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Comment: Re:May I suggest (Score 2) 276

by AJWM (#48181757) Attached to: No More Lee-Enfield: Canada's Rangers To Get a Tech Upgrade

And everyone who has played Counter-Strike knows that the AWP (http://counterstrike.wikia.com/wiki/AWP) is a great Arctic weapon.

No, they know that the game designers thought it was a great Arctic weapon.

Any relationship between what game designers think (or at least, put in their games -- ditto for authors) and the real world is entirely coincidental.

Comment: Re:Why Cold Fusion (or something like it) Is Real (Score 1) 340

by AJWM (#48174571) Attached to: The Physics of Why Cold Fusion Isn't Real

You keep asserting failure to reproduce the results. I can understand that, you're from Caltech.

However, that turns out not to be the case.

I would recommend to you and to everyone here Charles Beuadette's thoroughly researched and easy to read study of the field, including the mistakes, including the shameful errors of scientific protocol, on both sides. (Basically, the hot-fusionistas ignored the excess heat claims and put their hands over their ears chanting "la la la where are the neutrons?"; P&F erred by claiming a mechanism instead of just presenting their excess heat measurements and saying "this is weird, we're highly experienced electrochemists but can't come up with a chemical explanation for this. Any ideas?")

Anyway, the book is Excess Heat: Why Cold Fusion Research Prevailed by Charles G. Beaudette. It's not up on the latest work (copyright 2002 unless there's a later edition) but it's a very worthwhile read -- a lot of the questions raised by various slashdotters are answered here -- and documents well the first few months and years of both the controversy and various lab results.

Comment: Re:Still open (Score 1) 340

by AJWM (#48174473) Attached to: The Physics of Why Cold Fusion Isn't Real

How many attempts did it take to first clone a mammal? How many more attempts did it take before some other lab repeated the process?

Clearly they didn't do good science.

Repeating 19th century experiments with 21st century equipment is pretty easy. Doing 21st century experiments (or, okay, very late 20th century) is hard.

And even at that, back in high school physics when we were replicating Millikan's oil drop experiment (only with latex microspheres rather than oil drops) some people came up with a charge only 1/3 that of what's accepted for the electron. Were all those people who claim you can't have an isolated quark wrong, or is it just a trickier experiment than it sounds from a written description?

Siegel makes the arrogant mistake that all he needs is "the proper equipment" to replicate an experiment. If it's not in a field he has a few thouand hours of experience in -- say, electrochemistry or calorimetry for a high-energy physicist -- he needs more than the proper equipment, he needs somebody skilled in the particular field in question. Put another way, how long would it take a physicist to clone a mammal?

Comment: Re:"repeatable independently verifiable reproducti (Score 1) 340

by AJWM (#48174425) Attached to: The Physics of Why Cold Fusion Isn't Real

Unfortunately since about 1989 or 1990, the US Patent Office has refused to consider anything dealing with cold fusion, probably because the high energy physics mafia convinced them it was akin to perpetual motion.

Rather surprising, considering some of the things the USPTO has issued patents for.

Comment: Re:Heavier than air flight is impossible (Score 1) 340

by AJWM (#48174419) Attached to: The Physics of Why Cold Fusion Isn't Real

Nuclear physics doesn't work this way.

High energy nuclear physics, no. All that extra energy to overcome the Coulomb barrier has to go somewhere, and moving nuclei at that speed gives them precious little interaction time.

Why is it so inconceivable that some other reaction mechanism, which keeps the nuclei in close proximity at lower energies for longer times, has different preferences for reaction pathways?

Muon-catalyzed fusion, for example, if fusion in condensed matter is so heretical. (Of course, muon-catalyzed fusion turns out to be an interesting curiousity rather than a useful power source unless and until we come up with a way of easily making muons. Fusion in condensed matter may turn out the same -- a great way to produce low grade excess heat, but not much else.)

Why assume neutrons or gammas if you don't understand what's going on? Because hot fusion tells you so? They're not talking about hot fusion, so your assumptions are bad science. Superconductivity is bad science too if you go by what happens at room temperature.

Comment: Re:Replace rockets with something reasonable. (Score 2) 348

by AJWM (#48166087) Attached to: White House Wants Ideas For "Bootstrapping a Solar System Civilization"

We already had a SSTO it was called the Saturn V.

