NASA's NEXT Ion Thruster Runs Five and a Half Years Nonstop To Set New Record

cylonlover writes "Last December, NASA's Evolutionary Xenon Thruster (NEXT) passed 43,000 hours of operation. But the advanced ion propulsion engine wasn't finished. On Monday, NASA announced that it has now operated for 48,000 hours, or five and a half years, setting a record for the longest test duration of any type of space propulsion system that will be hard to beat."

Comments

Perfect analogy for NASA

[Gothmolly]

Running your engines at full power but standing in one spot for 5 years. That pretty much sums up our space program since Apollo.

Re:Perfect analogy for NASA

[h4rr4r]

So then those rovers on Mars are figments of my imagination?

Our space program since Apollo has gotten better. Unless you think their is some scientific value in sending humans to play golf on other worlds.

Re:Perfect analogy for NASA

[fuzzyfuzzyfungus]

Would it be insufferably pedantic to mention Pioneer 10/11, Explorer 49, Mariner 10, Helios A/B(with Germany), Viking 1 and 2, Voyager 1 and 2, Pioneer Venus 1 and 2, ISEE-3(with EU), Magellan, Galileo, Hubble(with EU), Ulysses(with EU), Mars Observer, Clementine, WIND, NEAR Shoemaker, Mars Global Surveyor, Mars Pathfinder, ACE, Cassini-Huygens(with EU), Lunar Prospector, DS1, Stardust, Mars Odyssey, Genesis, Mars Exploration Rovers, MESSENGER, Deep Impact, Mars Reconnaissance Orbiter, New Horizons(in transit), STEREO, Pheonix, Dawn, Lunar Reconnaisance Orbiter, Solar Dynamics Observatory, Juno, GRAIL, Mars Science Laboratory, and Radiation Belt Storm Probes?

Sure, our man-in-a-can cred isn't what it used to be; but I, for one, welcome our robotic overlords.

Re:Perfect analogy for NASA

[Penguinisto]

Our space program since Apollo has gotten better. Unless you think their is some scientific value in sending humans to play golf on other worlds.

Laugh and minimize all you want, but the one geologist to land on the Moon managed to learn more (and faster) in his one short trip than all of the Mars rovers combined. Why, you ask? Because he didn't have to waste time looking at a picture and speculating on what a shadow or shape looked like it could be. Instead, he just walked up to an item of interest, looked at it, and was able to discern in seconds something that, well, takes teams of scientists weeks on end to speculate over nowadays.

...then there's that niggling fact that someday, space may be the only habitable home we have left after this one gets wrecked - be it by us or by the first asteroid that decides not to simply pass by. It would be nice to already have the tech to live there - preferably long before we're forced to learn it on a tight schedule.

Re:Perfect analogy for NASA

[Dyolf Knip]

Not really. The tools are impressive, but mostly in how they try to overcome the crippling need to run remotely from umpteen million miles away.

Let's have a look: http://en.wikipedia.org/wiki/Curiosity_(rover)#Instruments

Lists 14 instruments. But 5 of them are just cameras, strategically placed because they can't be moved. My friend the amateur photographer could do much better with her DSLR. The "environmental monitoring station" measures humidity, pressure, temperatures, wind speeds, and ultraviolet radiation; not exactly groundbreaking stuff here. Same with radiation assessment. There's a robotic arm capable of drilling holes a whopping 2" deep and a dust removal tool, commonly known as a 'broom'. The "Dynamic Albedo of Neutrons" sounds sexy as hell, but then you realize a person with a trowel could do the same job.

The other instruments are all spectrometers and a chromatograph. The means by which they work are novel, due to the aforementioned remote requirements, but the end result is not really different from what could be done in any decent lab 50 years ago. Honestly, a decent scientist with a shovel and a few thousand dollars in high school lab gear could do better than all the rovers ever sent. God help us if we ever needed a probe to do something _really_ difficult.

So by all means, send what probes are needed to figure out how to get people there, but anything beyond that will just provide minimal information at enormous cost.

Re:Perfect analogy for NASA

[Anonymous Coward]

...then there's that niggling fact that someday, space may be the only habitable home we have left after this one gets wrecked

Don't take offense, because I'm sure you're thinking this because you've been told so many times that this would be the case, but why is there the common belief that mankind would find a complete vacuum, devoid of ANY resources other than photons, be more suitable for our life than the Earth would be in any state of pollutive decay?

If we can build capsules for space, why not do the same thing here and protect ourselves from the elements? We can use space suits to travel around the exterior here, too, extracting useful resources from the fetid scum we created, and if we can shield ourselves from cosmic radiation, why wouldn't we be able to shield ourselves from any possible post-nuclear-holocaust radiation?

