actually, for ion engine, 0.5N is quite a lot.

You have to consider that these engines are meant to be ON for very long periods of time. Small acceleration accumulates to pretty big velocities if you can afford to leave engines on.

And with this engine, you can.

Re:New, it is not

[Nef]

Seriously, it's only 200 kW? That being the case, a few square meters of solar panel should do just fine, even at Mars like distances, you'd still be getting enough energy that it would be trivial ( something like 5 square meters would be sufficient at even Mars furthest distance of 2.5EE6 KM from the sun)

Yes, I know my figures aren't exact, but this is /., so I'm sure someone will come along and actually do the calculations.

Re:New, it is not

[Squiffy]

Seriously, it's only 200 kW? That being the case, a few square meters of solar panel should do just fine, even at Mars like distances, you'd still be getting enough energy that it would be trivial ( something like 5 square meters would be sufficient at even Mars furthest distance of 2.5EE6 KM from the sun)

Yes, I know my figures aren't exact, but this is /., so I'm sure someone will come along and actually do the calculations.

From the article you linked, the Earth gets 1366 Watts per square meter. 200000/1366 = 146.4.

Near Mars, which gets about half of that flux, you need about 300 square meters.

Re:New, it is not

[glebfrank]

Near Mars, which gets about half of that flux, you need about 300 square meters.

So, a couple of 10 by 15 meter panels. That doesn't sound out of the question.

Re:New, it is not

[Anonymous Coward]

you need a square root symbol in there somewhere, right?

Re:New, it is not

[Low Ranked Craig]

Yes, but the engine they refer to uses 50kW. I don't see how 50kW translates into .5N

Re:New, it is not

[Anonymous Coward]

Since solar panels are not 100% efficient, more like 30% or so at best, you'd need a little more than 300 square meters. Perhaps as much as 1000?

Re:New, it is not

[Anonymous Coward]

That 1366 W/m^2 is also assuming perfect perpedicularity to the incoming photon. The receivable power drops with the angle of reception, and this is all before the solar panel extracts a mere 25% of the photon's energy.
So assuming perfect perpendicularity, you're talking in the range of 1200 square meters at mars distances.

Re:New, it is not

[Squiffy]

So, a couple of 10 by 15 meter panels. That doesn't sound out of the question.

I wasn't arguing against the use of solar panels. I was correcting OP's arithmetic.

I forgot to include a treatment of the actual efficiency of the solar panels we know how to build. We can build 18% efficient panels, and we might have figured out how raise that efficiency to 50%, so the actual area would be between 300/.5 and 300/.18 (i.e. 600-1700) square meters.

Re:New, it is not

[Anonymous Coward]

Just wire up the clock tower and wait for lightning to strike...

Re:New, it is not

[Anonymous Coward]

No, it is not new. I saw it firsthand three years ago. Hasn't changed much since.

Re:New, it is not

[Anonymous Coward]

200kW!! 200kW!! Great Scot!

Re:New, it is not

[snookums]

Well, a power/force conversion is a bit of an odd thing to try and do. In "traditional" applications, you can say Power = Force.Velocity, but that really only makes sense in a situation where you're powering a vehicle at constant velocity against some opposing force (e.g. drag or friction).

If that were the case, this drive could keep something on the move at 100 km/s, provided the drag on the vessel was only 0.5 N. I have no idea what the actual drag would be on a space ship in inter-planetary space.

Re:New, it is not

[GleeBot]

A bit simplified, but here are the basic physical relationships:

Power = Energy / Time.
Energy (kinetic) = 1/2 Mass * Velocity^2.

Force (thrust) = Impulse / Time
Impulse = Mass * Velocity.

Over a period of 1 second (Time = 1):

Energy = 50 kW * 1 second = 50 kJ = 50000 kg m^2/s^2 = 1/2 MV^2
M = 2 (50000 kg m^2/s^2) / V^2

Impulse = 0.5 N * 1 second = 0.5 kg m/s = MV
M = (0.5 kg m/s) / V

(0.5 kg m/s) / V = 2 (50 kg m^2/s^2) / V^2
V = 2 (50000 kg m^2/s^2) / (0.5 kg m/s)

V = 200 000 m/s = 200 km/s
M = 2.5e-6 kg = 2.5 mg

Summary: They're pushing a very very tiny amount of mass very very fast. For a given amount of thrust, this is very efficient in terms of mass, terribly wasteful in terms of energy.

Re:New, it is not

[Anonymous Coward]

300sqm sounds a lot until you realise a 30mx10m sheet would do the job - and that's not so big.

Re:New, it is not

[mosb1000]

for a rocket it's like this:
power = .5 * propellant mass flow rate * propellant velocity ^ 2
thrust = propellant mass flow rate * propellant velocity

Re:New, it is not

[Anonymous Coward]

Anybody know how the different atmospheres would affect the amount of sunlight reaching the surface?

Ion drive?

[Anonymous Coward]

How does this compare to an Ion Drive system?

Engine?

[jdb2]

Engine? The scaled down test version might use something "conventional" as its power source, such as an RTG. But, in order for the VASIMIR to work at full-scale, say in a human Mars mission, the power source is going need a VERY large energy density -- something not achievable with any known and tested chemical reaction. I have no idea why they call the power source the "engine" but perhaps it's to placate the environmentalist wackos who will go nuts after hearing the obvious : the "engine" or power source is a nuclear reactor. It will be interesting ( and probably funny ) to see how this plays out in the long run if NASA sticks with this technology.

jdb2

Re:Engine?

[kestasjk]

Because NASA have never taken nuclear power sources up into space before..

(I actually feel like I need to specifically say; they have, regularly. Voyager hasn't been sending data back to us for the last 30 years (and the next 30) from inconceivable distances running on biofuel.)

Re:Engine?

[samkass]

I think the parent poster was trying to differentiate between an RTG (like Voyager has) which relies on the natural decay of radioactive isotopes and a full-bore nuclear fission reactor which induces decay with a neutron chain reaction.

Re:Engine?

