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Comment Re:REALLY? (Score 1) 42

I should point out that this is the prototype for a tracks-and-arms machine intended for ongoing Fukushima clean-up. We can't really ask what they did in Chernobyl - they just sent in unprotected conscripts to clean up - even replace the soviet flag when the radiation bleached it - after which they were either euthanized or tranquilized while the radiation poisoning ran its course. (Though, in the circumstances, it's hard to tell the difference, there) The lucky survived a while without cancer.

These days, though, we have tungsten, boron nitride, and leaded glass. And now we have something else to carry it for us. Which is good, because if this lights a candle under Cyberdyne's butt, they're likely to actually ship product - someone's likely to ship product - before we next need something like this.

Comment Re: Avatar? Seriously? (Score 4, Informative) 42

As the designer notes in an earlier interview, earlier models had wider hips and a different torso shape, with a more bio-inspired, "automotive" design. Range of motion questions, as well as seasickness caused by the robot's swaying gait, caused them to remodel the joints until the machine's proportions bear an uncanny resemblance to Cameron's AMP suits. The designer of the real one praises Cameron and his team's vision and engineering acumen. While it wasn't designed by looking at Avatar's mecha, it represents a case where there was some convergent evolution during the design process.

Comment Re:Not everyone is the same (Score 2) 297

Protip:

Nonplussed has two meanings. I tripped on this last week.

nonplussed |nänplst| (also nonplused)
adjective
1 (of a person) surprised and confused so much that they are unsure how to react: he would be completely nonplussed and embarrassed at the idea.
2 North American informal (of a person) not disconcerted; unperturbed.

Comment Re: Honestly, pretty neat (Score 2) 141

Did you RTFA?

The hacker news discussions on this post took off. I just want to emphasize that this post is not a complaint. I’m not whining over this. I’m just showing some interesting side-effects of my email in the license text. I actually find these emails interesting, sometimes charming and they help me connect to the reality many people experience out there.

Comment Re:Imagine (Score 1) 477

Actually, Bussard's polywell fusion would work great in space, considering that the enormous vacuum chamber a test reactor would require would be unnecessary, and so long as your radiators can dissipate all the waste heat, you could build some kind of space-cruiser ship without much in the way of launches by launching the magnetic coils in an IKEA-style "flat-pack" configuration, and unpacking them on orbit.

It's still "hot" fusion, but the only technical hurdle to this is scaling it up to critical volume is expensive, if you need to do it where there's air. Small scale test reactors work, and work reliably, and are even used as neutron sources sometimes - but power is proportional to the square of volume or something, and there's a critical volume where any smaller reactor cannot possibly reach break-even.

If the Rossi E-Cat works* - whether it generates energy is important, not the physical process through which it does - you could build a very compact, fast spacecraft with Roger Shawyer's superconducting, second-generation thruster which is supposed to generate (according to IBTimes) "produce thrust many orders of magnitude greater than that observed by Eagleworks" with an implication that it operates at the same power level. In that case, we now have a rather compelling power-to-thrust ratio, and our choice of electric power sources with Russian sodium-cooled satellite fission-reactors as a backstop if none of the lower-mass fusion reactors are ready in time.

*(I'm not going to rule it out - but I'm not going to hold my breath, either.)

Comment Re:My impressions after skimming through the paper (Score 1) 477

"Making sense" is a generic statement which is expected to be understood within the given context.

Except it was not understood within given context. What made sense is, the results did not fit the null hypothesis, and probably didn't fit H1, either. (Null: No thrust detected beyond a threshold of 80 watts of photon pressure. H1: Anomalous thrust generated proportional to input power, exceeding photon pressure.) This is just the scientists saying, "We can't yet rule this out as a crank. Please send more money."

Comment Re:This is BIG news - If you want to know more.. (Score 1) 477

I fear you've misstated the Oberth effect by conflating it with rockets' efficiency at speed. The Oberth effect says you can get more thrust out of a unit of fuel by leaving it with less residual potential energy, by depositing it deeper within a body's gravity well. This coincidentally happens to be at the fastest point of a gravity assist.

Also, you leave out an interesting tangent, which is that rockets' maximum achievable speed is related to exhaust velocity. At this point, the rocket is accelerating the fuel away such that the fuel is at a standstill relative to an observer. To go faster with the same exhaust velocity, the fuel would end up chasing the rocket, which is a physical impossibility according to currently accepted laws of physics.

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