Uh, no. You're confusing HLLV (heavy lift launch vehicle) with SSTO (single stage to orbit). Saturn V dropped two stages on the way to orbit.

The original Atlas was the closest we've come to an actual flying SSTO, it only dropped the two outboard engines, the tankage and sustainer engine made it the rest of the way.

Now, as a thought experiment you could take the Saturn V second stage and replace its five J2 engines with a Shuttle SSME (and move a bulkhead to allow for the different LH2/LOX burn ratio) and it would make orbit as a single stage. Ditto with the Shuttle External Tank and six SSMEs. But none of those would have reentry and landing capability, and if it's not reusable there's not much point to SSTO.

As for not seeing the point, it must be sad to live in a mind with such limited imagination. My condolences.

Comment: Keeping it reasonable. (Score 1) 221

by AJWM (#47959989) Attached to: Secret Service Critics Pounce After White House Breach

Isolated event, and the guy was brought down. There'll always be a risk as long as their are fanatics or loonies who don't give any though to their own personal safety, but there comes a point of diminishing returns.

Suppose they hired 10 times as many Secret Service agents? That just increases the odds of one of them going bad and offing the President himself. (Not a likely event, but having 10x as many agents also means more chances of confusion in a crisis, etc, etc.)

Security is never perfect (wasn't there an incident some years back where an intruder wandered into the Queen's living quarters at Buckingham Palace?) That's one reason we have a line of succession -- it's not like the government collapses in the case of an untimely death.

Mind, given the choices of VP over the past few presidencies, that line of succession might actually be helping lower the odds of someone trying to assassinate the Prez.

Comment: Re:Blastoff From the Past (Score 2) 19

by AJWM (#47934037) Attached to: ULA and Jeff Bezos' Blue Origin Announce Rocket Engine Partnership
The basic aerospike SSTO design goes back to the mid to late 1960s with Phil Bono's work (and a couple of his patents), and designs by the Douglas (later McDonnell-Douglas) corporation (SASSTO, ROMBUS, Pegasus, Hyperion and Ithacus). Chrysler Aerospace (IIRC) had a similar proposal for the initial Space Shuttle studies. Boeing's "Big Onion" came a bit later, after O'Neill's 1974 "Physics Today" paper kicked off the whole L5/space colony/solar powersat thing.

The designs were revived in the 1980s by Gary Hudson and Pacific-American Launch Systems (Phoenix) and later by General Dynamics (Millennium Express --disclaimer, I helped name it) as their proposal for the DC-X competition.

Yes, New Shepherd was clearly influenced by all that (as have several others, including a Japanese suborbital test vehicle). The design makes sense for a number of reasons:

  • structure weight is critical for SSTO, and the closer you get to a sphere, the better your structure-weight to propellant-volume gets, hence the relatively squat shape
  • the rounded-cone shape makes a great reentry vehicle, with some maneuverability (assuming asymmetric mass distribution)
  • the heat-shield on the base serves to protect against engine exhaust on launch as well as reentry heating
  • aerospike nozzles are inherently altitude-compensating, so potentially more efficient

Of course there are downsides to the design too, particularly in terms of integrating the design so that it's light enough for SSTO, and starting and controlling the large number of thrust chambers (usually at least 16, some designs with 24 or 32).

Comment: Re:Knee-jerk reaction (Score 1) 33

by AJWM (#47897117) Attached to: Curiosity Rover Arrives At Long-Term Destination

It still met the pre-mission criteria for life. That the other experiments gave confusing results was a contributing factor to wondering if those criteria were correct.

There's some indication that those other experiments weren't sensitive enough to detect life signs even in Earth soil samples from places like the Atacama desert in Chile.

In 2003, a team of researchers published a report in the journal Science in which they duplicated the tests used by the Viking 1 and Viking 2 Mars landers to detect life, and were unable to detect any signs in Atacama Desert soil.[21] The region may be unique on Earth in this regard and is being used by NASA to test instruments for future Mars missions. The team duplicated the Viking tests in Mars-like Earth environments and found that they missed present signs of life in soil samples from Antarctic dry valleys, the Atacama Desert of Chile and Peru, and other locales.