[somepunk]

Good luck with that. Not only a nuclear reactor, but a heat exchanger, a turbine, and a generator. That's a lot of complexity for a space mission. There are more direct ways to generate electricity with nuclear reactions, but none are really practical for this sort of power output, that I'm aware of. I'm thinking a more straightforward application of nuclear power would work better. Something like this.

Re:Engine?

[jdb2]

I think the parent poster was trying to differentiate between an RTG (like Voyager has) which relies on the natural decay of radioactive isotopes and a full-bore nuclear fission reactor which induces decay with a neutron chain reaction.

Exactly.

jdb2

Re:Engine?

[kestasjk]

Oops, missed the RTG part, my mistake. Looking back 200kW is a bit much for an RTG

Re:Engine?

[somepunk]

a better link.

Re:Engine?

[jdb2]

Good luck with that. Not only a nuclear reactor, but a heat exchanger, a turbine, and a generator.

Uhhhhh? Have you ever heard of nuclear thermal rockets? NASA's NERVA program? You know a nuclear reactor can heat substances other than just water. I don't know if you were trying to be funny because "a turbine, and a generator" is just stupid.

That's a lot of complexity for a space mission.

And what space mission is not complicated? There's this thing called "technology" that improves exponentially with time and better technology allows greater complexity.

There are more direct ways to generate electricity with nuclear reactions, but none are really practical for this sort of power output, that I'm aware of. I'm thinking a more straightforward application of nuclear power would work better. Something like this.

I had thought of Antimatter, but we're talking about a near term mission that uses proven and tested technology. ( for its energy source ) Maybe in 50 years we'll be using antimatter for all our energy storage needs, but that implies we'll have large supplies of Anti-Hydrogen ice. Can you tell me where I can buy some today? ( By the way, I'm not a skeptic when it comes to Antimatter based energy storage and propulsion. The problem now is that current particle accelerators are designed to study particle physics, not to produce antimatter. In fact, Robert Forward showed that if we were to build accelerators specifically designed to produce antimatter,( perhaps a special linear wake-field accelerator ) we could potentially produce at least 1 milligram per year at a cost of only around a 10 million dollars. If one where to use many accelerators in parallel that where able to produce higher energies, that amount might be up in the gram-kilogram range.)

jdb2

Re:Engine?

[avandesande]

I know this technology is in its infancy but beaming microwave energy to an antenna might work.

Re:Engine?

[luzr]

Actually, current solar power of ISS is around 100kw (350 m^2 of solar panels).

So you can perhaps power VASIMIR even using the sun.

No doubt, small nuclear reactor would be an excellent idea too, especially for Mars and further missions....

Re:Engine?

[roystgnr]

Have you ever heard of nuclear thermal rockets?

Whether he has or hasn't, he may have instead been talking about an electric rocket, such as the one described here and discussed here. I'd say that calling him "stupid" for that was rude, but mostly it was just perplexing.

Re:Engine?

[toby34a]

It will be interesting. However, we've known for a long time that a nuclear reactor would be the best fuel source for a space vessel. Truth be told, it's probably safer to put a nuclear reactor in a spacecraft then in a submarine or aircraft carrier, and the Navy does that all of the time (and it would be more environmental... out in space, you wouldn't have the radioactivity in the oceans). Considering most sub reactors get >100 MW, 200 kW isn't a big deal, and you can power the ship off of it too.

Re:Engine?

[PeterBrett]

Good luck with that. Not only a nuclear reactor, but a heat exchanger, a turbine, and a generator. That's a lot of complexity for a space mission.

Look up the SP-100, which was an interesting NASA project designing a small nuclear fission reactor specifically for safe space use. One of the nice things about running a reactor in space is the fact that you only need radiation shielding in the direction where you've got sensitive equipment (i.e. crew). One of the bad things about running a reactor in space is trying to keep it cool.

Re:Engine?

[jdb2]

Have you ever heard of nuclear thermal rockets?

Whether he has or hasn't, he may have instead been talking about an electric rocket, such as the one described here and discussed here. I'd say that calling him "stupid" for that was rude, but mostly it was just perplexing.

I've you had read the article, it explains that "The Vasimir involves the injection of a gas such as hydrogen into an engine that turns it into a plasma." The most direct method of doing that would be to pass it through the reactor core. ( assuming you're using a reactor that can produce high enough temperatures ) I admit I thought he was talking about some type of conventional light water reactor, hence my comment. And I did not call him stupid, I called the idea of boiling water to produce energy on a spacecraft "stupid". ( or maybe I should have said "out of place" ) If indeed you were to reject thermoelectrics and go with a turbine design, I would expect it would be a compact closed-loop high temperature gas reactor that used something such a Helium for it's cooling and heat capture.

Maybe you should think before posting patronizing "watch your behavior" comments from your higher level of self decreed moral superiority.

jdb2

Re:Engine?

[CrimsonAvenger]

It will be interesting. However, we've known for a long time that a nuclear reactor would be the best fuel source for a space vessel. Truth be told, it's probably safer to put a nuclear reactor in a spacecraft then in a submarine or aircraft carrier, and the Navy does that all of the time (and it would be more environmental... out in space, you wouldn't have the radioactivity in the oceans). Considering most sub reactors get >100 MW, 200 kW isn't a big deal, and you can power the ship off of it too.

Submarine reactors don't dump radioactivity into the oceans, either. The primary loop (the water moving from the reactor to the steam generators) is a closed loop. The secondary loop (the steam from the steam generators to the turbines to the condensers) is also a closed loop. The only seawater is the coolant for the condensers, which never comes in contact with the (non-radioactive) water of the secondary loop, which (non-radioactive) water never comes into contact with the (not terribly radioactive) water of the primary loop.

I agree that 200KW isn't that big a deal. What you're looking for is the highest power to mass ratio reactor you can manage. Which isn't necessarily the same as the size range for a submarine reactor, since there isn't an ocean out in space to dispose of the waste heat from the secondary loop. Getting rid of that waste heat would likely be the largest part of the mass of the reactor used to power a VASIMR.

Re:Engine?

[lgw]

Of course, the fission reactor is actually *safer* during launch than a plutonium RTG, but that won't stop the nonsense. Uranium is a toxic heavy metal, much like lead, but is not meaningfully radioactive. Of coruse, one you turn the reactor on you get all sorts of nasty decay products, but you don't do that until it's safely in orbit.

