NASA Gives Solar Ionic Propulsion A Monster Boost (networkworld.com)

coondoggie quotes a report from Network World: NASA this week took a giant step toward using solar electric power for future space missions by awarding a $67 million contract to Aerojet Rocketdyne to develop an advanced electric propulsion system. Network World writes, "Specifically, Aerojet Rocketdyne will develop and deliver an integrated electric propulsion system -- known as the Advanced Electric Propulsion System (AEPS) -- consisting of a thruster, power processing unit (PPU), low-pressure xenon flow controller, and electrical harness. Such a system would deploy large solar arrays that can be used to convert sunlight into electrical power that ionizes atoms of xenon which is the propellant for the spacecraftâ(TM)s thrusters. In addition, such a power plant could potentially increase spaceflight fuel efficiency by 10 times over current chemical propulsion technology and more than double thrust capability compared to current electric propulsion systems, NASA said." NASA's plan is to use this propulsion system on its future Asteroid Redirect Mission, as well as on its mission to Mars.

Comments

What is a "spacecraftâ(TM)s thruster?"

[Anonymous Coward]

Well?

Re:'monster' ?

[Camel Pilot]

Monster is about the size of one Library of Congress

Worked one time for Rocketdyne on the SSME... started one month before the Challenger. Not good timing. Rocketdyne spent the next few months under suspicion as the cause for the accident. I help prepare a report to Richard Feynman during the investigation. I use to walk the executive corridors at lunch and marveled at some of the pictures on the walls of cool past research engines like Nerva a Nuclear powered engine and of course the massive Saturn 5 engines.

Re:'monster' ?

[fred911]

Monster as a qualifier cam be described as more than mondo and less than gianormous. Thanks for asking.

Monster Boost

[Anonymous Coward]

What, now even the rocket scientists at NASA are buying overpriced cables at Bsst Buy?

'10 times more efficient' and xenon gas

[kheldan]

I'd like to know how you can talk about a drive system being '10 times more efficient' when it's 'fuel' is one of the rarest gasses in Earth's atmosphere? Shall we just design a spacecraft drive system that uses giant diamonds or something instead, so it'd be cheaper and easier to obtain fuel?

Re:'10 times more efficient' and xenon gas

[ControlFreal]

It's all about delta-v, not about the occurence of said gasses on Earth.

Rockets work, whether we like it our not, according to the Tsiolkovsky rocket equation: the delta-v you can obtain it only logarithmic in your start mass / payload fraction, but linear in your exhaust velocity. That velocity is in ~3 km/s for chemical rockets, but 20-50 km/s for ion engines. That allows you to push a probe/ship from LEO into a transfer orbit using a massively lighter ship, which in turn allow you to launch that into orbit using a massively smaller launch vehicle.

Re:'10 times more efficient' and xenon gas

[LordWabbit2]

Well diamonds were perhaps a bad example, since we can make them now in such fine quality that it's almost impossible to distinguish from the real thing.

Re:'10 times more efficient' and xenon gas

[HeadSoft]

Ions Are Forever.

Re:'10 times more efficient' and xenon gas

[Anonymous Coward]

it's almost impossible to distinguish from the real thing.

Two things:
0. Lab created diamonds are REAL diamonds.
1. Even low quality lab created diamonds are usually MORE pure than the "real thing", and detecting the impurities and imperfections is how we identify the more expensive, poorer quality, naturally occurring diamonds (which may have cost some poor black peoples their lives).

"Oh, I love you so much I didn't buy a cheaper more pure and lab created Diamond, I made sure some African's blood was spilled for this more expensive naturally occurring diamond. This ring killed a nigger. Marry me."

Re:'10 times more efficient' and xenon gas

[Anonymous Coward]

Ten thousand Xenon nuclei, when all you need is an electron- isn't it ionic; don't you think? /ducks

Re:'10 times more efficient' and xenon gas

[Eloking]

I'd like to know how you can talk about a drive system being '10 times more efficient' when it's 'fuel' is one of the rarest gasses in Earth's atmosphere? Shall we just design a spacecraft drive system that uses giant diamonds or something instead, so it'd be cheaper and easier to obtain fuel?

Am I missing something extremely obvious or being "10 time more efficient" mean that we can use 10 time less of the said rare gas?

But why are we using Ionic propulsion system already? Well, because it is, AFAIK, by FAR the most efficient propulsion system in term of fuel weight/energy in use today.

