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Electric Rockets Set To Transform Space Flight

Soulskill posted more than 2 years ago | from the flying-to-the-future-at-full-impulse dept.

Space 114

An anonymous reader sends this quote from an article at Txchnologist: "The spectacle of a booster rocket lifting off a launch pad atop a mass of brilliant flames and billowing smoke is an iconic image of the Space Age. Such powerful chemical rockets are needed to break the bonds of Earth's gravity and send spacecraft into orbit. But once a vehicle has progressed beyond low-earth orbit chemical rockets are not necessarily the best way to get around outer space. That's because chemical propulsion systems require such large quantities of fuel to generate high speeds, there is little room for payload. As a result rocket scientists are increasingly turning to electric rockets, which accelerate propellants out the back end using solar-powered electromagnetic fields rather than chemical reactions. The electric rockets use so much less propellant that the entire spacecraft can be much more compact, which enables them to scale down the original launch boosters."

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First electric post (5, Funny)

Spliffster (755587) | more than 2 years ago | (#39115859)

Tesla would love this shit!

Re:First electric post (1)

Chris Mattern (191822) | more than 2 years ago | (#39118491)

Tom Swift and his Electric Rocket!

Re:First electric post (1)

slick7 (1703596) | more than 2 years ago | (#39118771)

Tesla would love this shit!

Yeah, a gas powered flying saucer. How Edison of you.

Do we even have such a long cord? (1)

Anonymous Coward | more than 2 years ago | (#39115879)

Is there even enough material on Earth to produce a power cord long enough to propel a rocket to the moon!?

Re:Do we even have such a long cord? (4, Insightful)

decipher_saint (72686) | more than 2 years ago | (#39116085)

213 million six foot power strips daisy chained together...

Re:Do we even have such a long cord? (1)

hawguy (1600213) | more than 2 years ago | (#39116493)

213 million six foot power strips daisy chained together...

I've got three of them in a box under my desk that I can donate to the cause, so now you only need 212,999,997.

Re:Do we even have such a long cord? (0)

Baloroth (2370816) | more than 2 years ago | (#39116497)

Just watch out for any solar flares [xkcd.com]

Re:Do we even have such a long cord? (4, Funny)

ackthpt (218170) | more than 2 years ago | (#39116649)

213 million six foot power strips daisy chained together...

The Fire Marshall will have an absolute conniption fit over that one.

Re:Do we even have such a long cord? (1)

AliasMarlowe (1042386) | more than 2 years ago | (#39117229)

213 million six foot power strips daisy chained together...

The Fire Marshall will have an absolute conniption fit over that one.

Hah! Use the 12 foot versions and the conniptions will be halved... And halved again by using 20 foot single.outlet extension cords (not power bars). Problem solved!

Re:Do we even have such a long cord? (0)

Anonymous Coward | more than 2 years ago | (#39118533)

Thats great until some engineer forgets to throw the switch on one of the power strips, if your lucky they will be the lighted power button kind so its easier to tell where that one power strip is off.

Re:Do we even have such a long cord? (1)

TheInternetGuy (2006682) | more than 2 years ago | (#39118003)

Good sir, I believe you are completely wrong.

The article clearly states that the thrusters will be powered by solar energy!

As the distance to the sun is about 390 times the distance to the moon.

You would need something like 83 billion six foot power strips to reach the sun.

Re:Do we even have such a long cord? (3, Funny)

Ihmhi (1206036) | more than 2 years ago | (#39118839)

Yes, but knowing our government they'd buy them all from Belkin. Then we'd still have the iconic imagery of a trail of flame following the rocket up.

Re:Do we even have such a long cord? (1)

Ol Olsoc (1175323) | more than 2 years ago | (#39120185)

Then we'd still have the iconic imagery of a trail of flame following the rocket up.

Aw come on! Mod this guy up!

wait - how's this gonna work? (0)

winkydink (650484) | more than 2 years ago | (#39115883)

Aren't you going to need one humongous extension cord?

Re:wait - how's this gonna work? (1)

eternaldoctorwho (2563923) | more than 2 years ago | (#39115913)

Well, how else are you going to string this [wikipedia.org] up?

Space (0)

Anonymous Coward | more than 2 years ago | (#39115907)

Maybe this will mean a trip to the moo

Re:Space (2)

stevegee58 (1179505) | more than 2 years ago | (#39115941)

Or at least a meadow.
Mooooooooooooooooooooooooooo.

Ion Drive isn't new (5, Informative)

Anonymous Coward | more than 2 years ago | (#39115965)

This is old technology and the benefits of this have already been realized in many satellites. There is literature going back well over a decade documenting the trade space.