Re:Engine?

[jdb2]

I think I'm in error with producing a plasma by "pass[ing] it through the reactor core" unless you're using something similar to a nuclear light-bulb setup.

jdb2

Re:Engine?

[imsabbel]

Yup.
Somewhere else, i read about using "nuclear sub" style reactors for the electricity...

Well, regarding cooling, i do not think there are two more different scenarios possible...

Re:Engine?

[ErikZ]

Within the inner solar system, that sound possible. But the farther you go out the less power you get from the sun.

With a reactor you wouldn't have to worry about a rock destroying one of your solar panels.

Honestly, if I were to plan a big mission, say, a Mission to Mars, I'd have both.

Re:Engine?

[Anonymous Coward]

Good luck with that. Not only a nuclear reactor, but a heat exchanger, a turbine, and a generator. That's a lot of complexity for a space mission.

Look up the SP-100, which was an interesting NASA project designing a small nuclear fission reactor specifically for safe space use. One of the nice things about running a reactor in space is the fact that you only need radiation shielding in the direction where you've got sensitive equipment (i.e. crew). One of the bad things about running a reactor in space is trying to keep it cool.

I am not thermodynamics expert but is cooling really an issue? Wouldnt putting the reactor in the vacuum of space overcome this?

Re:Engine?

[Bonobo_Unknown]

Just hook the sun up to the back of the ship.

Re:Engine?

[mosb1000]

I am not thermodynamics expert but is cooling really an issue? Wouldnt putting the reactor in the vacuum of space overcome this?

You would have to design the system to dissipate the heat that was generated. The vacuum of space vary bad at transferring heat, but space is extremely cold, so it balances out a little. You wold probably need to use a high temperature gas reactor to get temperatures high enough to dissipate the power. Gas reactors are also well suited to space applications because of their light weight.

Re:Engine?

[a_real_bast...]

Massive coolant-capillary filled wings, a la 2001 (book-version) Discovery?
If you're using a reactor in conjunction with solar (any redundancy is good, yes?) you've already got the wings - it's "merely" a case of making sure the reactor heat won't melt the solar panels...

Re:Engine?

[PeterBrett]

Interestingly, one of the ways that solar panel lifetime can be extended in a high-radiation environment is to run them at about 400 K...

Re:Engine?

[a_real_bast...]

Do you want to submit the idea to NASA, or will I? (",)

Re:Engine?

[Anonymous Coward]

Just tell the eviro nuts that nasa is helping rid the planet of teh evil nukes gy sending them into space.

Re:Engine?

[roystgnr]

I called the idea of boiling water to produce energy on a spacecraft "stupid".

Oh, and in case you ever actually read this: go back and reread the "stupid" comment you replied to. It said nothing about boiling water.

Re:Engine?

[ktismael]

In its most general form, "engine" just means something that provides power to do mechanical work. Typically, the main propulsion power source for a transport is called the engine, no matter what the power source actually is. Even in a modern aircraft carrier or steamship, the place where the work is done is called the engine room, even though its a nuclear reactor or boiler and steam turbines (heat engine) in there. So its just what you call it when you don't specify exactly what the propulsion will be.

Re:Engine?

[jdb2]

I called the idea of boiling water to produce energy on a spacecraft "stupid".

Oh, and in case you ever actually read this: go back and reread the "stupid" comment you replied to. It said nothing about boiling water.

Do you have basic reasoning abilities? I was referring to my absurd mistaken idea that the OP was talking about a light-water reactor, which would use steam. Please read before you post.

Re:that's all good, but..

[Anonymous Coward]

... does it run 1080p?

Plasma cosmology posts inbound!

[Sockatume]

Prepare for wackiness in 3, 2, 1...

Re:that's all good, but..

[X0563511]

No. Will this 'joke' blend?

What is the power source?

[MobyDisk]

What is the power source for these drives? Was deep-space I powered purely by solar power? Can that produce enough power to be useful? Or is something like an RTG or a nuclear power source more appropriate? I am also curious as to how much plasma they need to carry with them. I assume they eventually run out, but I gather that a very small amount lasts for a long time.

It would be awesome to see a purely electrically powered engine that required no fuel mass at all. I guess this is the closest thing we can get?

Re:What is the power source?

[X0563511]

Most likely an RTG would be used, but one "hotter" and shorter lived than what deep space 1 had. After all, it would only need to last a year at most rather than the years upon years the cooler ones go.

Re:What is the power source?

[MobyDisk]

I don't think Deep Space one had an RTG. It's not mentioned in the wikipedia article, and I can't find it on NASA's site about DS1 either

Re:What is the power source?

[X0563511]

Hmm, I was thinking of voyager. Not sure about deep space 1 then!

Re:What is the power source?

[Anonymous Coward]

The power source is old plasma TVs, duh.

Or wait, do plasma TVs come out of the exhaust?

I forget how that works. Either way this explains why we still have so many.

Re:What is the power source?

[rbanffy]

DS1 was powered by solar panels. They were very high-efficiency compared to other models of the time.

A nuclear reactor poses another set of problems - it's really hard to get rid of excess heat in a vacuum. Those fins you see between the yellow tanks in the YouTube video are radiators. It's interesting that the ship appears to use three very big RTGs for power placed in long structures far from the crew compartment but the main source of radiated heat seems to be the engine.

But it's an interesting video.

Re:What is the power source?

[XcepticZP]

Didn't you RTFA? They don't carry plasma. They turn a gas into plasma then use it. Wait, you didn't have to RTFA to know that, you had to have read the post! lol...

And you obviously didn't read any of the posts, either. It isn't "purely electrically powered engine", it uses a gas as a "fuel mass". Could it be that this plasma you say they need to carry is also a "fuel mass"?

Hey, didn't you say that they have to carry a certain amount of plasma? The thing you suppose they "eventually run out" of? So tell me, Moby, why does a "purely electrically powered engine that required no fuel mass" need to carry plasma? You know, that stuff you said it will eventuall run out of?

Lol... Someone needs to stab whoever modded you up.

Re:What is the power source?

