Environment & Energy

longship

(40,416 posts)

23. I never said that one would get to light speeds.

Thu Nov 7, 2013, 10:43 AM

Nov 2013

But, no matter. The applicable Newton law is all about momentum. True. Light has no rest mass, but light speed is as large a velocity one can have.

Again, it's all about the rocket equation and how to most efficiently move a rocket through space. That's why ion drives work so well in spite of their low thrust. The ions are booking when they exit the nozzle. I thought that LASERs might provide a similar mechanism.

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Thorium vehicle will run 100 years on 8 grams of fuel [View all] OnlinePoker Nov 2013 OP

Won't take long for CFLDem Nov 2013 #1

Sorry, but bunk johnd83 Nov 2013 #2

100% WRONG!! PamW Nov 2013 #5

I think you misunderstand my point johnd83 Nov 2013 #7

100% WRONG PamW Nov 2013 #16

The thorium reactors use a particle accelerator johnd83 Nov 2013 #17

WRONG AGAIN!! PamW Nov 2013 #20

There is plenty of water to moderate neutrons in a damaged reactor johnd83 Nov 2013 #25

Reactor Physics 101 PamW Nov 2013 #29

The other advantage of thorium is the decay products become inert much faster johnd83 Nov 2013 #30

Actually it is NOT a huge assumption... PamW Nov 2013 #35

I still don't understand your point johnd83 Nov 2013 #36

Criticality in non-operating - but NOT in melted. PamW Nov 2013 #39

You are 100% WRONG johnd83 Nov 2013 #38

100% WRONG!!! PamW Nov 2013 #40

Yes, I was going to remark about the five ton engine it would take Warpy Nov 2013 #27

I want a nuclear vacuum cleaner! longship Nov 2013 #3

Those are different technologies johnd83 Nov 2013 #4

Yup! They are talking about a Sterling engine now. longship Nov 2013 #6

The Voyager spacecraft only hase a few hundred watts of power johnd83 Nov 2013 #8

Voyager has shut down its cameras. Long ago. longship Nov 2013 #9

I think for the next 100 years or so it is going to be mostly manned/unmanned craft johnd83 Nov 2013 #10

Fusion, unfortunately, is probably a long way off. longship Nov 2013 #11

Fusion power is not really that far off johnd83 Nov 2013 #12

But the technology is not yet practical. longship Nov 2013 #13

The technology I linked to is a magnetic containment plasma system johnd83 Nov 2013 #14

Yes! And I've heard of another in Europe. longship Nov 2013 #15

Correct. PamW Nov 2013 #22

Fusion propulsion is a lot easier than electricity generation bananas Nov 2013 #18

If you're going to use it for propulsion, yes. longship Nov 2013 #19

Not quite... PamW Nov 2013 #21

I never said that one would get to light speeds. longship Nov 2013 #23

Look at momentum per unit energy PamW Nov 2013 #41

Thanks. longship Nov 2013 #42

That's if your concern is momentum per unit energy; but often it's not, in rockets muriel_volestrangler Nov 2013 #43

Let's examine TOTAL mass.. PamW Nov 2013 #44

Well, yes, that's the point - you use nuclear power, or solar (ie external) muriel_volestrangler Nov 2013 #45

IF Polywell Fusion works VASIMIR is DOA FogerRox Nov 2013 #46

Does anyone have the faintest idea what process is being claimed here? muriel_volestrangler Nov 2013 #24

I didn't get that either johnd83 Nov 2013 #26

"And he hasn’t released any papers, only press releases." arcane1 Nov 2013 #28

I'll try to post on it later - basically, you can increase decay rate by jiggling it with a laser bananas Nov 2013 #33

Finally found a somewhat relevant hit bananas Nov 2013 #34

Thanks - that gives us a theory that the laser is relevant muriel_volestrangler Nov 2013 #37

Oh, I agree, it's as credible as his "USEING HELYXZION TECHNOLOGY WE CAN CURE “ALL” DISEASE" bananas Nov 2013 #48

I forgot that one. kristopher Nov 2013 #49

Not the faintest. FogerRox Nov 2013 #47

It won't work, period. NNadir Nov 2013 #31

Why, Are we still thinking in individual cars, individual propulsion systems, ... CRH Nov 2013 #32