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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."
Running your engines at full power but standing in one spot for 5 years. That pretty much sums up our space program since Apollo.
I want to delete my account but Slashdot doesn't allow it.
I wonder if they had felt a specific impulse to switch it off?
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?
that is just cool...
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.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
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
If you had one of these on a spacecraft like Voyager with 1000kg of fuel running for 50,000 hours, what does that acceleration translate to in terms of velocity, assuming an initial velocity after launch of something like 40,000km/h?
the growth in cynicism and rebellion has not been without cause
So who's going out to attach this engine to the Dawn probe? Sounds like a one way trip.
So, if they had launched it into space, how fast would it be going after all this time? And would it still be receiving enough energy from the sun to maintain that level of thrust?
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
I think I've calculated this correctly - assume this was bolted to the back of a spaceship in 0g, and the whole unit weighed 2000kg and not accounting for weight decreasing over time as propellant burns, how far would you get? Assuming constant acceleration for the first half of the trip, constant slowing for the second.
7500kW = 2000N / a
a = 3.5m/s^2
t = 48000hrs / 2 = 86400000s
c = 299792458 m/s
d = (c^2/a) * (sqrt(1+(a*t/c)^2) - 1)
= 10794747340804852 = 1.14ly
So 1.14ly before you turn the thruster around to slow, and you've traveled 2.28ly after 5.5yrs.
Am I right? Does a career in space engineering beckon?
PS. What, STILL no Unicode in comments? Hi, Slashdot, it's been around for at least 20 years - move with the times, grandad.
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.
Is it just my observation, or are there way too many stupid people in the world?
All we need is two of those engines, a spherical cockpit, and two large solar panels attached to each side.
http://en.wikipedia.org/wiki/Dawn_(spacecraft)
It was launched in 2007 with an ion thruster.
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it's time for NASA to admit they locked the keys inside the thing, swallow their pride, and call AAA
how many pairs of boxer shorts should you own?
Tautologically speaking, I say this is redundant.
The ion thrusters on the Japanese Hayabusa asteroid sample-return mission kept on breaking down but after a lot of TLC the main spacecraft did get back to Earth and its sample capsule was recovered.
A European Space agency probe, the 370kg SMART 1 was powered by an ion motor and flew from Earth orbit to Lunar orbit under ion propulsion in 2004. It burned 80kg of fuel over about 13 months producing 68 mN of thrust.
wow. The fact that NASA has more interplanetary probes out there than all of the other nations combined, means nothing to you, eh?
NASA's been stymied by the neo-cons, BUT, that is about to change over the next 2 years. The neo-cons continue to pour money into the SLS, but it will not fly humans until 2022. OTOH, SpaceX will have their Falcon Heavy available at end of this year, or early next year. At that time, Musk is supposed to announce how much longer to develop the Dragon Rider (human rated launch capsule), and is saying that he will introduce information about MCT. MCT is what others of us know as BFR (big fucking rocket), but the new name is Mars Colonial Transport. if the inside info is to be believed, it will be ready by 2020, and will launch 150-200 tonnes, while the neo-con's SLS will take only 70 tonnes and will cost 3-5x the costs to launch.
So, I fully expect that NASA WILL get back on track, assuming that we can keep neo-con's dirty stinking paws off NASA for about 1 year or so.
I prefer the "u" in honour as it seems to be missing these days.
Seriously, we should put this on a small unit with solar cells and then attach this to the ISS. Better to put this to use, than having it sit there.
I prefer the "u" in honour as it seems to be missing these days.
wow. The fact that NASA has more interplanetary probes out there than all of the other nations combined, means nothing to you, eh?
NASA's been stymied by the neo-cons, BUT, that is about to change over the next 2 years. The neo-cons continue to pour money into the SLS, but it will not fly humans until 2022. OTOH, SpaceX will have their Falcon Heavy available at end of this year, or early next year. At that time, Musk is supposed to announce how much longer to develop the Dragon Rider (human rated launch capsule), and is saying that he will introduce information about MCT. MCT is what others of us know as BFR (big fucking rocket), but the new name is Mars Colonial Transport. if the inside info is to be believed, it will be ready by 2020, and will launch 150-200 tonnes, while the neo-con's SLS will take only 70 tonnes and will cost 3-5x the costs to launch.
So, I fully expect that NASA WILL get back on track, assuming that we can keep neo-con's dirty stinking paws off NASA for about 1 year or so.
Most of the space exploration done by the U.S. has been done on the watch of a Republican president, including all of the Apollo missions.
https://en.wikipedia.org/wiki/Timeline_of_Solar_System_exploration
http://en.wikipedia.org/wiki/List_of_Presidents_of_the_United_States
Also, Elon Musk is a registered independent, neither a Republican nor a Democrat:
http://en.wikipedia.org/wiki/Elon_Musk
You should also be aware that the backdrop for the majority of the space program was military, and based in the cold ware; when the U.S. lost their "best enemy" with the end of the cold war, that's when funding dried up, and that's when military contractor consolidation took a particularly big bite out of our technical capability with the demise of the DC-X program and the X-33 program.
