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Comments: 277 +- Science: Ex-Astronaut Developing Plasma Rocket To Revitalize NASA on Monday October 05, @12:54PM
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TechReviewAl writes "Former astronaut Franklin Chang Diaz believes that the private sector can revitalize NASA, and his company is developing a plasma rocket to back up that claim. Chang Diaz argues that private industry can be used to develop much of the basic technology needed for space exploration, allowing NASA to focus on more sophisticated and critical components. His company, Ad Astra, is developing a variable specific impulse magnetoplasma rocket (VASIMR) that will be used to reposition the International Space Station. Last week, the rocket passed an important milestone in testing — reaching 200 kilowatts (enough to move the ISS). A video of the rocket can be seen on Ad Astra's site."
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Awesome. (Score:4, Funny)
Bonus points for the space invaders noises it apparently makes.
Re:Awesome. (Score:5, Funny)
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Summary is incorrect (Score:3, Informative)
Since the ISS only has 120-130 Kilowatts of Solar Panels, running a 200 Kilowatt motor would be difficult.
Also Kilowatts though stated in the article aren't really a measure of thrust.
The engine can operate at different levels UP TO 200 kW, but would probably have to use about half that because of the stations limitations. Though if the Motor can use waste hydrogen from the Fuel Cells/Ox Generators they are estimating it would save NASA bringing up fuel for reboosts. (From the Proposal/white paper on VASIMR)
Re:Summary is incorrect (Score:5, Informative)
VASIMR can fire for up to 10 minutes at 200 kW using trickle charged batteries.
http://spacefellowship.com/2008/12/13/nasa-and-ad-astra-rocket-company-sign-agreement-for-flight-test-of-the-vasimr-rocket-engine-aboard-the-international-space-station/ [spacefellowship.com]
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Re: (Score:3, Informative)
Thrust can be calculated by the power and the ISP:
I think it's something like this:
Thrust=Power*2/(effective velocity)
or
Thrust=Power*2/(ISP*9.81m/s^2)
So, if the power is 200kW and ISP= ~3000s (assuming 100% efficiency, where efficiency is probably more like 65%):
400,000W/(30,000 m/s)=13 Newtons
So, a thrust of 13 Newtons is possible at the low end of ISP. And, actually, thrust decreases with ISP, so ten times higher ISP (30,000s) would be about 1 Newton of thrust at 200kW.
Re: (Score:3, Interesting)
I think ion thrusters would be a better way to go for ISS boosting.
These [esa.int] calcs show the drag force on the ISS is about 0.25N.
These [wikipedia.org] tables show that to get 250 mN thrust you are going to need ~10 kW of constant electrical power. That is 8-ish % of the ISS available electrical power. It seems very do-able.
Possibly ISS electrical power is so stretched that using it to boost is considered a waste. Certainly it is possible without VASIMR.
Re:Summary is incorrect (Score:4, Informative)
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Re: (Score:3, Informative)
Since the ISS only has 120-130 Kilowatts of Solar Panels, running a 200 Kilowatt motor would be difficult.
I am sorry to go on a rant about this, but as someone who works on solar power on a daily basis, I am sick of people assuming that since something uses solar power to generate the electricity, that it will only work when the sun is shining. Ever heard of batteries? Do you honestly think that the ISS is up there, without batteries, which allow a system to draw more instantaneous power than the solar panels can supply, but can be recharged later when the system isn't drawing so much power?
I worked on the s
They've been working on this for a while now (Score:4, Insightful)
AFAIK they have been working on VASIMR for over a decade now... This isn't exactly "news"
Re:They've been working on this for a while now (Score:5, Insightful)
A non-chemical rocket that can produce that level of thrust is absolutely news, it has the potential to open up the solar system. Personally, I'd rather see research and developement into ground to orbit launch technologies, but this is a big part of moving things quickly from one part of the system to another.
To be fair, the title is what is wrong, it should be "VASIMR Tested at Full Power" not "VASIMR under developement".
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Re:They've been working on this for a while now (Score:4, Funny)
No, no, no. These VASIMR experiments are entirely new. You must be thinking of the old VALKILMER experiments.
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Re:They've been working on this for a while now (Score:5, Informative)
AFAIK they have been working on VASIMR for over a decade now... This isn't exactly "news"
I think you're mistaken, "news" and "new" aren't the same thing. If you're pining for something "new" in this "news" it's the fact that they passed a significant milestone last week.
Note: If English isn't your first language and you're mistaking "news" as the plural of "new" (which usually doesn't have a plural as it's not generally used as a noun) disregard.