[MozeeToby]

A no fuel mass vehicle is impossible for all practical purposes. Newton's third law: "Every action has an equal and opposite reaction". You can't accelerate a spaceship in one direction without accellerating something else in the other.

The only possible "exceptions" are an earth based laser propulsion (in which case you are infentesimably accelerating the earth in the opposite direction) or a ram scoop which could pick up fuel as it goes and accelerate that.

This could be good but...

[Coraon]

Make sure you are not an ensign on this ship. Additionally if your in a red shirt it would be best to stay away from the plasma conduits. Or yellow shirt for the next generation of this engine.

energized using radio signals

[KeithJM]

That plasma is then energised further using radio signals

I'll bet they're broadcasting the plasma's college fight song to it.

Re:energized using radio signals

[Anonymous Coward]

that sounds cool.. they could just say microwaves... most ppl understand that... I do for all the frogs and insects tossed in when I was a kid.

microwaves to and to the reaction is pretty cool but these guys are going to be using microfusion reactors i hope. the energy payoff will hopefully out do the input.

Re:energized using radio signals

[SlowMovingTarget]

Nah, AC/DC man! Gotta get it charged up!

FYI

[Anonymous Coward]

Just to make sure people know, VASMIR is basically an Ion engine that you can throttle the Specific Impulse. Hence if you need a sudden acceleration you can make that happen, but at the cost of fuel efficiency, or on the flip side if you need something efficient and don't care how long it takes either way VASMIR is the engine for it...I really look forward to when they start using it regularly

The drive was tested long ago . . .

[mmell]

back in 1975 - or was it 1999?

Oh well, that's typical of /., isn't it?

Re:that's all good, but..

[Anonymous Coward]

No. Will this 'joke' blend?

Well you can't use the Soviet Reversal, because the plasma engine really does propel you, so 'will it blend' and 'does it run Crysis' are about the only meme options left.

Ad Astra

[Anonymous Coward]

I was surprised to see that NASA allowed this development to go on in Costa Rica. Chang-Díaz may have the company in Texas, but the bulk of the operation is out of Costa Rica. Little Security on this project. In fact, if you hire on in America, you need a security clearence, but in Costa Rica, none. More importantly, the bulk of the design work is being done in Costa rica.

Re:Ad Astra

[wiredlogic]

There's no way to militarize the technology. These engines are too impractical for spur of the moment near earth operations.

One-way Ticket.

[Anonymous Coward]

I didn't see a video of anyone coming back.

JG.

Re:that's all good, but..

[ag3ntugly]

... does it run linux?

Re:that's all good, but..

[jgtg32a]

If its plasma doesn't that mean it will be over 9000?

UFOs

[4D6963]

Reminds me that lots of UFOs reported by pilots and military personal are reported to be surrounded by plasma. So if the aliens use that to achieve their blazing speed we must be on the right direction.

Just make sure...

[mdm-adph]

...and get the ownership rights for the drive squared away before you make the trip to Mars -- the last time this happened, the resulting legal battles (between the UN and some free-love hippie with a strange fixation for water) lasted for years.

Re:Just make sure...

[kneemoe]

nice REF, too bad it seems to be lost on so many....

Re:Just make sure...

[Anonymous Coward]

I Grok.

Impulse Power

[Republican Gun]

Actually it's impulse power. Warp is creating a bubble around the vehicle and moving the universe. At least that is what I learned in a Futurama episode.

Re:Impulse Power

[Anonymous Coward]

I learned that I could invent a 300% efficiency engine in a dream and forget about it in another dream.

Re:Impulse Power

[Anonymous Coward]

Presumably other vehicles in warp at the same time would get shifted by your warping even though they're in a bubble of their own outside of normal space, otherwise things would be problematic. You'd need some sort of subspace semaphore so only one ship warped at a time. That'd be awkward.

Re:Impulse Power

[ceoyoyo]

Except impulse power is reactionless. This might be what they use for the maneuvering thrusters though.

Use for terresttrial power generation?

[cryfreedomlove]

Can we use this puppy on earth to generate electricity in a cost efficient way?

Re:Use for terresttrial power generation?

[X0563511]

No, this uses energy with fuel to function. What your asking isn't be very far from asking "will an electric motor generate electricity in a cost efficient way?"

Re:Use for terresttrial power generation?

[swb]

I think you meant "...in an energy efficient way."

Because an electric motor will generate electricity in a cost efficient way, provided you're not paying for the electricity input!

Re:Use for terresttrial power generation?

[JesseMcDonald]

No, this uses energy with fuel to function. What your asking isn't be very far from asking "will an electric motor generate electricity in a cost efficient way?"

Seeing as how an electric motor doubles as a simple electric generator ... I think you picked a bad analogy. It's more like asking whether an internal combustion engine can produce gasoline, since the combustion reaction, like the heating and dispersal of the ions, can't easily be reversed.

Re:Use for terresttrial power generation?

[PeterBrett]

What your asking isn't be very far from asking "will an electric motor generate electricity in a cost efficient way?

You jest, but in hydro/wind power stations where the rotational frequency of the turbine blades doesn't often match the grid frequency, they used to use electric motors and synchronous machines coupled together to convert between the two.

Nowadays the push is towards solid state conversion, usually based on IGBTs, which results in convertors which are smaller, cheaper, more reliable and easier to maintain.

Re:Use for terresttrial power generation?

[znerk]

What your asking isn't be very far from asking "will an electric motor generate electricity in a cost efficient way?"

Actually, an electric motor can generate electricity... If you apply electricity to an electric motor, it generates motive force. If you instead apply motive force, it generates electricity.

Physics comprehension ftw!

(for more information, google "generator", "motor", "electricity" and "electromagnetics")

Re:Use for terresttrial power generation?

[X0563511]

Um, you just said the same thing. By generating electricity you... generate electricity??

An electric motor and generator are the same thing, only the input is swapped.

Re:Use for terresttrial power generation?

[znerk]

In response to:

No, this uses energy with fuel to function. What your asking isn't be very far from asking "will an electric motor generate electricity in a cost efficient way?"

I said:

Actually, an electric motor can generate electricity... If you apply electricity to an electric motor, it generates motive force. If you instead apply motive force, it generates electricity.