Re:Ion Drive isn't new (5, Informative)

Anonymous Coward | more than 2 years ago | (#39116301)

More like decades; quoted from Wikipedia,

The official father of the concept of electric propulsion is Konstantin Tsiolkovsky as he is the first to publish mention of the idea in 1911. However, the first documented instance where the possibility of electric propulsion is considered is found in Robert H. Goddard's handwritten notebook in an entry dated 6 September 1906. The first experiments with ion thrusters were carried out by Goddard at Clark University from 1916–1917.The technique was recommended for near-vacuum conditions at high altitude, but thrust was demonstrated with ionized air streams at atmospheric pressure. The idea appeared again in Hermann Oberth's "Wege zur Raumschiffahrt” (Ways to Spaceflight), published in 1923, where he explained his thoughts on the mass savings of electric propulsion, predicted its use in spacecraft propulsion and attitude control, and advocated electrostatic acceleration of charged gases.

A working ion thruster was built by Harold R. Kaufman in 1959 at the NASA Glenn Research Center facilities. It was similar to the general design of a gridded electrostatic ion thruster with mercury as its fuel. Suborbital tests of the engine followed during the 1960s and in 1964 the engine was sent into a suborbital flight aboard the Space Electric Rocket Test 1 (SERT 1). It successfully operated for the planned 31 minutes before falling back to Earth.

Re:Ion Drive isn't new (1)

ackthpt (218170) | more than 2 years ago | (#39116691)

Meanwhile I continue to listen to X Minus One and Dimension X radio shows and cannot believe any of this. Cleary it's all a hoax.

and also rocket jocks will be quarrelsome people with the attitudes of disgruntled mechanics and having flight or engineering credentials is a preposterous notion.

Re:Ion Drive isn't new (-1)

Anonymous Coward | more than 2 years ago | (#39116475)

Yes but we need at least one space story per day so the Space Nutters can mod each other's "we need to get off this rock" and "space mining" delusions up to +5 insightful.

Re:Ion Drive isn't new (1)

mug funky (910186) | more than 2 years ago | (#39118013)

you mad?

watch we don't send you INTO THE SUN!! HAAHA!

Re:Ion Drive isn't new (-1)

Anonymous Coward | more than 2 years ago | (#39118133)

I'm more sad than mad. Sad that otherwise rational, sane adults believe in adolescent fairy-tales. Hey, there are no problems here, just keep going, space will save us! How a total vacuum that only a handful of humans ever visited in fragile tin cans will save us from anything is a mystery. But we must believe!

The same website where geeks profess to be rational and anti-religion have the most irrational and quasi-religious delusions about space.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39118619)

I'm more sad

Yes, since you have to compulsively bring this up, regardless if a tech story is about space or not. Half the time you invent your own fake nutter posts just to have a straw man to fight, yet are always surprised when people call out the faked idiotic posts as idiotic. It is as if you have some delusion of nutters hiding behind every corner, while you are the lone voice of reason.

But that conspiracy mindset is not the saddest part. The sad part is you took a conspiracy mindset, and invented such a boring and pointless conspiracy to apply all of that energy to. If you must take up such a hobby, there are much grander, more entertaining conspiracy theories. Live a little, and worry about mind control chemicals in the water, Freemasons, reptilians, or Masonic reptilian mind control chemicals, instead of worrying about an occasional slashdotter having an impractical idea.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39119447)

I have NEVER invented a fake Space Nutter post. These lunatics give themselves PLENTY of rope, I don't need to do ANYTHING. The usual "we only have computers because of space" idiocy comes up regulalry. The Moon colony and space mining garbage pops up often enough, and there is PLENTY of "the SPECIES must get off this rock" tripe. I don't have TIME to make all that up!

But yes, I bookmark the most lunatic, delusional and fever-addled posts for reference, and laughs.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39120359)

Yes, NEVER [slashdot.org] , because capitalising makes it more true. Or maybe you don't remember because the nutters secretly erased your memory, while replacing your coffee with Folgers Crystals.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39120435)

Looks like the nutters are still trying to block your memory, and secretly mangled the URL of previous comment's link by dropping a digit. Correct link is here [slashdot.org] . They sure are a sneaky bunch, to be feared and fought with great effort.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39118663)

And that's why you always try to provoke them in every space related thread with your adolescent name calling?

Re:Ion Drive isn't new (1)

sycodon (149926) | more than 2 years ago | (#39116545)

Somebody do the math.

If you had a 100 megawatt reactor to play with on a ship, what kinds of velocity could you achieve?

Just for giggles, say it was one of the Shuttles and that you could>/i> fit a 100 megawatt reactor in the cargo bay.

Re:Ion Drive isn't new (4, Insightful)

tp1024 (2409684) | more than 2 years ago | (#39117303)

The watt count doesn't matter. It's exhaust velocity (more means more energy use, no matter what technology) of the engine and the total amount of energy carried by the reactor (more energy means more mass, means less speed). 0.1-1% of the speed of light should easily be possible, but I haven't done the math to the point of calculating multiple stages, optimizing the energy budget with respect to the trade-off between exhaust velocity and energy consumption and so on and so forth.