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Re: (Score:3, Insightful)
Yes, they've been working on VASIMIR, and many other technologies, for decades. What makes this story newsworthy is the fact that they've passed another major milestone and are one step away from real-world implementation in the space station. Unfortunately, public opinion often weighs heavily, whether we like it or not, on which technologies get the funding to continue development. This is true in government projects, like what NASA does, and doubly true in privately funded companies like the one develo
Re:They've been working on this for a while now (Score:4, Insightful)
When I was 20, fusion was 20 years away, and it seemed likely we'd see space-baced fusion drives in my lifetime. Now I'm 40, and fusion is 20 years away ...
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That's nothing (Score:5, Funny)
Perspective (Score:5, Informative)
If you measure distance in terms of transit times, the sustainable thrust potential of this technology would make the Solar System the same size to travelers as the Earth was during the Age of Sail.
Re: (Score:3, Interesting)
Re: (Score:3, Interesting)
Re: (Score:3, Insightful)
Also, if you can physically get to an asteroid, that's the first step towards mining it, or perhaps nudging it (very, very carefully) towards Earth orbit, so as to mine it more easily.
Re:Perspective (Score:4, Insightful)
You're kidding, right?
Right now, the chances of dying on a Space Shuttle trip are a bit over one percent. That said, I'll bet if you were to offer rides to the public--knowing full-well that the odds of dying in a fiery hell of hydrazine and liquid oxygen are about two in one-fifty--I'll bet the line would be around the block before the last words were out of your mouth.
And I'd be at the front of that line.
Do you really think there's any shortage of people who wouldn't love to go to space, to explore something new? Even without any reward--hell, even if you didn't pay a salary for their service--you'd have no trouble finding volunteers. Lined up around the block, probably more than a few fist-fighting for one space closer to the head of the line.
And I'd make sure I won that fight.
In fact, you could probably make it a one-way mission--we'll send you to Mars, you'll help us with experiments, and you'll plant a flag with your name at the base, but we can't bring you home--and the volunteers would come.
Oh, yes, they'd come. Just for the chance to touch the soil of a foreign planet. The chance to travel to the great unknown, to be the first to do something truly majestic. Oh, yes, they'd come.
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Re: (Score:3, Insightful)
I can't help but notice that you're not at the front of THAT line.
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Really? (Score:3, Informative)
I was under the impression that VASMIR was a low-thrust technology (high energy, low propellant mass = high Isp, but normally with low absolute thrust). The proposed 200kW model was expected to have a thrust of 5 Newtons, according to wikipedia. Now, that's nice, but it's on the order of the smallest black powder Estes engines used to fly 50-100gram rockets for fun. It will move a space ship, but it will provide relatively low acceleration.
Since sail circumnavigation of the earth can be done in less than 18
Re:Really? (Score:5, Informative)
While 180 day circumnavigation is possible, the travelers of the 16th-18th Centuries usually took three to four years to circle the globe. That's the basis for the comparison I was making.
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Re: (Score:3, Informative)
If you measure distance in terms of available air to breathe though it's still much larger.
Really, two years or more in the Age of Sail was a very different thing. You could (and they frequently did) call to a port or some island to get supplies, breathing was free and there were much more options for ending the journey somewhat gracefully while for space travelers going back to Earth and getting safely back to the ground is the one and only option. Space is so much larger and emptier than even the oceans o
Get out of the way, NASA (Score:4, Insightful)
They should license out the Ares technology, promote competitions among the multiple private rocket vendors and focus on scientific and development missions using private vendors to provide the launch capacity.
Re: (Score:3, Insightful)
This is Huge (Score:5, Interesting)
VASIMR means the only expensive part is getting to LEO. Once there, a space tug using VASIMR can lift satellites to GEO for almost nothing (compared to today's prices). It's not really fast enough for human travel, but for moving equipment around Earth orbit (or elsewhere), it's very promising. Between this and SpaceX reducing the price to LEO, the next 10 years should be very exciting in commercial space travel.
"200Kw, which is enough to move the ISS" (Score:4, Insightful)
Re: (Score:3, Funny)
(I'd imagine 200kW is needed for regular orbital corrections for the full ISS when all modules are in place, but I'm probably wrong. But here's something better:)
No--because of NASA cuts, lawmakers have just ruled that physicists must add an additional ISS equation to quantum mechanics, governing the behavior of the ISS in orbit around Earth, so that quantization will inhibit orbital decay. They picked an equation where the only resonant energies were the only interesting orbits. Since the energies are q
Re:"200Kw, which is enough to move the ISS" (Score:5, Informative)
Can't any amount of power move the ISS just at a slower rate?