Physics comprehension ftw!

(for more information, google "generator", "motor", "electricity" and "electromagnetics")

To which you responded:

Um, you just said the same thing. By generating electricity you... generate electricity??

An electric motor and generator are the same thing, only the input is swapped.

To which I will respond with:
Read it again, but this time try to actually comprehend what you are reading. I have added emphasis to my original statements, in an attempt to show you where you apparently failed to notice the difference between what I wrote and what you seem to have read.

I would also like to point out that I was responding to someone who was deriding someone else for asking if this motor could produce electricity, and used an electric motor as their (flawed) analogy.

For more information, see the entire thread based on the original query.

Oh, I almost forgot... Reading comprehension ftw!

Re:Use for terresttrial power generation?

[X0563511]

Patronizing ftw!

You could look beyond the raw text of what I wrote, use a wee bit of brain power, and understand exactly what I meant. And if you don't, you could try responding without that patronizing tone. Because after that, ANYTHING you say/write in response will be discounted. Good way to win an argument, that!

Re:Use for terresttrial power generation?

[znerk]

Patronizing ftw!

You could look beyond the raw text of what I wrote, use a wee bit of brain power, and understand exactly what I meant. And if you don't, you could try responding without that patronizing tone. Because after that, ANYTHING you say/write in response will be discounted. Good way to win an argument, that!

Ok, there are several things wrong here. I'll start with the simplest: I was discussing and/or debating, not arguing. If you want to argue, head down the hall to room 12A.

As for looking beyond the raw text of what you wrote: Was I supposed to somehow read between the lines and see something that wasn't there? You (mistakenly) attacked my (valid) point, then went on to restate and (over)simplify the same information.

As for understanding "exactly" what you meant: See the above paragraph. Oh, and from what I can tell, since you simply restated my post in an argumentative tone, I'm still not clear on what you're arguing about.

As for my patronizing tone: You're right. I should have considered that you would be an imbecilic pedant who was not actually interested in imparting information. I won't bother to ask you to reread this thread with an effort towards achieving some sort of comprehension, as it is apparently beyond your capabilities.

Re:that's all good, but..

[X0563511]

Have we considered the option that no meme is required?

I wonder, aggregate across the internet - how much storage, energy, and bandwidth is wasted by pointless memes?

Better Names

[N8F8]

How about the Franklin drive or Chang-Diaz Drive?

VASIMR Info available on Atomic Rocket Page

[dlapine]

Try this Atomic Rocket website for some more information on this type of engine outside of Wikipedia. What's interesting about this type of engine is that it's capable of trading thrust (what you want to liftoff) for Specific Impulse (what you want in orbit to get best reaction mass efficiency).

This is a pretty good site for information on all types of potential/possible/theoretical propulsion systems, and what it would take to do "real" solar system space travel. That being said, space travel (even within the bounds of just our solar system) via our current level of technology bites.

As someone else noted, this type of propulsion requires about 10MW of electrical energy to function. That energy is not provided by the propulsion system. Something else has to provide it in a compact, dense and energetic form- namely a nuclear reactor onboard the craft. That's why this type of engine shows up at the "Atomic Rocket" website, even though the engine itself doesn't use any nuclear reactions. Some people might not appreciate that the exhaust is not radioactive, as the power plant is just used for electricity.

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. Unfortunately, it also requires a nuclear reactor, a VASMIR engine, a large amount (50-75% of the whole thing) of reaction mass, and probably, wings.

Re:VASIMR Info available on Atomic Rocket Page

[NewbieProgrammerMan]

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.

Re:VASIMR Info available on Atomic Rocket Page

[dlapine]

Hmmm, you're correct. The Atomic Rockets site shows that while a VASMIR can generate up to 400 Newtons in "low gear", it doesn't have a thrust to weight ratio even close to 1. Darn. I was hoping for a cool "Buck Rogers" style craft. In my excitement I forgot to check the thrust numbers.

So, any spacecraft using this method requires "a nuclear reactor, a VASMIR engine, a large amount (50-75% of the whole thing) of reaction mass, wings" and some means of getting it to orbit.

I do think I mentioned that space travel using our current level of technology bites...

Re:that's all good, but..

[oldspewey]

I wonder, aggregate across the internet - how much storage, energy, and bandwidth is wasted by pointless memes?

... and on the day that the internet crosses some critical threshold in computing and storage capacity and actually becomes a self-aware entity, will it be really annoying?

Where are the Bad Name police...?

[Anonymous Coward]

Why does this have to sound like a treatment for "feminine itch"? Seriously.

Hmmmm...

[tiny1877]

Is it going to burn out after 2 months like my 2 42" Panasonic plasma screens?

C02???

[Anonymous Coward]

Here's a thought, why don't they use carbon dioxide instead of precious hydrogen... since we're TRYING to get rid of that crap (C02)!

Re:that's all good, but..

[anti-human 1]

It is likely that your sibling poster is correct (#24501309), over 9000.

Uhhhhhh

[SengirV]

That's easy. A ZPM, you silly person.

Re:that's all good, but..

[ThomConspicuous]

I'm sorry but, in Soviet Russia you will propel the plasma engine.

Re:that's all good, but..

[Lysdestic]

Will nVidia release new drivers to help the plasma drive run smoothly?!

"former" astronaut?

[Zadaz]

How can anyone be a "former" astronaut? I thought once an astronaut, always an astronaut. It's not like they can take going into space away from you.

Re:"former" astronaut?

[ceoyoyo]

Most of the definitions for astronaut are along the lines of a person trained for or participating in space flight.

Like a janitor is someone trained to or engaged in cleaning buildings.

Once you retire you become a former astronaut (or janitor), as you no longer do it and, particularly in the case of an astronaut, your training is probably out of date too.

whatcouldpossiblygowrong

[Tmack]

Sounds like a great idea given their success with other experimental electrically based thrusters

tm

Direct solar heating

[avandesande]

Another option would be to pump the plasma with solar power directly; a gas like CO would be a good candidate. You can get temperatures of over a million degrees.

http://www.allbusiness.com/professional-scientific/scientific-research-development/155648-1.html

space dust and debris?