Hydrogen-Oxygen fuel has an exhaust velocity of about 4500m/s for a final speed on the order of 20km/s with multiple stages (for any significant payload). Simple ion engines can reach 30,000m/s, but final speeds will be less than expected, as the empty mass of the stages is higher. Something on the order of 100km/s with 2-3 stages should be possible. (Let's say 12,000 years to Alpha Centauri.) More sophisticated engines can reach up to 200,000m/s in exhaust velocity (2000 years to Alpha Centauri), but somewhere the energy limitations will kick in and I don't know whether before or after that point. (That's when the Uranium/Plutonium makes up a very significant part of the deadweight - even if you throw some of it over board in the process.)

Just build some of space ships and a couple of pyramids in a desert to remind people they are on their way.

Re:Ion Drive isn't new (1)

lgw (121541) | more than 2 years ago | (#39117523)

That looks very optimistic - do your number include stopping at Alpha Centauri, or jjust waving as you fly by at high speed? (And IIRC the total stored energy needed is immense, even at 200 km/s).

Re:Ion Drive isn't new (1)

rednip (186217) | more than 2 years ago | (#39117851)

do your number include stopping at Alpha Centauri, or jjust waving as you fly by at high speed?

Why wave, when you can just deceleration into it? Only four some odd years later we could tell what it was made of by just using a telescope. After all, it'll be kind of a useless trip unless you had some way of returning data.

Re:Ion Drive isn't new (4, Interesting)

tp1024 (2409684) | more than 2 years ago | (#39118161)

Nope, just getting there. Think of it as a beeping monument in the sky.

A beeping monument with telescopes. The main justification would need to be astrometry, which you could do a hell of a lot better if you had a good telescope several hundred or thousand AU away from earth. Currently, we're doing all our triangulation with a 2AU long base (twice the distance earth-sun). Using the same 29cm telescope as Hipparcos [wikipedia.org] , we could easily get 1000 times more accurate ranging data within mere decades.

It would be a revolution. True trigonometric measurements all the way to the other end of the galaxy, even the nearest neighboring galaxies, instead of the current guesswork based on guessing how bright a certain star is and thus how far it would need to be away in order to appear as bright as it does.

Re:Ion Drive isn't new (1)

tp1024 (2409684) | more than 2 years ago | (#39118517)

Just to add one more thing: The kinetic energy of a hypothetical 10t final stage is 2e14J, equivalent to complete fissioning of 3kg Uranium (of course, efficiency will not be 100%, more likely 0.1-1%).

Re:Ion Drive isn't new (1)

symbolset (646467) | more than 2 years ago | (#39120835)

The ion engines will get better over time. And there are quite a few problems with your math.

Re:Ion Drive isn't new (0)

Anonymous Coward | more than 2 years ago | (#39119153)

It's 1000 times too weak in its current state. The main engines of a Saturn V produced 55000 horsepower. 1 hp = 752 watts and it had 5 engines in stage 1. So, we need 200 Megawatts before this can be considered for a launch of that scale. Also, we either need a way to beam that power or an onboard nuclear reactor to make it happen. Btw, the capacity of the Saturn V was 50 tons to lunar orbit. With today's lightweight technology, that'd be an entire base.

Yes, BUT.... (2)

WindBourne (631190) | more than 2 years ago | (#39116629)

it was never incorporated into a tug. It has always been part of sats. With this approach, you will have a sat that can plug into a tug. The tug can be chemical, electric, or nuke (or combinations thereof). By separating the engine/fuel from the payload, it will mean that all we have to do is put something into LEO and then use a tug to move items around. A cargo load or a sat, can be done via electric. A human load, might get chemical to move up and around quickly.

Re:Ion Drive isn't new (1)

allcoolnameswheretak (1102727) | more than 2 years ago | (#39117575)

Satellites and starfighters. Twin Ion Engine Fighters have existed since 1977.

Ahh, the future (5, Interesting)

squidflakes (905524) | more than 2 years ago | (#39115997)

The best part about living where I live is that they are building VASMIR engines down the street. It would be a long walk, but I could still walk to a freaking starship drive factory.

Re:Ahh, the future (3, Funny)

gnick (1211984) | more than 2 years ago | (#39116423)

This is fantastic. Finally my ship will stop drifting backwards when I fire my ion cannons.

Re:Ahh, the future (1)

WindBourne (631190) | more than 2 years ago | (#39116659)

Oh, so you live in Costa Rica?

Re:Ahh, the future (0)

Anonymous Coward | more than 2 years ago | (#39116785)

Maybe he does.