Kind of. It has to boost altitude, on average, more than 200 meters per day, just to keep up. Over and above that, yes anything will do.
There is also a scheduling issue. Currently they burn chemical thrusters every month for a couple hours. That means no "microgravity environment" for less than 1% of the time. That is OK, 99% of the time is good enough for experiments, etc. Now, if the fancy new vasmir can only boost 400 meters per 24 hours of continuous operation, then just to keep up with atmospheric drag, it absolutely must run 1/2 of the time, meaning you only get that fancy microgravity environment for 1/2 of the time. Also with respect to maintenance and reliability, that means it has to be operational about half the time or better. And finally, a 1% of the time activity means direct astronaut operation/intervention is possible, but there is not the staffing to baby sit a low thrust engine literally half the time, so it has to be highly automated.
http://web.archive.org/web/20080213164432/http://pdlprod3.hosc.msfc.nasa.gov/D-aboutiss/D6.html [archive.org]
"Reboost mode is necessary because the Station's large cross-section and low altitude causes its orbit to decay due to atmospheric drag at an average rate of 0.2 km/day (0.1 n mi/day)."
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Re:"200Kw, which is enough to move the ISS" (Score:5, Insightful)
This may be a stupid question, but if there is no perceived gravity in a "perfect" orbit, but the ISS orbit is decaying, wouldn't that mean that the decay is being caused by acceleration, causing it to be less than a perfect microgravity environment. If you, on the other hand, had a tiny thruster operating 100% of the time that kept the ISS in its perfect orbit, wouldn't that mean a BETTER microgravity environment, not a worse one? In other words, by constantly counteracting the drag of the atmosphere instead of letting it build up then using significant thrust, wouldn't you go from microgravity 99% of the time to even better microgravity 100% of the time?
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Re:"200Kw, which is enough to move the ISS" (Score:4, Informative)
If you, on the other hand, had a tiny thruster operating 100% of the time that kept the ISS in its perfect orbit, wouldn't that mean a BETTER microgravity environment, not a worse one?
In theory, yes, but in practice, good luck.
Then you need 100% reliability or 100% redundancy. I would guess they'll require the engines to be shut off during spacewalks, maybe while the shuttle is docked (who knows what effect fumes could have on the tiles, etc). Conveniently you'll need multiple separate engine systems for reliability, so after the spacewalk you just light off both primary AND backup. True 100% operation and true 100% microgravity is unlikely.
Not to mention whatever outgassing and optical effects the thrusters might have. If you only burn a chemical thruster 1% of the time every month or two, you can schedule optical and materials testing in the weeks up to a burn without interference.
Finally you would need 100% power all the time, meaning pretty much nuclear is the only option. Either that or drain the batteries in the dark and charge them in the light, with a cycle every 1.5 hours. Icky. From an electrical standpoint, better off running the thruster only in the sunlight only on excess capacity after the batteries are topped off. I'm guessing that would be about a 10% duty cycle, about ten minutes every hour and a half, although it obviously depends on solar power available and to some extent on thrust required.
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Re: (Score:3, Informative)
It isn't a stupid question, and yes, by counteracting drag thrust can get you to true freefall.
Too many cooks... (Score:3, Interesting)
Physics question (Score:5, Interesting)
Bank in 1999. electricity has been generated in space by dragging a copper tether though the earth's magnetic field (http://www.independent.co.uk/news/astronauts-seek-power-in-space-1319781.html).
Presumably this produced drag. Can't this "drag" be used for some near earth maneuvering using a mesh system to create an electromagnetic sail by which one might tack? Or is the amount of force to small to be useful?
The Electricity (Score:5, Interesting)
Despite it's high specific impulse this engine isn't the whole answer to the exploration of the solar system. Blame the inverse square law.
It may be feasible to power an slow unmanned Earth-Moon VASIMR transfer vehicle with solar, but at Mars solar radiation is only 25% as strong and at Jupiter it's 4%. So you are talking about nuclear for probes to the outer planets and for manned missions to anywhere.
There's nothing technological that would stop space-based nuclear but you just know it'll take years to get that done.
New Scientist [newscientist.com] has an article that says VASIMR + nuclear = 39-day transit time to Mars.
Re:Another ex-NASA type trying to cash in (Score:5, Insightful)
A cynical view I know. But the US Gov pays through the nose to train these guys who then just retire and try to cash in on the Washington gravy train. Just like the rest of the high level military, political and bureaucratic employees that leave gov employment in order to cash in. Typical and sad.