[Satanboy]

With this kind of speed, I would be concerned with a random piece of dust hitting the ship and possibly tearing a hole in it. I know that orbital debris is a real concern due to the speed at which the shuttle orbits the earth.

We can see from this website that orbital debris can be an issue:

http://orbitaldebris.jsc.nasa.gov/photogallery/photogallery.html

What about other forms of space debris? If a ship is moving at such speed to be able to reach mars in 60 days, (that's 1440 hours) and the shortest distance between earth and mars is on average 36,000,000 miles, that would equate to around 25000 miles an hour.

36000000 / 1440 = 25000 --- (unless my math is that off)

So at the slowest, the ship is going to be in real danger from things like space dust and even small meteors we may not know the trajectory of.

Don't get me wrong, I think it's awesome they are working on new engines, I just wonder at how they are going to protect the travelers.

Re:space dust and debris?

[grahamd0]

We're not quite up to deflector shield technology yet, but maybe they could try polarizing the hull plating?

Looks too much like Space:1999

[KudyardRipling]

Somewhere in NASA there is a stash of Space:1999 DVD's or even laserdiscs. The concept craft in the YouTube video looks like a rip-off of the spaceships in the episode Dragon's Domain. Where's Adagio for Strings in G Minor by Tomaso Albinoni for the soundtrack? Where's the monster with the spotlight eye and tentacles (complete with guy wires) that eats humans and spits out the carcasses so speedily one thinks "skateboard under prop"? Oh, did I forget the "out of focus spinning hubcap" visual effect?

On high, Lew Grade must be laughing...

Re:Looks too much like Space:1999

[KudyardRipling]

Three engines in a triangular formation? Egads! It's the Super Swift!

I can hear someone say "but like, that never got off the drawing board!"

Here come the walking piles of egg foo young and vegetable lo-mein (with shaving gel oozing out)...

Yep, I've been on the brain machine too long...

Re:that's all good, but..

[Anonymous Coward]

It has already begun

Re:that's all good, but..

[grahamd0]

"I can has DESTROY ALL HUMANS? LOLZ."

[The slashdot yelling filter has not achieved the level of sentience necessary to comprehend satire.]

subspace CSMA/CD

[scotsghost]

this problem reminds me of multiple computers talking on an ethernet hub. the solution? use a sort of subspace CSMA/CD. establish your warp bubble in a random phase. observe for a bit. if the universe is moving, someone else is using that phase: choose another phase and try again.

Re:subspace CSMA/CD

[lupis42]

I can just imagine the endless fun when two ships with the same random seed try to jump at once.

Re:Yes, attach it to the ISS Yeh, cuz if they cras

[davidsyes]

Yeh, because if they crash into a star, they will be MORE interesting than the New Plasmatics... And, crashing into a planet would me severely localized plastic deformation by plasma injection...

(When I first saw the header, I thought Plasma Disk Drives? WHoaaa, THAT'LL be some HOT data...)

Re:Yes, attach it to the ISS On just abut any gas?

[davidsyes]

Well, HELL, just take a bunch of G.M. beans and fart you way across the galaxy. Gives a new meaning to our triumphant gas giants... Stellar gases ... This could have quite a deep impact full of RAMifications... Just better having enough shielding/isolation tween the genny and the ass, or the crapper will turn into an APCTA -- Asstral Projection/Corporeal Teleportation Apparatus...

Exactly What Neds To Be Done

[reallocate]

This is exactly what needs to be done: Provide more speed.

Combine that with a cheap and reliable way to get to LEO and you have the beginnings of a real exploration of the Solar System.

Average speed ?

[Anonymous Coward]

Looking at the concept video, I was attempting to calculate the average speed of a vessel using this new drive; however, we know that the distance between Mars and Earth can vary between 36 million miles to over 250 million miles. Do we know which figure they used when theorizing the 60-70 day trip to the red planet?

It's VASIMR actually...

[marco.antonio.costa]

This is exactly what needs to be done: Provide more speed.

Combine that with a cheap and reliable way to get to LEO and you have the beginnings of a real exploration of the Solar System.

This engine looks really cool, I've been checking it out for awhile. I really think plasma engines are the tech we'll be using as propulsion.

This is a good trend for us to pursue. Truly SPACE-craft that don't have to be spectacularly and expensively launched and go thru the trouble of reentry every single mission.

Parent's right, what we need now is the most efficient and cheap means to get to space as possible; the new private space companies that are trying out with pure liquid fuel rockets and are failing miserably now could be on the right track. And hopefully the space elevator idea might come to be feasible in the next 50 years.

Then my friends, humanity will have moved OUT of it's parents house, and finally be free.

In Medvedev's Russia

[Latent Heat]

In Medvedev's Russia, Plasma Drive plans test on you!

Alphavoltaics

[Anonymous Coward]

Maybe an alphavoltaic generator, which would use natural alpha decay of a suitably short-lived isotope, converting kinetic energy of emitted alpha particles into current. I think there were studies done on liquid gallium, and also someone recently came out with a proposed fullerene nanotube material as some kind of fast-healing solid electrolyte. Healing is an important issue, since those energetic alpha particles can smash up your conversion material pretty quickly.

How to do those Russia jokes

[Latent Heat]

First of all, they have to be kept topical. Back in the day they were the Soviet Russia jokes, more recently "in Putin's Russia", which works because Putin is former KGB and cultivated a reputation of being a tough guy, and now, it is "in Medvedev's Russia." Medvedev may be a cipher and may be Putin's puppet, which makes it even the more to make it "in Medvedev's Russia" (name pronounced Mehd-vyehd-yev -- the Russians stick "y's" in front to dipthong-ize vowels in contrast with other Slavic languages).

Secondly, the construction you want to reverse is subject-verb-object. A lot of humor has a rather angry, aggressive substrate to it, and the object in the construction is something that gets acted on in a way that we would not give it much thought, but turned around gets rather nasty. I have the hardest time explaining the positive-passive sign convention for power flow to engineering students, but when I explain that the resistor is passive in the sense that it is acted upon, that you make it your b12ch, suddenly eyes light up with recognition. Only in the "Russia" joke, in the reversal, "you!" become the "b12ch", and the idea is that Russian and many other social systems, the individual person is the "b12ch" to a lot of personal interactions that have become impersonal, and the recognition of this sad fact from the joke makes the joke funny.