Re:Ahh, the future (1)

WindBourne (631190) | more than 2 years ago | (#39116855)

Probably not. Many ppl in houston see the corporate HQ and think that is where the work is happening. It is not. It was outsourced. So, we pay a load of money to have NASA tech done out of the nation.

Re:Ahh, the future (0)

Anonymous Coward | more than 2 years ago | (#39116953)

But this is all for the *species*, right? Why bring your sad rock-based jingoism into this? For the glory of the SPECIES!

Re:Ahh, the future (0)

Anonymous Coward | more than 2 years ago | (#39118635)

If this is for the species, then how come America is the one paying for it all? Why bring your sad illogic into this?

Re:Ahh, the future (0)

Anonymous Coward | more than 2 years ago | (#39119555)

Because it's for the species. A thousand years from now, when humans will have colonized the entire Galaxy and will be spreading out to Andromeda in fossil-fuel powered tin cans, there will be legends and myths of the Great USA and how it financed the Great Species Leaving Of This Rock. There will be posters of Old Terra, with its useless "gravity" and "air" and "water", with glorious, GLORIOUS orbital colonies.

Don't you want to be remembered as the country that saved the human species from its odious fate to live on this mud ball, this rock, this planet? Who cares who pays for it! What small-minded concerns in the light of The Fate Of The SPECIES!

What don't you understand?

Re:Ahh, the future (4, Funny)

Tumbleweed (3706) | more than 2 years ago | (#39116963)

they are building VASMIR engines down the street. It would be a long walk, but ...

You may think that's a long walk, but that's peanuts compared to space.

Re:Ahh, the future (0)

Anonymous Coward | more than 2 years ago | (#39120137)

You live in Houston or Costa Rica ? I had the pleasure of working for H Kaufman in a company called CSC... Commonwealth Scientific Corp a few years ago here in Alexandria Va... He wore cowboy boots and bolo ties, sharp as hell too...

Er... isn't this an old idea? (0)

Anonymous Coward | more than 2 years ago | (#39116101)

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

Like the idea was thought up in 1911, first functioning one built in 1959...?

Proper tested in space in 1964 in the SERT-1 (http://en.wikipedia.org/wiki/SERT-1_%28spaceship%29)...

What's Next : Time Machine Set To Transform ? (0)

Anonymous Coward | more than 2 years ago | (#39116109)

( Very, VERY old . )

Transcontinental flight?

Zzzzzzzzzz.

Yours In Minsk,

Shiny sixties sci-fi retro fun (1)

ACK!! (10229) | more than 2 years ago | (#39116209)

We are going to get shiny metallic space suits next.
Robots that flails its arms screaming "Danger Will Robinson Danger !"
This is great stuff we are back to ION propulsion which is kind of cool. Remember the spaceships that sail like Solar wind and stuff?
That would be cool too. Perhaps next we can actually get someone to care and fund this stuff and some of it will end up actually mattering in the long run.

Re:Shiny sixties sci-fi retro fun (3, Insightful)

Tumbleweed (3706) | more than 2 years ago | (#39116979)

We are going to get shiny metallic space suits next.
Robots that flails its arms screaming "Danger Will Robinson Danger !"
This is great stuff we are back to ION propulsion which is kind of cool. Remember the spaceships that sail like Solar wind and stuff?
That would be cool too. Perhaps next we can actually get someone to care and fund this stuff and some of it will end up actually mattering in the long run.

Of all the things in your posting, the last sentence is by far the least-likely. :(

Oh course you can. But ... (1)

Anonymous Coward | more than 2 years ago | (#39116227)

Well, it's still a lot of fluff. Yes, you can create an electric propulsion system that over a long period of time can absorb enough energy to move an object. But should the object need to change direction these drives may take weeks to change a ships direction by 10-20 degrees. If you are thinking of sending people up in a ship that can't has such limited mobility you might as well give the passengers their last rites before lift off.

For each and every action there is an opposite reaction. While jettisoning 100lbs out the back of a rocket the mass is constant and the reaction is limited. Chemical reactions are used because 1. They give more energy output per pound of weight. 2. They give out energy in the quickest period of time. So you can have an ion drive but without additional engines it will take years to accelerate and decelerate.

Re:Oh course you can. But ... (3, Informative)

stjobe (78285) | more than 2 years ago | (#39116779)

Yeah. Dawn's ion engines (linked to in TFS) have a very high ISP (3100s), but an equally low thrust (90 mN).
As a comparison, the F-1 engines on the Saturn V Stage I-C had pretty low ISP (about 250s), but a massive 34 MN of thrust.

Basically you can have high ISP (electrical) or high thrust (chemical), but not both.

Unless you go VASIMR, of course, and we're not quite there yet.