Why is that "sad"? Would you keep working for the Government if you had a skillset that was going to enable you to make a lot more money in the private sector? Does it also bother you when someone gets an entry level IT job and then leaves for greener pastures once they acquire sufficient work experience?
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Re:Another ex-NASA type trying to cash in (Score:4, Funny)
Um... because for us real humans, money is not our only (pointless) reason of existence.
That's just something poor people say.
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Re:Another ex-NASA type trying to cash in (Score:5, Insightful)
Or maybe, just maybe, the guy got a doctorate in plasma physics, and flew 7 Space Shuttle missions (which isn't exactly safe), directed the NASA Advanced Space Propulsion Laboratory, and is investing in plasma rocket research after his NASA tenure because he's interested in plasma physics, rocket science, and the possibilities of space flight.
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Re:Another ex-NASA type trying to cash in (Score:5, Insightful)
So we've got a _really smart_ guy we've paid to educate, paid for many years to perform exactly 7 times... I'm not about to give him a free pass just because he's got a doctorate and a handful of mission patches.
Given your flippant tone, I'm sure you'll be surprised to hear that 7 space shuttle flights is as many as anyone has ever done. Only one other astronaut has as many missions under their belt. This is because space flight is a Big Deal. Astronauts often train for years for a single specific mission.
By the way...how do you amass enough cash to personally invest significantly in this kind of endeavor, considering otherwise "normal" governmental salaries in the 70-130k/year range?Or is he primarily a front man - a very smart one - who is helping to get money from others (perhaps old colleagues with strings to government funds?) to pursue this research.
Front-man... inventor of the technology the company makes... Yeah, same thing.
I'm not saying he's not doing interesting, and possibly valuable, research, but I'm not about to give him a free pass just because he's got a doctorate and a handful of mission patches.
What does that even mean? A "pass" from what? What horrible sin has he allegedly committed? Leaving NASA after a mere twenty five years and a record number of shuttle missions? Turning his research into plasma propulsion into a real invention? Throw me a bone here!
Now, if he's made a bunch of money doing other things (dot com bubble investor?), and is pursuing this as a purely speculative path, then good for him.
Oh I see. So if he'd managed to fund this venture without having done anything productive rather than inventing a new propulsion system, then you'd be cool with it.
WTF is with these comments?
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Re:Another ex-NASA type trying to cash in (Score:5, Interesting)
I'm not sure you understand the potential that any particular astronaut has to ruin hundreds of billions of dollars of government investment. If an astronaut meant to, or just screwed up at something that may have seemed inconsequential at the time, the deaths of the people onboard would be, while publicly tear-jerking, relatively inconsequential compared to the gross loss of capital for the agency. (Less now that they're intending to stop using the shuttles altogether, but to some degree still.)
The fact that he made it through training and became an astronaut means that he was worthy of being trusted with a hundred-billion-plus dollar space ship. That's what the training is for. That's why we pay their training, and why we pay them. Not only could they die in a spectacular fireball if they make the wrong mistake--or if someone else does--but it's possible they could completely ruin NASA's chances of ever being useful again by swaying public opinion. A single person could--or could have--singlehandedly set back mankind's exploration of space by decades or longer.
And you've really got the balls to say that spending the money that he got as part of that trust to keep advancing something he loves and believes in is less respectable than if he had taken his money, gambled with it on the stock market, and taken whatever gains he had and spent them on this as an outsider?
Disclosure: I am related to a former high-ranking NASA employee, and while that doesn't make me an expert, I do have at least SOME sense of scale about the damned thing.
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Re: (Score:3, Informative)
Okay let's start off with why your nuts.
1. His Astronaut training that he got from NASA would have ZERO to do with a plasma rocket. He would get lots of training on how to operate the Space Shuttle systems and how to try and not die if things went very wrong.
2. His time in the advanced propulsion department might have something to do with with this but NASA doesn't make stuff. They may design stuff but then they have outside companies build the stuff.
In this case he is probably taking a project that was get
Re:Another ex-NASA type trying to cash in (Score:5, Insightful)
But the US Gov pays through the nose to train these guys who then just retire and try to cash in on the Washington gravy train.
Yeah he retired after "just" twenty five years [wikipedia.org]. He really screwed NASA on that one!