In 2008, the Phoenix Mars Lander detected perchlorates on the surface of Mars at the same site where water was first discovered.[23] Perchlorates are also found in the Atacama and associated nitrate deposits have contained organics, leading to speculation that signs of life on Mars are not incompatible with perchlorates.

(from http://en.wikipedia.org/wiki/A...)

And speaking of perchlorates and the Viking biology experiments:

On 2006, scientist Rafael Navarro demonstrated that the Viking biological experiments likely lacked sensitivity to detect trace amounts of organic compounds.[36] On a paper published in December 2010,[25] the scientists suggest that if organics were present, they would not have been detected because when the soil is heated to check for organics, perchlorate destroys them rapidly producing chloromethane and dichloromethane, which is what the Viking landers found.

(from http://en.wikipedia.org/wiki/V...)

Comment: Re:Knee-jerk reaction (Score 5, Interesting) 33

by AJWM (#47895565) Attached to: Curiosity Rover Arrives At Long-Term Destination

"the proposal lacked specific scientific questions to be answered, testable hypotheses, and proposed measurements and assessment of uncertainties and limitations."

Sounds like the report was written by physicists, not geologists or biologists.

I figure "we're going to look around, crack open a few rocks and do some chemical analyses to see what's there" is pretty good science.

On the other hand I also wonder why in almost 40 years nobody has yet tried repeating the labeled-release experiment on Viking which tested positive per the pre-mission criteria for signs of life.

Comment: Re:LOL (Score 1) 213

by AJWM (#47895517) Attached to: Congress Can't Make Asteroid Mining Legal (But It's Trying, Anyway)

Who in their right mind was part of this Treaty to begin with? No one in their right mind.

Bear in mind that if the treaty dates to 1967, it was being worked on in 1966, possibly earlier. At that time, the US was seriously worried that it might lose the space race to the Soviet Union (who were still racking up "firsts" faster than the US), so there was probably an aspect of bet-hedging to it. (1967 was also the "summer of love", so, hippies, and height of the Viet Nam war, so, distraction. So yeah, not in their right minds.)

When the Moon Treaty (also known as the treaty on the useful pieces of outer space) reared its ugly head some years later, plenty of people loudly and vigilantly campaigned to avoid it being ratified. (The successful effort was largely led by the L5 Society -- which was quietly thanked some years after that by several foreign (*cough USSR cough*) nationals because they didn't want it either.)

Comment: Re:Asteroid value (Score 1) 213

by AJWM (#47895477) Attached to: Congress Can't Make Asteroid Mining Legal (But It's Trying, Anyway)

An article. Wow.

Try reading up on the parent bodies of meteorites -- we know of quite a few -- then look at the composition, particularly of e.g. siderites. (Sure, plenty of stony meteorites too, still typically ~20% iron/nickel.)

Not that much carbon, actually. Lots of iron and nickel, and significant amounts of e.g. platinum group metals (same columns in the periodic table as iron and nickel). Fortunately there is some carbon, because it turns out that one of the easiest ways to separate out the different metallic elements is through selective fractional carbonyl precipitation. (React the metal mass with carbon monoxide, heat the resulting gas to the specific temperature at which the specific metal carbonyl breaks down, then collect the pure precipitated metal and recycle the CO.) You definitely want to do this in space, metal carbonyls are pretty toxic.

Comment: Re:Great news (Score 2) 269

by AJWM (#47886719) Attached to: Massive Study Searching For Genes Behind Intelligence Finds Little

Yup. They assume a direct relationship between "intelligence" and academic achievement. There ain't.

While it's unlikely that someone with an IQ of 80 will go on to great academic achievement, there's no guarantee that someone with an IQ of 130 will either. Plenty of high-IQ folks who got too bored with school and dropped out, or sidetracked by something which caught their interest so that they neglected their studies, etc. Probably most high academic achievers have high(-ish) intelligence, but the reverse is not necessarily true.

And, as you point out, the variation could be to a number of genes with small effect rather than a couple with a big effect. Wonder if they correlated for genetic tendency to AD(H)D?

Today's scientific question is: What in the world is electricity? And where does it go after it leaves the toaster? -- Dave Barry, "What is Electricity?"

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