OT: Rocket Scientists Are Not Scientists (3, Insightful)

iliketrash (624051) | more than 2 years ago | (#39116257)

This piece piques one of my pet peeves, the confusion between scientists and engineers. Scientists do not build rockets--engineers build rockets. Even if a person trained in, say, physics, is designing a rocket, that person is effectively acting as an engineer.

I object to attempts to glorify certain kinds of engineers by calling them scientists. There is no such need to glorify engineers--they are glorious in their own right. Calling them scientists is a slap in the face and an insult.

Engineering and science could hardly be different. Engineers put things together; scientists take things apart.

Re:OT: Rocket Scientists Are Not Scientists (2)

Spy Handler (822350) | more than 2 years ago | (#39116443)

You're right, calling those lowly aerospace guys "rocket scientists" is an affront to real scientists everywhere.

-Mike Q. Hunt, computer scientist
Java, C#, Ruby project leader

Re:OT: Rocket Scientists Are Not Scientists (1)

Anonymous Coward | more than 2 years ago | (#39116679)

Yeah, No. In practice engineering and science go hand in hand. "Rocket scientists" or aerospace engineers indeed had/have to learn and understand new physics and create knowledge with the scientific method to engineer/build new devices. Scientists in the lab frequently have to apply their science and engineer measurement tools and facilities to approach new science. A PhD dissertation in mechanical engineering a scientific and an engineering contribution.

Re:OT: Rocket Scientists Are Not Scientists (2)

Whatanut (203397) | more than 2 years ago | (#39116803)

Of course, I would argue that engineers don't typically build rockets either. They design them. Then some factory worker builds it...

Re:OT: Rocket Scientists Are Not Scientists (0)

Anonymous Coward | more than 2 years ago | (#39117005)

I know plenty of engineers that design and build (hands on) spacecraft.

Re:OT: Rocket Scientists Are Not Scientists (0)

Anonymous Coward | more than 2 years ago | (#39117141)

Yes calling true engineer a scientist is slap in the face and an insult.

Scientists use imagination, engineers use creativity.
Scientists merely discover things that already exist, engineers create new things from things that exist.

As a result...

Engineers need to use theory to predict the result in the real world, scientist merely use the real world to validate the approximation proposed by their theory.
Engineers need to account for defects in the scientific model in the real world, scientists merely attribute defects in a model as "noise" until confronted with new evidence.

Of course engineers couldn't do their work in the real world w/o being scientific, but scientists often do their work w/o being realistic. ;^)

Re:OT: Rocket Scientists Are Not Scientists (1)

Nefarious Wheel (628136) | more than 2 years ago | (#39118451)

Scientists use imagination, engineers use creativity.

Scientists find out stuff, engineers figure out stuff.

Re:OT: Rocket Scientists Are Not Scientists (5, Insightful)

ceoyoyo (59147) | more than 2 years ago | (#39117183)

If you're building new drives to experiment with, you're a scientist. If you're following established principles to build a drive then you're an engineer.

The distinction isn't nearly as clear as you imply, and isn't based on your criteria.

I have degrees in oth science and engineering. Normally I do science with a bit of engineering, figuring out how to do new things. Sometimes I do engineering with a smattering of science figuring out how to do those new things out in the field.

Re:OT: Rocket Scientists Are Not Scientists (1)

BryanL (93656) | more than 2 years ago | (#39117243)

Is that you Sheldon Cooper?

Re:OT: Rocket Scientists Are Not Scientists (0)

Anonymous Coward | more than 2 years ago | (#39117253)

I would put it another way, scientists deal with theory, engineers deal with reality.

Re:OT: Rocket Scientists Are Not Scientists (0)

Anonymous Coward | more than 2 years ago | (#39117339)

I've worked with, in and around rockets my entire career. I've worked with Phd engineers, physicists, computer scientists. Most of the work is done interchangeably regardless of the job title.

Re:OT: Rocket Scientists Are Not Scientists (0)

Anonymous Coward | more than 2 years ago | (#39117531)

Engineering and science could hardly be different. Engineers put things together; scientists take things apart.

Wouldn't that mean scientists reverse-engineer:?

Surprised RTG powered probes dont use this. (4, Interesting)

wisebabo (638845) | more than 2 years ago | (#39116261)

I've actually been following ion powered (and all space flight) for a long time now and have wondered that ever since Deep Space 1 (no, not a TV series) "proved" the technology worked (that was one of its main jobs, it was a technology demonstrator) they didn't use ion engines on the space craft that used RTGs.

In particular New Horizons has travelled billions of miles coasting to Pluto, 99% of the time in hibernation despite the fact that its plutonium powered RTG is generating electricity whether used or not (it's not a reactor, it is always "on"). Considering the distance it has to travel, an ion drive could've really sped things up (or conversely allowed it to brake, and orbit Pluto!). Cassini might not have been such a good choice because maybe having the drive on doesn't allow good scientific observations (Cassini doesn't have its instruments on a scan tilt platform) and anyway the many delta - V changes might have required more thrust than the very weak ion drives can provide.

