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back to article Real sci-fi space ships coming at last? NASA tests nuclear engine

NASA has conducted tests of a nuclear reactor intended to generate electricity in space for the first time since 1965, offering hope that humanity may now belatedly get serious about building proper, powerful spaceships of the sort long envisaged in science fiction. The space agency has just announced the tests, conducted by …

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Next SPB project?

Once LOHAN has reached her climax, could the geniuses at the SPB perhaps look at developing a full-fledged nuclear-powered launch vehicle. It can't be that difficult...

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Orion...

Good ol' bang bang...

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Happy

Re: Orion...

Dammit. I came on here specifically to ask when they were going to build an Orion. :o)

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Coat

"That's not even enough to heat up a kettle..."

Scotty? Put the tea on.

The engines cannae tak it Cap'n.....

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Re: "That's not even enough to heat up a kettle..."

That's the reason for the lack of any British space missions - in space no one can hear you say "fancy a cuppa?"

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Headmaster

Re: "That's not even enough to heat up a kettle..."

Of course one kilowatt of electricity can heat up a kettle. Granted, you won't be getting a nice steaming cuppa in time for elevenses, but the kettle will get slightly hotter.

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Re: "That's not even enough to heat up a kettle..."

Sorry Martin, 1Kw for a couple of minutes will boil a kettle. The insignificant Kelvin metric anomaly matters to all who dunk...

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When can I buy one for home use?

More reliable than Solar or Wind power, and with the feed in tarriff, I could sell most of the daytime power back to the grid and probably make a profit

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you could have 6mw with a perpetual dynamo generator powered by the electric motor instead of wind

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Oh, and violate the Law of Conservation of Energy? Where does the energy come from?

Anyway, the DUFF doesn't answer one very important question, and one which has likely stymied all non-chemical rockets for decades: What are you gonna use for reaction mass? To date, we've yet to develop anything resembling sci-fi's pure-energy propulsion, as there remains the infamous "underpants gnomes" step (IOW, ?????). How do you convert the electrical energy into kinetic energy? The only we know how is electromagnetic propulsion, and THAT requires a reaction mass. Furthermore, if Newton has anything to say about, it's gonna either a lot of mass OR a lot of energy (probably somewhere in between) to accelerate and decelerate a manned spacecraft to and from any reasonable fraction of c.

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i said it all a million times,.

6mw from 20 rpm = 300,000 watts from every full rotation when a dynamo is at maximum output, a electric motor will not use 300,000 watts to power it as watts = electro magnetic calibration, the everyday common motor is either

high RPM and low torque or low RPM and high torque, to turn a dynamo is low RPM and low torque with a motor calibrated specific to the dynamo

you just use a solar battery cell to start them up or the national grid

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Stop

Reaction mass? We don't need no steenkin' reaction mass!

http://emdrive.com/

Slow, but steady, and a neat hack (if it works as advertised).

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"i said it all a million times,."

So build one !

Bet you can't !

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Re: "i said it all a million times,."

im a looser and dont have £1000 for a 1+ kw wind turbine with full battery and transformer, and a good regulator to control the watts to the motor that is not made for its use you get from a industrial electricians shops made for a factor machine or power drill

the input watts to the dynamos battery is that of the RPM output, you just loop back in a primitive setup 90 watts, and have the rest being stored in the battery on every full rotation

if you have 300,000 watts from every full dynamo rotation, and the motor used 1kw for every of its RPM, you still have 299,000 watts to power the battery or full circuit grid

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Facepalm

Re: "i said it all a million times,."

Nanos? Is that you? (One for the CIXen.)

Seriously, Dude - put your analyst on danger money.

GJC

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Re: Reaction mass? We don't need no steenkin' reaction mass!

But terribly inefficient. 2.5kW yields .72N of force at current rates. So the ability to accelerate in vacuum an object about the mass of a fifth of liquor 1 m per second per second. Plus I have to wonder about its usefulness in atmosphere. So, looks like it's back to waiting.

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Trollface

Re: "i said it all a million times,."

You must have, you gotta gold badge.

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Re: "i said it all a million times,."

You Sir are a troll or sadly lacking in even the basics of a scientific education.