And what, after he retires, he's not supposed to do the most obvious things related to his education and experience? He was working on plasma rockets before he made it to NASA. So is it worse that he's planning to work on plasma rockets to sell to NASA after working for them for a quarter century, rather than going into private industry straight out of college? Why? Because it vaguely fits a stereotype of ex-government employees leaving to work for contractors?
A cynical view I know.
Yeah... What's the word where cynicism is used as a replacement for understanding? Kinda like "blind optimism", but the opposite? Blind cynicism doesn't sound right. As a cynic, I've always liked the expression "cynicism is realism plus experience". But you're not being realistic. So... what is it that you're doing?
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Re:Another ex-NASA type trying to cash in (Score:5, Funny)
I believe the word you're looking for is "hating".
As in:
"Hey, stop hating on Franklin Chang-Diaz just because he's smarter than you and makes way more money."
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Re:Another ex-NASA type trying to cash in (Score:5, Insightful)
So if Mr. Astronaut became a lobbyist instead that'd be okay too? Or a Medal of Honor winner who pimps his heroism out to lobby for munitions makers seeking gov contracts? Guns and bombs is what he knows right?
But that's not what he's doing, now is it? He's starting a private company, with private investment, and creating what he hopes are practical solutions for other private industries and NASA.
This is exactly what I'm talking about -- "cynicism" is not saying "this will end badly" without concern for the specifics of what "this" is. You have to look at the actual reality and distinguish based on that. "So if he [did something else] that'd be okay too?", implying no distinction based on the actual activity or its outcome, is the opposite of realism.
For a self described cynic (as in always asking "who benefits?") you sure do have a idealistic outlook which goes against the weight of the evidence about who lobbys and for what.
He is going to benefit, obviously so, because he's the CEO of the company. What's the problem again? He's going to get a nice NASA contract, become Yet Another Defense Contractor, and lobby congress to give NASA more funds? Oh noes!
You don't sound like a cynic to me. You sound like a betrayed idealist, with a rosy-eyed view of how things "should" be, and constantly finding that not to be the case. So you say things will end badly in some vague way, without regard to what's actually happening because it doesn't matter.
Personally, seeing someone trying to use the 'best of both worlds' of private enterprise and government contracts to drag NASA kicking and screaming out of the 60s warms my cynical heart.
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Sense of reality = fail (Score:5, Insightful)
This is the same kind of math used by proponents of President Obama's healthcare socialization package. If you will, it's also the same math used to justify the Soviet command economy.
On paper, eliminating profits saves money for the hypothetical society. In reality, however, eliminating profit also eliminates self-interest, which very effectively stagnates or degrades the enterprise... be it at the level of a single supermarket, or the economy of the wealthiest country on Earth.
The reason why this doesn't work, is because you need several things to get something accomplished. You need the WILL to start it... the RESPONSIBILITY to see it through, and the MEANS to get it done. Socialism helps with the means... but not the will. Capitalism helps with the will, by accepting man as the egotistical bastard he is, and appealing to the basest of desires: greed.
But nothing helps with responsibility. For as long as clerks with 1-inch fingernails will 1-finger-type endless requisition forms to get anything done in large organizations (which includes companies as well as governments) with zero interest or concern for what they are doing, waste will reign supreme. At least in private enterprise, this is somewhat moderated by the need for more profit. A government bureaucracy, on the other hand, is like entropy. It spontaneously expands, and this can only be reversed locally, at an even greater cost to the entire system.
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Re: (Score:3, Insightful)
Spot the logical fallacy after I've corrected your basic error. With the technology to perform (unmanned) interplanetary missions and r
Re: (Score:3, Insightful)
Odds are, he's gone this route, because the current structure of the Federal government is such that it's much easier to fund and develop a project through a private corporation receiving federal funding than it is to have the agency to the actual work.
(This is nothing particularly new either. Although it's my understanding that NASA used to do more in-house engineering work than it currently does, rocket engines have been privately sourced since the days of Apollo, and possibly even earlier.)
He worked wit
Re:All that is keeping us from space is efficiency (Score:4, Interesting)
... a gallon of gasoline could potentially lift a human into orbit, less spaceship.
Actually it's quite a bit more than a gallon. (LEO is very high and very fast. Other orbits are moreso.) But the basic idea is sound.
Rockets are HORRIBLE energy-spenders. (Their big advantage is that they do work and are self-contained.) That's why there's all that work on various "space elevators", where you can use electric motors (or the equivalent), at efficiencies in the 75 to 98% range from electricity to kinetic energy, to move stuff from the ground to LEO, geosynch, or otherwise get it persistently off the ground and out of the atmosphere.
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