Actually, maybe ANY probe headed further than the moon or mars would find this useful. Juno, the Jupiter orbiter had huge solar panels which, during the cruise phase could have powered a decent ion engine. Messenger, the Mercury orbiter, although not going "far", had a huge delta-V requirement and had access to plenty of solar power.

Oh well, at least more and more probes like DAWN use this. I would presume when we return to the outer planets with any really ambitious probes (Europa lander/sub, Titan balloon/boat) they'll use this.

Someday, when we talk about sample return missions and the delta-V requirements at least double (and the fuel requirements go up geoemetrically!), ion drives (or their derivatives like the Vasimir drive) will be essential.

Since you liked the previous comment... (1)

wisebabo (638845) | more than 2 years ago | (#39117269)

How about this; NASA should equip the upcoming 8 BILLION DOLLAR JWST with an ion drive. And put a little extra xenon fuel in the tank!

That way, if something should go wrong with the 8 BILLION DOLLAR spacecraft, there's at least a small chance we'd be able to bring it back to LEO where it could be fixed (like Hubble). We won't have man-rated capability to fix it where it is for probably for another decade. :(

Actually since it's probably way too late to add an ion drive and fuel tank to this thing, why not at least put on some "hard points" so that something could grapple with it without damaging it? We should also develop a space tug, like the one the Swiss (of all people) are doing to de-orbit space junk; but bigger, more powerful and able to go out into deep space (radiation hardened, big fuel tanks). That, combined with tele-operated robots could be very useful. Like when we want to upgrade this thing's optics or instruments (like was done on Hubble several times). I think it's safe to say that sensor technology will likely improve substantially during this thing's lifetime (if it hasn't already!)

These single, super expensive probes (Curiosity, I'm looking at you too!) might be the only way to push back the frontiers of science and technology but they are very scary from a risk management perspective. We're not as rich as we used to be. :(

Re:Surprised RTG powered probes dont use this. (2)

DerekLyons (302214) | more than 2 years ago | (#39117977)

I've actually been following ion powered (and all space flight) for a long time now and have wondered that ever since Deep Space 1 (no, not a TV series) "proved" the technology worked (that was one of its main jobs, it was a technology demonstrator) they didn't use ion engines on the space craft that used RTGs.

Because ion drives are heavy, and their fuel tanks are heavier - and the wiring and controls are complex. So, weight to take away from payload, and more things to break, for very little return. What's not to like?
 

Considering the distance it has to travel, an ion drive could've really sped things up (or conversely allowed it to brake, and orbit Pluto!)

Nope. While ion drives have insanely high ISP's, they have almost no thrust. And it's thrust you want for braking into orbit, especially for small bodies like Pluto. (And that's on top of the whole "the drive and it's fuel would replace 90% of the payload" problem.)
 

Someday, when we talk about sample return missions and the delta-V requirements at least double (and the fuel requirements go up geoemetrically!), ion drives (or their derivatives like the Vasimir drive) will be essential.

Before that can take place- two things need to happen. The first is a power supply vastly more efficient and more powerful than pretty much anything built to date has to be invented, and has be light enough to not eat up significant payload. The second is someone needs to develop an ion drive (or derivative) that works worth a damn with much lighter fuels than they currently do. Then, and only then, will ion engines (or derivatives) stop being a solution in search of problem.
 
But until then, scientists and engineers in need of funding will keep beating the drum of our wonderful ion powered future - only a few years off. (Just like it has been since the 50's.)

already widely used (2)

recharged95 (782975) | more than 2 years ago | (#39116267)

The HS601 and its XIPS system [daviddarling.info] is technically electric since it is an Ion propulsive device. The above FTA is more about plasma thrust, but again all these concepts have been around for 50yrs: it's well known higher specific impulse == more acceleration for space flight == a better engine (and ions have more impulse than anything chemical)...

Thought it was about VASIMR. (3, Informative)

Loadmaster (720754) | more than 2 years ago | (#39116275)

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

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

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

Re:Thought it was about VASIMR. (4, Interesting)

Spy Handler (822350) | more than 2 years ago | (#39116601)

I guess what I'm saying is he isn't a crank.

Actually, according to Rob Zubrin of Mars Society, he is one. The technology itself isn't a crank, it's real, but his claims (going to Mars in 39 days) and the big bucks he's soliciting are quite cranky.

To do what he's claiming, you would need to hook up the VASIMIR to a huge nuclear reactor. How do you get that reactor into orbit? You can't, not without a Nova type rocket bigger than a Saturn V. But if you had such a rocket, you could just blast off to Mars the old-fashioned way.