But if you got an idea for an engine more efficient that a different and less rare fuel, I'm all ears. But it'll have to come before we start mining space and other planet (I've read that there's a lot of xenon in Jupiter's atmosphere?)

Re:'10 times more efficient' and xenon gas

[LWATCDR]

It uses a small about of Xeon I think the Dawn spacecraft used less than 500 grams for it's mission.

I am wondering if why we are not seeing these used on spysats. You could have then at a lower orbit if you used an ion engine to cancel out the additional drag.

Re:'10 times more efficient' and xenon gas

[LWATCDR]

I hate autocorrect Xenon.

Re:'10 times more efficient' and xenon gas

[kheldan]

Congratulations, AC, you're the only commentor in this thread that actually understands the question I was asking! 1E+6 Internets are awarded to you!

Being as unaware as I was about the quantity of said Xenon gas required in a typical application of this particular type of thruster, I assumed the quantity was significantly larger than I've now heard by at least an order of magnitude or two. Now that I have that information I see that it's not totally unrealistic.

Re:'10 times more efficient' and xenon gas

[Rei]

Xenon isn't used because it's a fundamental requirement - it's used because the cost of the fuel is basically irrelevant compared to the costs to launch it to orbit, and xenon provides (by a rather small margin) the best performance. But you can use all sorts of gases. You could use argon if you wanted and it wouldn't have much of an impact on performance. Even hydrogen is sometimes used.

Re:'10 times more efficient' and xenon gas

[Coren22]

I always assumed that the Mass of Xenon was the primary reason it was used. Is that not the case?

Speeding H^2 up to 40 km/s doesn't impart nearly the same momentum as Xe^2, though I suppose you could likely fit more H^2 on a spacecraft for the same volume/mass.

Cancel NASA!!

[Anonymous Coward]

I just bought a telescope on Amazon :P

PPU?

[Z80a]

Will it propel itself with 8x8, 2bit indexed color tiles?

Re:'monster' ?

[mukinrestak]

I'm more worried about the name "Monster Boost" itself. How the hell are we going to affords the trademark lawsuits from monster cables?

Clickbait

[justthinkit]

Clickbait article is clickbait.

Xenon drive has been around since the 1950s

The article's touted monster gain -- ten times better than chemical rockets -- is the same ten times gain NASA has been using in actually-launched-into-space rockets for years, if not tens of years.

The article talks about a $65M program to try to make even greater gains...and provides zero details. Probably because making "huge" gains in a technology that is over sixty years old ain't easy.

In summary, this article is about as interesting as GM announcing they are working to make fuel injectors ten times better than carburetors.

Re:Clickbait

[ceoyoyo]

Building an ion propulsion engine big enough to be used on a manned mission is a pretty big boost. Rocket engines have been used for a couple thousand years, but building one big enough to put humans into space was kind of a big development.

Re:Clickbait

[Rei]

For a long time it was assumed that nuclear was going to be the only realistic option for providing power to large ion engines. But the power / mass ratio on space solar has really been rising fast in recent years - look at ATK ultraflex / megaflex for examples. More and more, instead of rigid arrays, they're using unfoldable flexible arrays. They still have high cell efficiencies, but the masses are a tiny fraction of what they used to be.

Re:'monster' ?

[Applehu Akbar]

"Monster as a qualifier cam be described as more than mondo and less than gianormous. Thanks for asking."

Hopefully it's not 'monster' in the sense of 'cable'.

Re: why xenon gas

[Henarchaga]

I had the same question, and found the answer readily enough in layman's terms on wikipedia: https://en.wikipedia.org/wiki/....

It seems like there are three key reasons (which I am listing also in layman's terms):

1) As a "noble gas" xenon is typically inert, which reduces corrosion in storage and long-term usage as a thruster fuel
2) The gas can be stored in liquid form (more dense) at room temperature, unlike liquid oxygen or hydrogen, which makes it easier to transport and handle
3) It is far up enough on the periodic table that its electron shells can be excited with less energy input than other inert gases, making it more ideal for low-power
systems such as the solar panels that power the ion engine.

Bear in mind that I may be interpreting those wrong, but I do only have two years of university chemistry.

Re: why xenon gas

[kheldan]

I have zero years of chemistry classes; I've never taken one. Doesn't mean I can't understand the subject if you explain it to me.

Thank you for making an informative, non-sarcastic, non-pedantic comment in this thread. :-)