So in the classic example, "In Soviet Russia, TV watches you!" As far as I can tell, they never put spy cameras on Russian TV sets -- that meme comes from Orwell's 1984 -- and they didn't need to because all of the spying was done by your friends and neighbors who would rat you out to the NKVD or later KGB if there was enough incentive. On the other hand you-watch-TV is the normal subject-verb-object construction, and the TV is taking a very passive role, permitting itself to be simply watched and controlled through the selection of channels. On the other hand TV-watches-you! turns it around, where you are now the object of the watching, a kind of observation that demeans you as a person even if no evidence is found of you being an enemy of the state. Of course the TV doesn't do the watching, your coworker with whom you split a bottle of vodka and your neighbor who eyes up your coming and going does that watching, but it is all the same.

So someone tried to turn around "American men don't understand women, but in Soviet Russia, men actually understand women. No, no, no! Man-fails to understand-woman is the subject-verb-object construction has "failing to understand" as a kind of passive-aggressive action that is applied to "woman" as the object -- a man in American society is in a passive-aggressive way treating a woman in his life as an object by failing to understand her well enough to make a relationship harmonious.

So the proper turn around is "In Medvedev's Russia" (remember to make the joke up to date and to put the y's in front of the vowels in Medvedev), "women fail to understand you!" This new joke works on so many levels. It points out that "fail to understand" is actually a passive-aggressive action that objectifies and perhaps demeans another person, but there is a little reversal humor on the riff that most men don't see it that way and consider the way a woman in one's life conceals her moods is a kind of manipulation of him. But in Russia, they have this turned around, and women get to act passive-aggressive and not respond to the emotional needs of the man in their life.

It works yet on another level, because part of Russia humor is the notion that women over there work in factories and have powerful peasant physique's whereas some of the men are wimps who dissipate themselves telling long stories over vodka. It isn't just American's having this stereotype of Russians, I am told that Serbs, who are regarded by Russians as hick "country cousins" turn this around and view Russian men as being gender-whipped. "In Medvedev's Russia, women fail to understand you!"

So with the plasma drive, the normal subject-verb

But where does the energy come from?

[Anonymous Coward]

How much energy do you need to drive an engine like this?
And where does that energy come from?
(I'd like to say nuclear fission...)

How do you keep a superconductor cool in space?

And finally - this doesn't appear to be a replacement for chemical rockets launching from earth, only something to use once you are out of the deep gravity well that we're in right now.

Eagle thrusters

[Burz]

In scifi, the Vasimir would be more likely to power this.

Skeptical here

[Lord Apathy]

I sure hope this is not the case but I've been hearing about new engine designs that will get us to Mars in days/weeks instead of months for years. So I'm going to have to hold off judgment on how great this is until I see them actually using it.

More likely I'm expecting this will be the last I ever hear of it.

Please just stop.

[roystgnr]

If you don't know that VASIMR is an electro-thermal rocket, ie. one that uses an electric power source to excite the plasma, that's okay, but in that case you should probably think twice before insulting anyone (yes, "your idea is stupid" is an unnecessary insult) who tries to correct you. If you think that being corrected when you post something mistaken and insulting is "patronizing", imagine how it looks when you try to correct people who are trying to post something factual and polite.

Re:Please just stop.

[jdb2]

If you don't know that VASIMR is an electro-thermal rocket, ie. one that uses an electric power source to excite the plasma, that's okay,

Actually, I knew, but thought that the power conversion would be too inefficient when trying to produce the plasma electrically and would reduce the thrust to a level too low needed for large-scale missions. I was wrong and corrected myself -- something you conveniently ignored.

but in that case you should probably think twice before insulting anyone (yes, "your idea is stupid" is an unnecessary insult) who tries to correct you.

First, he wasn't trying to correct me, or at least I didn't take it that way. I took his remark as inflammatory because of his use of "good luck with that" with reference to using a nuclear reactor in space -- and that comment *was* stupid as there has been a huge amount of work on space-based reactors ( look into the history of the U.S. Atomic Energy Commission and eg. projects Kiwi, Rover, and NERVA ) for the purposes of energy generation and propulsion in space. What was *stupid* on *my* part was mistaking his reference to "a heat exchanger and turbine" as a reference to a light water reactor, which I should have known to be absurd. It was just a misunderstanding, and your continual involvement in this with your cocky attitude of moral superiority and the need to treat me like a baby makes you everything but a Troll.

And as for "Please just stop", are you referring to my "stupid" remarks that you're obviously above, since everyone knows that you have the moral authority and anyone who dares contest what you say is either immature, stupid, or an *sshole? If that's the case then your replies to my post would seem to indicate a double standard : you are right, and I am wrong. On the other hand if you are telling me to stop because, obviously, I'm making a fool of myself by trying to defend my weak, small-minded idea that my character and intellect are being harassed because of my delusion of your misrepresentation of my remarks, then you've just proven yourself to be the cocky, condescending, self-appointed moral authority that you say you are not.

If you think that being corrected when you post something mistaken and insulting is "patronizing", imagine how it looks when you try to correct people who are trying to post something factual and polite.

Again, you misrepresent my statements, and you're continual reference to my remarks being "mistaken" and "insulting" and that they need to be "corrected" is what gives me the idea that you're getting some type of power trip out of this.

I was mistaken in the fact that I thought the OP was talking about a light-water reactor when he referred to heat-exchangers and turbines -- that was stupid on my part. But, as for you "correcting" me, obviously you neglected to read or conveniently forgot the comments I made in my previous posts such as 'I think I'm in error with producing a plasma by "pass[ing] it through the reactor core"' . I had conceded that idea of direct heating of the working fluid ( gas ) to produce a plasma was wrong and that using electricity was probably what the article was referring to.