His other proposal is coupling a fusion reactor (which should be lighter than an equivalent fission one) to the VASIMIR. Well as we all know, fusion is always 20 years in the future.

Re:Thought it was about VASIMR. (2, Interesting)

WindBourne (631190) | more than 2 years ago | (#39116821)

Getting the reactor into space is NOT a big deal. The issue with VASIMR is that you need LOADS of electricity. As such, it would weigh so much that VASIMR would not be able to push it around. And that is a reactor without ANY shielding. The issue is that the radiator to dump heat would weigh a great deal.

It is far more likely that we will send a team on a one-way mission to Mars and keep them there for 10-20 years, while we re-develop NERVA. NERVA makes far more sense for moving around the solar system then does a VASIMR/fission reactors.

I will say that VASIMR will make great sense once we do fusion that generates electricity directly (IOW, beta- emissions only).

Re:Thought it was about VASIMR. (0)

Anonymous Coward | more than 2 years ago | (#39118531)

I will say that VASIMR will make great sense once we do fusion that generates electricity directly (IOW, beta- emissions only).

I think ionised He4 is a more likely prospect.

Re:Thought it was about VASIMR. (1)

rgbrenner (317308) | more than 2 years ago | (#39120053)

while we re-develop NERVA. NERVA makes far more sense for moving around the solar system

Nerva [wikipedia.org] ? The roman emperor from 96-98? He's able to move things around space? Cool. Did not know that.

Re:Thought it was about VASIMR. (2)

WindBourne (631190) | more than 2 years ago | (#39120869)

Here. [wikipedia.org] and here. [wikipedia.org]

Re:Thought it was about VASIMR. (1)

DerekLyons (302214) | more than 2 years ago | (#39118031)

I guess what I'm saying is he isn't a crank.

Actually, according to Rob Zubrin of Mars Society, he is one.

And to be considered a crank by Robert Zubrin (a World Class Crank himself), you really have to be whack-a-doodle.

Like the Ion engines in Star Wars? (0)

Anonymous Coward | more than 2 years ago | (#39116309)

Cool!

Space Age 2 (1)

sexconker (1179573) | more than 2 years ago | (#39116325)

Space Age 2: Electric Boogaloo.

Re:Space Age 2 (1)

youn (1516637) | more than 2 years ago | (#39116997)

Space age with a squirrel in spacesuit looking going after the space nut, causing mischief throughout... now that sounds like a fun sequel to ice age :)

Old news (1)

spectral7 (2030164) | more than 2 years ago | (#39116343)

SEP has been in regular use for over a decade now...first EP-powered deep space mission was in 1998 (Deep Space 1), and just about every Earth-orbiting satellite relies on EP.

Re:Old news (1)

Brett Buck (811747) | more than 2 years ago | (#39116465)

I agree that it is old new, but most Earth-orbiting satellites DO NOT have anything like electrical propulsion.

They've ALREADY transformed space flight (2)

QuantumHack (58048) | more than 2 years ago | (#39116345)

I built an ion rocket in 6th grade that was suspended from a string, and would increase the height to which it swung every time the high-voltage transformer was pulsed. Deep Space One had an electric rocket. These have been around awhile.

Take us out... (0)

Anonymous Coward | more than 2 years ago | (#39116375)

1/4 Impulse power Mr. Sulu...

Captain Kirk of the USS Prius (3, Funny)

Oswald McWeany (2428506) | more than 2 years ago | (#39116483)

Stardate 45280.4

My crew and I have just left Earth's orbit, it took a mere 15 minutes to accelerate enough to reach escape velocity. Unfortunately, we ran out of batteries the moment we passed the moon and are now waiting for the Vulcans to come rescue us. Unfortunately, there are no electric charding stations out past the great-divide so we will have to be taken back earth where our crew will double the number of lithium ion batteries.

Why don't they... (-1)

Anonymous Coward | more than 2 years ago | (#39116487)

Use nuclear power with these things? Or is that a stupid idea?

I mean, you could just dump the waste over Russia and France...

Not only used on US missions (3, Insightful)

Trapezium Artist (919330) | more than 2 years ago | (#39116495)

I've long since given up on there being any semblance of proper research done in such articles, particularly when a nod might have to be given to anyone outside the US.

I'm no expert in the history of solar electric ion propulsion systems, but believe that NASA's Deep Space-1 mission in 1998 was (I think) the first to use SEP as its primary post-launch propulsion, as several subsequent NASA missions, including Dawn, as discussed in the article.

However, several European Space Agency missions have also used similar systems, including the ARTEMIS satellite in 2001 to get itself to geostationary orbit, the SMART-1 mission to the Moon (launched 2003, ended in a deliberate crash onto the Moon in 2006), the GOCE gravity-mapping mission, and the BepiColombo mission to Mercury (due for launch in 3 years) will be using one. The Japanese Hayabusa-1 asteroid sample return mission also used one.