It's unlikely that we are going to have cheap access to space any time soon, in any case, since as soon as someone can pull a John Travolta and buy a used SSTO spacecraft instead of a Boeing 707–138 is the day some idiot lofts a load of ceramic coated rebar and effectively ends up with the functional equivalent of a bunch of tactical nuclear weapons they can deorbit onto ground targets at will. Believe me, an Andy Griffith equivalent is not going to be launching a cement mixer body on top of a texaco gasoline tanker any time soon. Private launches will be heavily regulated for the foreseeable future.
If the Laws of Physics are getting in the way of scientific advances like this, then that's something we need to get Congress to take a hard look at in the coming years. /tic
from the protocols:
...
...
[quote]
Day 1500 09:00: still running within required parameters
Day 1500 10:00: still running within required parameters
[/quote]
Most of the space exploration done by the U.S. has been done on the watch of a Republican president, including all of the Apollo missions.
You mean like Apollo 1, 4-8, and all of the other tests and development that happened before Nixon came in in 1969? If you just wanted to use the launch dates, Carter seems to have done well with Voyager and Pioneer...
Or maybe it is just that there has been a steady stream of missions of various sizes, most of which were projects longer than a president's term, and Republicans have been in the White House more often than not between Apollo 11 and the Mars Rovers.
Yeah, Thomas Gold was right.
"Consensus" in science is _always_ a political construct.
Most of the space exploration done by the U.S. has been done on the watch of a Republican president, including all of the Apollo missions.
You mean like Apollo 1, 4-8, and all of the other tests and development that happened before Nixon came in in 1969? If you just wanted to use the launch dates, Carter seems to have done well with Voyager and Pioneer...
Or maybe it is just that there has been a steady stream of missions of various sizes, most of which were projects longer than a president's term, and Republicans have been in the White House more often than not between Apollo 11 and the Mars Rovers.
Kennedy was as much a hawk as anyone else when it came to the communists, including political assassinations in Vietnam, an attempted assassination of Castro, the Cuban missile crisis vs. the former Soviet Union, and the Bay of Pigs.
Make no mistake: Kennedy and Johnson don't qualify as what we think of today when we talk about Democrats.
And I guess development of Galileo and Magellan under Carter (well, latter scaled back under Reagan) don't count because he's not a "true Democrat" either. And the Mars rovers under Clinton don't count either, because he's not a true Democrat. ..
The largest change to NASA's budget after the spindown of the Apollo program during Johnson and Nixon's years, was the drop at the end Nixon's and Bush Sr.'s term, and the increase at the end of Carter's term, and under Clinton. Trying to correlate it with presidents makes a bunch of them look schizophrenic as several have both large increases and decreases. This should make it clear it is more about who is in Congress than the president. And in the last 20 years, it has been increasing under Democrats and decreasing under Republicans (although most of the time is flat either way...). If you go further back, you might as well credit all of the space race to a Democrat controlled Congress since they held onto it for such a long time, especially if you are going to credit Republicans (and pseudo-Democrats) for when they were in power for a long stretch.
Hmmm.
You really should check your history.
NASA was started under Eisenhower, and then massively funded under Kennedy/Johnson.
Nixon did massive cuts to it, and gave us the too expensive shuttle.
Carter was focused on energy crisis, economy, and rebuilding the military (quietly).
reagan spread NASA's mission all over, while not doing jack with funding.
Poppa Bush, a true republican, DID increase NASA's budget, but cut it in 4th year. In addition, he tried to get NASA focused.
Clinton did focus NASA, but in 1995, republican CONgress insisted that massive cuts come to NASA and that they be gutted. Clinton had us locked in with treaties on the ISS, that prevented republicans from gutting NASA more.
Under W, NASA was gutted again, and then had their money devoted to re-starting the shuttle, getting Constellation going, and providing a MINIMUM private space via COTS.
Under O, he has tried to up the money to NASA, and fully fund private space. However, the republican controlled house has actually cut NASA and has fought to kill private space, and have all NASA money devoted to SLS.
Look at those missions on the link and then click on them. You will find missions like voyager were started nearly a decade earlier. Lots of technology had to be developed. The Hubble was a good one. It was started by Carter, but cuts came under reagan and then challenger, delayed it until 1990. BTW, one major exception was clementine. IIRC, it was done in 4 years.
At this moment, the house republicans have continued to gut NASA, and push their money towards SLS. We have actually cut missions that we agreed to pay for. However, W's admin did not use treaties with Europe, so the missions were killed.
And having the launches watched, is not a big deal.
I prefer the "u" in honour as it seems to be missing these days.