I'm certainly not suggesting that NASA is a waste of money - I am an aerospace engineer, after all - I'm just saying that if your house became infested with termites, you wouldn't resign yourself to abandoning it and living on a houseboat in the middle of the ocean because there are no termites in the middle of the ocean.

Re:Perfect analogy for NASA

[Sperbels]

He wasn't talking about Mars, but the moon. His argument stands.

No, he was walking about Mars. Quote: Not totally fair to say he couldn't find water, but Opportunity found it, while the geologist couldn't. Opportunity is a Mars rover. The geologist in question is Harrison Schmitt who went to the moon. He wasn't even looking for water...not that they put him in a place likely to have it. He was simply there to use his expert geologist eyes to find something geologically interesting, otherwise they would have just had one of their pilot astronauts grab some rocks. These aren't even comparable things. But I'm sure if you placed a geologist in the same spot Opportunity was, he could have found evidence for water in 30 minutes or less and spotted several other interesting things as well. Robots aren't adaptable to other kinds of missions. They do what they're designed for. A human can accomplish a multitude of things, adapt, and apply new knowledge on the spot. Yeah, robots cost a fraction of what it would take to put a human up there, a human can also accomplish far far more. But to argue that humans can't do more than a robot like the GP implied, is totally absurd.

Specific impulse

[abies]

I wonder if they had felt a specific impulse to switch it off?

Re:Specific impulse

[Impy the Impiuos Imp]

Nah. The lead scientist felt it was ok to let it run as long as they kept a close ion it.

Re:Too bad it's at NASA

[fuzzyfuzzyfungus]

Which all but guarantees that this engine will never do anything more.

Sort of like the ion thruster on the Dawn probe, which left Vesta about a year ago with an ETA on Ceres sometime in 2015?

Could we achieve 1G of thust.

[jellomizer]

My Hope if we could build a space craft that can accelerate 9.8m/s^2 (1g) for the duration of going to Mars and Back. You go to at 1g half way to mars, then you decelerate at 1g the other half. Orbit for a period of time. Drop down a landing party for a while. And go back at 1g half way decelerate at 1g the other half. Then you would have a good long range mission with out the 0g effect messing up the body.

Re:Could we achieve 1G of thust.

[Overzeetop]

Without relativistic effects about a year but, as noted by the sibling poster, relativity gets in the way from the outside observers point of view. And what good is next day delivery if the goods are 1 day old and the recipient's great, great, great, great, great granddaughter has to sign for the package?

Though practically impossible with current or proposed technology, it would, indeed, take only 35 days to reach 0.1c, and we'd be 225 million km from our starting point, ignoring gravitational effects of other bodies. Though in astronomical terms that's not very far (less than the diameter of Earth's orbit) - less than half way to Jupiter on the closest possible approach.

Fools!

[Anonymous Coward]

Running that engine for 5 years attached to the planet already caused a diversion of 0.01 on the orbit we have around the sun! That's why the sudden global warming! Tin foil ionic hat

Re:Fools!

[burisch_research]

Bzzt you are both wrong. The net acceleration due to this test is zero, because the ions ejected out of the engine are halted by the test chamber. Net result is zero force.

1G of thust - you're gonna need a bigger boat

[Overzeetop]

1G of thrust would require, as you mentioned, almost 10m/s2 of acceleration, or your mass x 10 in Newtons.

NEXT produces 236 mN of thrust at 7kW of power

A typical terrestrial nuclear power plant will produce about 1 GW of power, or enough to power 143,000 of these engines. That would result in 33,700 Newtons of thrust, able to accelerate a spacecraft at 1G weighing 3433kg.

To put that into perspective, those (143,000) engines would burn 2860kg/hr in fuel alone.

Re:Distance estimate

[abies]

Don't know where you got these numbers from, but:
- There is no way this ion engine can produce 0.3g acceleration on 2000kg probe; something is way off.
- in addition to propellant, ion engine requires power - a lot of power ; you need to add weight of nuclear reactor on top of that (which is probably only thing able to produce enough power for long term with small amount of consumable fuel); for 2000N you would need something like 50MW of constant power supply

But yes, if you can create imaginary engine giving you even 0.1g of constant acceleration for spaceship over period of few decades, entire galaxy is yours.

Re:How Fast?

[JTsyo]

F=ma
.236 N = 1000 kg * a
a = .000236 m/s^2

V=V0+a*t
V=(40,000 km/h)/(3600 sec/hr) + (.000236 m/s^2)*(50000 hours *3600 sec/hr)
V=53,591 m/s => 192928 km/hr =>0.00018 c