Just trying to set the record at least a little straighter ...

Forget ion or VASIMR (2)

WindBourne (631190) | more than 2 years ago | (#39116539)

A better approach is the Electrodynamic tether [wikipedia.org] . Basically, create a linear motor against the earth's mangnetic field. This can only be used in orbit, BUT, there would be no fuel.

Nice but fairly useless (1)

Cyberax (705495) | more than 2 years ago | (#39116579)

All the electric propulsion methods have thrust in the order of Newtons. That's usually enough for interplanetary cruises but doesn't solve the most important problem - putting things into the orbit.

Re:Nice but fairly useless (1)

Dasher42 (514179) | more than 2 years ago | (#39116971)

Wouldn't balloons or maglev catapults be good alternatives for first stage boosters? Both would feature considerably less energy input.

Re:Nice but fairly useless (1)

Cyberax (705495) | more than 2 years ago | (#39117091)

Nope. Maglev catapults need to be of stupendous size to be useful and balloons are not useful at all.

"Solar powered" is a sham (0)

Anonymous Coward | more than 2 years ago | (#39116667)

To get decent acceleration on these things, like VASIMR, the power requirements are far higher than what can be reasonably accomplished with solar. If we wanted to use one of these to explore the outer solar system (manned or unmanned), where it makes the most sense, its so far away from the sun that solar energy density drops to just a few watts per square meter.

If we wanted to go to Mars, Nuclear Thermal Rockets are a better choice. Either way nuclear energy will be the foundation of true interplanetary spacecraft.

Many of you are missing the point (2)

WindBourne (631190) | more than 2 years ago | (#39116675)

This is not about creating an electric engine. It is about creating a TUG or Tractor that is electric powered. With such a device, it would be cheap to put a load into GEO or to EML1 cheaply.

Electric Rockets Really? (0)

g0bshiTe (596213) | more than 2 years ago | (#39116711)

I mean cause everyone knows weight is a factor when lifting objects into orbit, so no doubt batteries to power the engines wouldn't be a factor.

Re:Electric Rockets Really? (0)

Anonymous Coward | more than 2 years ago | (#39116985)

-1 moron

Re:Electric Rockets Really? (2)

buback (144189) | more than 2 years ago | (#39117051)

Electric engines would either use solar panels or RTG for power, not batteries. Hell, they'd use fuel cells before they used batteries. any of these options are much much lighter than normal fuel, but even if they were equal for certain sized payloads, electric engines are much more efficient, so as payload mass increases, fuel mass scales at a much smaller rate.

Watch it! (1)

Grindalf (1089511) | more than 2 years ago | (#39117077)

Watch that the electrostatics don't go near the cryo O2 H2 launch propellant tanks, they go off with quite a bang!

Cool, but huh? (1)

jamessnell (857336) | more than 2 years ago | (#39117589)

This is about Ion drives right? Sounds like it.. There are probes/satellites out there that have ion drives - they were conceived of in something like the 1960s. Not exactly news, but indeed it is awesome. Though Ion drives don't produce the necessary thrust to be used for atomopheric travel. But one can hope.

Electric Rockets story and no mention of Lifters? (0)

Anonymous Coward | more than 2 years ago | (#39117711)

Which have been found to work in a vacuum [jnaudin.free.fr] .

Furthermore, those "tests" done by some that "prove" a lifter doesn't work in a vacuum are as flawed and absurd as a test of a car being driven into deep water and upon being found not to work, being declared by engineers that this "proves" internal combustion engines (ICE) don't work underwater.

Well one of the central features of an ICE is combustion and water getting into such an engine prevents that.

As for how this relates to lifters, it's as such: A lifter is composed of 3 main parts, a dielectric, and two asymmetrical conductors. Now virtually all lifters to date have been constructed using air as the dielectric, therefore when a lifter is placed in a vacuum it won't function as one part of it is missing, which in this case is the dielectric.

This is of course not because the lifter doesn't work in a vacuum anymore than an ICE can't work underwater. When an ICE is protected as it is in a submarine it works perfectly well and when a lifter has a solid dielectric like plastic instead of air it works in a vacuum [jnaudin.free.fr] .

Hopefully experimentalists take note of this fact and work to bring this highly useful technology to society.

Re:Electric Rockets story and no mention of Lifter (1)

Electricity Likes Me (1098643) | more than 2 years ago | (#39119839)

You do realize the dielectric constant of vacuum vs air is pretty much exactly the same? A handy chart. [wikipedia.org]

More importantly, that web site you linked to notes that thrust in a vacuum is greatly reduced. Gee, I wonder why that could be - could it be because it's not actually a perfect vacuum, and thus there's still some medium for lifter to accelerate against?

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