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Comment Re: But (Score 1) 118

We'd do far better to direct such efforts to more realistic access methods, such as a Lofstrom loop or variant thereof, which requires no unobtanium and is far more efficient (space elevators lose huge amounts of energy to transmission losses, throwing away a large chunk of the advantage that they gain from bypassing the rocket equation). Active suspension via recirculating kinetic transfer, by one means or another, is something we can do today.

Great post and I'm all for any crazy contraption (by today's perspective) that can reduce the cost of space travel by factors of 100. It seems like you have a great handle on the realities and problems of space elevators. But I think you should apply some of that skepticism to the Lofstrom loop as well. Its quite a stretch to say maintaining 7850 cubic meters of iron moving at 14 km/s is something we can do today.

This falls under a certain /. post category. In summary: An infant technology that gets a ton of hype despite seemingly insurmountable challenges is crap whereas a totally un-hyped infant technology will solve all our problems if we'd all just take a look (see: thorium reactor, any number of alternate fusion containers, etc).

Comment Re:In other words... (Score 1) 387

Le Mans? Weak. Turbo pumps on rocket boosters probably operate in the highest stress environment of any engine ever designed! Extremely cold fuel pumped to extremely hot engines at 10+ G's at microsecond precision baby!

The point is, just because the WEC and Le Mans (my favorite race fwiw) is harder doesn't mean NASCAR engines don't also deal with a ton of stress requiring advanced development. Also, there is nothing in the sporting regulations ( about not fixing engines. I've seen plenty of radiator replacements, maybe a turbo or two, and a full rear end swap (transaxle & 4 minutes!!!). All it has are time penalties for using more than one engine for qualifying and race.

Comment Re:Manufacturing is Hard (Score 1) 211

it's way cheaper than that, if you ignore the value of my time spent designing it and doing software tooling to support the fixture.

I doubt your boss ignores that time and I really hope you don't ignore the value of your time. And don't forget lost opportunity cost where you could have been refining or iterating your specific product.

Comment Re:In other words... (Score 2) 387

Other fun facts...

-All the cars might look the same but the top and bottom teams differentiate themselves via coatings. All sorts of surface physics come into play and the fastest cars have the most advanced textures.

-They use pushrod V-8's but piston speeds are equivalent to those in F1 cars...back when they revved to 16k RPM. An engine needs very advanced designs and lubricants to sustain that for 3-4 hours.

That said, I'd say its probably one of not the most engineering oriented. And I'm not really a fan of the ovular race format.

Comment Re:Manufacturing is Hard (Score 1) 211

^Second this.

I'm in the middle of spinning up my second contract manufacturer for a relatively simple device. It took 4 weeks just to load the Bill of Materials in their system! That was after all the kinks were worked out on our end and with direct relationships with half the suppliers. Now they can finally order the parts which have generally have a 6-12 week lead time. Digikey might have 800 motors in stock for 200 drones but you need to talk to at least 2 different middlemen if you want 1,000,000 of something. Don't forget $50k for test fixtures. Then there is the NPI build (100 units), validation (2-4 weeks), run 1 (1000 units), line shut down for re-validation and a slow ramp up.

Its going to take us about 8 months for us to go from contract signing to quantities of 15k/month...for a finished design. Delivering 200k by a specific date means you need to build production capacity of greater than a million units a year. And that's a whole other step up from what I'm dealing with.

So yeah, $3.5M is quite a bit to disappear but I doubt the founders are walking away with it. More than likely a lot of mistakes were made, bad contracts signed, checks were written for the wrong things and a few opportunistic middle men took the rest. Our finished good price went up almost 15% between final full BOM guaranteed CM quote and production. The best thing to do for situations like this is cut off funding real soon and use some of your extra money to hire a engineering manufacturing services consultant....or just take the money and run.

Comment Re:Climate has never not been changing. (Score 1) 369

I personally haven't touched a satellite (who's orbit is reasonably approximated by Newton), a transistor on a die or felt a photon quatumly interact with the electrons in my hand but I have thrown a baseball, driven in a car, sat at my desk, and basically moved around the earth in a way that Newton can closely describe.

I'm guessing you're in high school (or closely removed from) based on your attitude and mention of the SAT and your 100% or nothing view of the world. Someday you'll see it helps to look at things with a little nuance. Till then carry on splitting hairs for inconsequential victories while letting everyone know you're angry in your well fed and sheltered existence.

Comment Re:Climate has never not been changing. (Score 3, Insightful) 369

The problem that I have with anthropogenic global warming is that it started out sounded like a science-based issue, but it has since moved into the realm that's more reminiscent of a religion (complete with established dogma, punishment of heretics, an apocalyptic theology, etc.).

So what? The science is still there no matter how much perceived crap is on top of it! The greenhouse effect still traps radiated heat from sources such as incident light (see: your car with the windows up in the sun). CO2 acts as a greenhouse gas in atmosphere (see: Venus). The carbon cycle has recorded itself in all sorts of ways so we have a general picture of whats "normal" (see: tree rings, ice cores, fossil record). Humans are currently contributing carbon to the atmosphere that is NOT part of the usual cycle (see: oil rigs digging 5 miles into the earth) but was sequestered a long time ago when conditions were drastically different.

If you stop worrying about how some guy says some data point may be off by 0.3% and look at what we know about the physical world we occupy it should be obvious that we should be spending time and money on reducing our carbon footprint.

Comment Re:NASA ignoring satellite measurements... (Score 4, Funny) 369

Lottery Commission: "Congratulations! You just won our largest ever estimated jackpot! $539M is greater than the next biggest jackpot by 0.08% +/- $2k! We'll know for sure in 2 weeks."
You: "Yawn. I only deal in absolutes and percentages greater than (some moving target)% and spend all my time pointing out anything less than perfect information delivered by time travelers from the future. As you can imagine the internet keeps me too busy to deal with that worthless jackpot."

Comment Re:I don't see it. (Score 1) 91

Your tone indicates any debate with you is a lost cause but to anyone else, environmental friendliness and modern lifestyles don't have to be mutually exclusive. OP's computer is already built but going forward its easy enough to start being smarter about the environment. In many places its already cheaper to use solar than coal. And batteries are almost cheap and big enough to alleviate all the "but what if it's cloudy" fears for most places outside the Arctic circle.

As for me first... I have a 7.8kW solar array, chose the car that gets 30% better mpg and I'm about to start buying carbon offsets which at a national level would cost FAR less than another war in the middle east. Not perfect but it is indeed a start.

And with that, I'll leave you to your pessimistic whining.

Comment Re:I don't see it. (Score 4, Informative) 91

I hate to ask such a dumb question, but why do we refer to them as "fossil fuels"?

Actually, that's quite a reasonable question to ask and as your post appears genuine enough here you are...

Oil (petroleum) and coal are both the result of geological processes (heat/pressure) acting on the fossilized remains of ancient organic (carbon based) life. Plankton and algae in oil's case and trees for coal. Natural gas is usually found with or near the other two and formed with similar processes. A fossil is basically any trace of life preserved in rock which does include dinosaur bones...but also anything else that used to live on this planet. And alliteration is always catchy.

Nothing is finished until the paperwork is done.