Seriously try http://en.wikipedia.org/wiki/Perpetual_motion as a primer

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Re: "i said it all a million times,."

if you want to power a spaceship, you just need your everyday domestic wind turbine kit you will have in your loft, and a power drill motor to turn the direct drive dynamo instead of the wind, a power drill motor has plenty of extra RPM and torque then you actually need and can give you a constant 10kw with ease

if you put it all in a cylinder, the battery just becomes a battery cell, you can replace and charge up using solar power, and can power mars and every thing else

you can make find farms worth while, or just make massive turbines the size of houses, its all just math, AC and volts, once you know the torque the dynamo needs at its maximum output RPM

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Re: "i said it all a million times,."

he'll have it hooked up to the washing machine before you can say spin cycle.

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Re: "i said it all a million times,."

"if you want to power a spaceship, you just need your everyday domestic wind turbine kit you will have in your loft, and a power drill motor to turn the direct drive dynamo instead of the wind,"

That'd be a troll then - there IS an icon you know

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Re: "i said it all a million times,."

the space shuttle size craft would only need 10kw, if you want a settlement on mars you can happily start off with 1 or 2 MW, for lights of planets, and making oxygen if a good source of water is found like nuclear submarines

domestic kits include the wind turbine, that generates the electric, the electric gets stored in a battery, the electric stored in the battery goes through a transformer, before it reaches you house circuit for your green power use

you can put it all in a 2 litre trash can size cylinder, if you have a motor on top driving the direct drive dynamo

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Re: "i said it all a million times,."

1 or 2 MW, for lights of plants, plants would take years to grow on mars without aload of ultraviolets, and no body would choose to live on mars without onion rings and a salad sandwich

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Re: "i said it all a million times,."

ZModem.

I think I see where you're coming from, but it's utterly wrong. You've seen a 2MW generator and thought "hey, if I spin that shaft I'll get 2MW!" then thought "Hey, you know what spins really well? An electric motor."

Unfortunately the electric motor will have to put more than 2MW of power into the dynamo to get 2MW of power from it. This is because as you spin the rotor of the dynamo the resistance to movement builds up more and more; spinning the dynamo shaft inside the coils of the dynamo creates a magnetic field which acts against the motor you're using to drive the dynamo shaft. You can't get rid of this field; it is this magnetic field growing and collapsing that pushes the electrons through the wire and so creates an electrical current.The faster you spin it the more resistance there is.

If you think you can do it, build a smaller model. Even a model that produces no excess power but spins itself forever would be worth approximately all of the money in the world. You would become an overnight billionaire, worth substantially more than the oil companies who'd really not like you (but to whom you would pose little immediate threat). Maplin or RS (or even eBay!) would be able to provide you with an appropriate motor, dynamo and other components to give it a go.

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Boffin

Re: Reaction mass? We don't need no steenkin' reaction mass!

> But terribly inefficient. 2.5kW yields .72N of force at current rates.

Presumably though if you were already going 3km/s and it was still producing .72N, it would be near on 100% efficient?

It's not hard to reach those speeds either, if you're in a vacuum and prepared to wait. A probe en rourte to Pluto was said to be going 22km/s in 2006.

http://www.newscientist.com/article/dn8587-pluto-probe-set-to-break-speed-records.html

Which of course raises the question: How does the efficiency drop off with speed? If there's no mass ejection, it shouldn't?

But then past 3.5km/s it would be >100% efficient?

That alone makes it seem to me like it's not going to work, sadly.

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Re: "i said it all a million times,."

electric motors do not have shaft power and why they are the only kind of motor that can turn massive axles, and why aircraft carriers need to be nuclear, while all other ships use diesle generators

the input watt powers the electro magnets, the calibration while depend on what

the motors RPM and torque is

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Re: "i said it all a million times,."

you can generate a constant 10kw using a 12v powerdrill motor with RPM and torque spare if passed through and controlled with your regulator

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Anonymous Coward

Re: "i said it all a million times,."

"you can generate a constant 10kw using a 12v powerdrill motor with RPM and torque spare if passed through and controlled with your regulator"*

Are you:

a) Eight years old.

b) On drugs.

c) From a differnet universe that doesn't have a "conservation of energy" law.

Please study some basic physics and then come back and apologise.

* If your 12V motor is running at 834 Amps and your generator is 99.99% efficient then you *can* generate 10KW but you use 10.0008 KW to do it; a net loss of 0.0008 KW. Ye canna' change the laws of physics!