And on the topic of you or the OP being "factual", that is highly questionable in the context of this discussion because you made that remark after I replied to "he may have instead been talking about an electric rocket" and now it appears that you are retroactively extending your *factual* statement about the plasma being produced electrically to my previous comment -- in essence, you are accusing me of lacking the ability to foretell the future. Furthermore, the OP had thrown out the possibility of conventional nuclear power and instead was referring to antimatter, so I don't see how you can draw the c

BCReason

[bcreason]

I'm waiting for the Dirt Drive . Same concept as the Vasimir but instead of throwing Hydrogen away as propellant you use Silicon, the main component of dirt.

Why use precious hydrogen that can be used to make water when you could use dirt. The Moon has dirt, Mars has dirt, most asteroids have dirt.
(Technically it's regolith, but regolith doesn't sound as cool)

I know it will take some serious engineering to make a drive that uses a solid fuel. I'm thinking vaporize it with lasers, then everything else is pretty much the same as with the Vasimir.

Advantages over Hydrogen:

• Easier to obtain
• Easier to store, no pressure vessels required.
• More compact to carry.
• Has more mass, therefore more thrust.
• Safer, non flammable and not stored under pressure. No chance for an explosion.
• Safer, wont leak away if a storage container is holed.

Congratulations!

[znerk]

Awesome, you're now one of my freaks! Thanks for caring enough to mark me as a "foe".

Incidentally, this doesn't do diddly for you having made an absurdly stupid comment, nor for your chances of winning this "argument" (think "couldn't punch your way out of a wet paper bag").

The fact remains that of the 4 people who responded to your extremely poor analogy, you chose me because you thought someone who used the term "ftw" (which means "for the win", by the way) would be a pushover, and generate more karma for you. So sorry, but just because I use slang terms doesn't mean I'm unintelligent.

Of course, this post is way off topic, and likely to be markled both troll and flamebait... but I just couldn't resist tweaking your nose yet again, seeing as your response to my refutation of your argument was to mark me "foe" instead of responding.

--
"Good way to win an argument, that!" - X0563511 (793323), my newest freak.

Re:Congratulations!

[X0563511]

No, I just don't like you. I don't really need to explain more than that.

And the whole foe/freak thing is just a way for me to bury people I don't like, so I don't get needlessly irritable. Check my foes list, and I'm sure you'll see what I mean.

Congrats on your new sig, carrying this pointless -whatever this is- out of this thread.

Re:Congratulations!

[znerk]

Yeah, just what *is* this? You still have yet to refute my argument... or even admit that you decided to be a prick just to have an argument. It's ok to make mistakes, you know, but when you try to rub other people's noses in them, it just makes you out to be an ass.

Just trying to help you in your interpersonal dealings; no offense, eh?

--
Silly twit.

Re:Congratulations!

[X0563511]

I don't know. I think we both just got all pissed at each other for no good reason, although I did start it. But that's what happens you don't get enough sleep and half your coworkers get axed - I guess you were just one of the first few outlets!

I apologize.

Gaseous Core Nuclear Reactor

[serutan]

A gaseous core reactor would radiate ultraviolet energy directly to the hydrogen, eliminating the need to generate electricity. Take a look at this article about a hypothetical design for a non-polluting, 100% reusable nuclear rocket using the Saturn V form factor that could lift 1000 tons of payload into Earth orbit and return an equal payload to a powered landing.

Watch your back Voyager

[plasmaben]

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

Please at least be coherent.

[RustinHWright]

Usually I don't bother saying this kind of thing, but dude, please at least spell simple words correctly if you're going to go so very far into the realm of the questionable. You do your credibility no favors at all by talking about "particals" that are "avaliable" in "interteller space". Though, come to think of it, you do very effectively convey the impression that you don't give a damn if what you say makes any sense or not. Which, given your comments, may be entirely appropriate after all.

Sub reactors in space

[RustinHWright]

I've read variations on this a lot of times and it always worries me.

A.) It takes a hell of a lot of technicians to run a sub reactor. How comfortable are you with adding, oh, thirty crew members to your complement just to run the reactor?
B.) Sub reactors work as well as they do in part *because* of all that water around them. Water conducts heat well and has a formidable thermal mass. Vacuum is the opposite. How many tons of water are you up for pushing out of the gravity well for your "not a big deal" reactor?
C.) Another factor in cooling is yet more tons of pumps and valves, most of which have been designed for fifty years to take advantage of gravity. Gawd knows a sub has to be able to keep running even with some degree of shift in attitude but I can't help thinking that zero-g would be a whole different kettle of neutrons.
D.) In addition, sub reactors haven't run as flawlessly as most people assume. Just including the scrams listed in, say, Blind Man's Bluff , we've seen some pretty damn scary reactor failures. Given how reliably we have found that the military covers up failures, even decades later, we have to assume that however many failures we know about, the actual safety record is even worse. I wouldn't be so ready to take their word for it or believe the conclusions of fanboys like Tom Clancy if I were you.
E.) Having said all of that, if we're going to talk about nuclear power in space, why don't we talk about existing successful examples of nuclear power IN SPACE? Voyager, anybody? Nuclear power is used in space all the time. RTGs have been in use since before most of the people on this site were born. Let's give them the cred they (and their designers and builders) deserve.

Howsabout we go one step further?

[RustinHWright]

and suggest a craft that uses, say, vaporized iron?

I don't know about you but if I'm designing a device I'm planning to trust with my life, I'll want it to run on something a bit more uniform than regolith.

anyway, your idea is dirty! ;->

Re:Howsabout we go one step further?

[Anonymous Coward]

Nah! Iron is too useful to throw away as propellant.

Of course the silicon would be processed and purified. Since silicon is often found as Silicon Dioxide (sand). You extract the oxygen and the silicon is a waste product. You could then powder or granulize the silicon to make it easy to store or pipe around.

vasimiiiiiiiiir

[Anonymous Coward]

there is no extra 'i'.

it's just vasimr.
variable. specific impulse. magnetoplasma rocket.

note the lack of an 'i' anywhere from the start of magnetoplasma and the end of rocket.

and for everyone baffled by why vasimr is cool, it's like a transmission for your ion drive (oversimplified). now you can have one source of propulsion for both 'low gear' (high thrust, low specific impulse) and 'high gear' (low thrust, high specific impulse) just by adjusting the 'magnetic choke' that controls the exhaust of the plasma.