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Re: "i said it all a million times,."

there are no laws of physics, different dynamos generate different ac/dc and volts, if your a professional electrician or make nuclear reactors or have a general understanding of modern dynamos and know why they cost £5000 instead of £8 for bike lights and radios, you can probaly make a crude generator in a hour

when you put some extra money in and make motor specific to the dynamo, they can power ships and planes and national grids and spaceships

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Re: "i said it all a million times,."

"there are no laws of physics"

I love this!!

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Re: "i said it all a million times,."

if you want absolute minimum loss of power looping back to the motor, there is different types of grease and gases to put in a vacuum container cylinder, the math is all the same and none of that matters much if you can generate 10kw with a 12v power drill motor

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Re: "i said it all a million times,."

"If you think you can do it, build a smaller model. Even a model that produces no excess power but spins itself forever would be worth approximately all of the money in the world. You would become an overnight billionaire, worth substantially more than the oil companies who'd really not like you (but to whom you would pose little immediate threat). Maplin or RS (or even eBay!) would be able to provide you with an appropriate motor, dynamo and other components to give it a go."

Here's a helpful hint. People have already tried this technique. Lookup "Bedini motor" or "overunity engine". I guarantee you will find nothing independently verifiable except failures (because a verifiable success would draw instant international attention).

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Re: "i said it all a million times,."

How about I puncture your thoughts on electric motors right now?

Electric motors DO produce torque. In fact, ALL rotating shafts have this feature. Torque is a FORCE and fundamental to physics.

Motors CAN be overloaded. Ask yourself why a cable elevator (which is run by an electric motor) has a weight limit? Because if it's too heavy, the elevator motor can't pull the load.

How about something a little more prosaic? Try removing an old rusted stuck screw with your electric screwdriver or drill with a driver bit (the drill is also an electric motor). Guaranteed it won't go easy (if at all--sometimes you overtorque and snap the head off).

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Re: "i said it all a million times,."

Thing is, that number gets CLOSE to zero, BUT--and this is the important part--it NEVER REACHES zero. Without that, you can't approach perfect efficiency, and without that, you're going to lose energy, full stop (as efficiency measures that loss--or rather, the preservation of that energy).

Here's another interesting thought: an overunity engine would also by default have NEGATIVE entropy: a physical impossibility.

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Re: "i said it all a million times,."

it kind of obvious they have torque, its the push force, they do not have shaft power

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Re: "i said it all a million times,."

people can try gt all they like 100 years ago, it means nothing to a todays wind turbine direct drive dynamo

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Re: "i said it all a million times,."

a small amount of generated power looping back to power the motor and not needing any other fuel besides a start charge from the battery and already able to generate 6 megawatts in 20 turns with a dynamo out of a windfarm turbine is alot more effient then a nuclear reactor with heatpipes and waste that only generates 1kw

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"Can't get enough of that wonderful DUFF."

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It's a joint NASA/SPB project.

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Pint

Doh!

(body)

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Ah...

I was hoping for a nuclear rocket engine. But a nuclear electric engine is also good. Just less pretty (controlled) explosions. Plugging a nuclear power source into a Vasmir would be a good start to see what kind of interstellar travel we can rig up.

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Ps

I meant to click the nuclear explosion icon, for obvious reasons. I guess it's good I'll not be in charge of pressing the buttons on that thing...

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what have NASA got against space?

for a supposed space agency, they sure do seem to hate sending people into space.

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I think that they are only happy sending people into space

If they can get them back home safely.

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Re: I think that they are only happy sending people into space

bit boring isn't it? where's the pioneer spirit? bloody health & safety....

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FAIL

Re: what have NASA got against space?

I'm guessing that maybe doing science is getting in the way.. and well you now humans not being designed to live in space and therefore have to take their environment with them all the time.

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Joke

Just waiting for the next flood of paranoid hippies decrying putting nuclear fuel in space. Apparently, they reckon that thermonuclear reactions going off in space shouldn't be allowed and they don't want to pollute outer space with gamma ray producing material...

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And if anything goes wrong it only affects Canadians anyway http://en.wikipedia.org/wiki/Kosmos_954

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Mushroom

Sure why not..

..some nice warm glowing showers to melt all that ice, keep those ravenous polar bears at bay (unless they turn into super mutant bears) I won't bitch too much.

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