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Comment Not theory (Score 1) 137

Unless you have actually tried to build a rotating space station, your answer is also theoretical.

They have tried to extend tethers in space, and run into multiple problems caused by them being not-rigid. Gemini 11 (which was tethered to it's Agena to test just these things) encountered problems with spin-up due to this and other dynamics issues. The problems I cite spring directly from experience, mathematics, and engineering.

So no, my answer isn't theoretical.

Comment Re:Artificial Gravity (Score 4, Insightful) 137

From what I've read, it can be done cheaply with a long tether and a counter weight at the other end.

It can be done cheaply in theory... In practice, there's all sort of complications with tether deployment, spin up, and stability. Plus you can't dock with a station spinning like that, so now you encounter the practical problems with spinning down. (All these problems are caused by the fact that tethers aren't rigid.) Any time you need to maneuver the station (for re boost or to avoid debris), you also encounter the spin-up/spin-down problems. Then there are the problems the spin causes in keeping your solar panels aligned with the sun, and your radiators aligned away from the sun. Any directional antennas also suffer from the same problems. Etc... etc...

Easy in theory, difficult in practice.

Comment Re:How much to re-create Apollo? (Score 1) 287

If you can get - for the same launch cost - not 70 tons, but 1400 tons to orbit, even if they are in 54 ton, not 70 ton lumps - it starts being really questionable what the benefit of the 'shuttle derived' heritage is buying you.

It stops being questionable when you stop comparing prices - and start comparing what you get for those prices. Splitting the payload increases the amount of parasitic mass, I.E. non payload mass such as the support systems the payload requires until joined up in the final assembly. Splitting the payload also considerably increases the total risk of the mission - both by increasing the number of launches required and by adding rendezvous, docking, and assembly steps not required by a unitary payload.
 
Seriously, while I can't and won't argue the SLS is a good idea - there's a lot more to the equation than simply price. My minivan is much cheaper than a full sized pickup truck, but nobody sober and in full possession of his senses would ever confuse one for the other. No sane person would ever send one to do the other's job.

Comment Re:How much to re-create Apollo? (Score 1) 287

How expensive would it be to re-create the Apollo program?

Outrageously expensive - because pretty much every piece would have to be re- or reverse- engineered, production facilities established and qualified, all of the production and part QA processes and procedures re-established and re-validated, etc... etc...
 

In other words, would we save $BIGBUCKS by building on what we have instead of starting nearly from scratch?

The problem is... there's nothing to build on. Apollo is over forty years in the past, and there's nothing left of it. Zip, zilch, NADA. Pretty much very manufacturing process has changed (they welded together parts we'd machine in one piece out of a single block nowadays for example). A good chunk of it's electronics were analog - and used very low part count IC's (for both digital and analog) that were manufactured using processes that haven't been used in decades. Etc... etc...

Beside which - what makes you think an Apollo-Saturn launch was cheap? In current year dollars, they cost over a billion a pop out of pocket. (I.E. not considering sunk costs or amortization.)

Comment Re:Only a penny a page, duplex? (Score 1) 3

I based the estimate on $5o for a cartridge that prints an average of 3,000 pages. A color laser would be nice, but as you say, far more expensive both in up-front costs and toner. And changing toner in a color printer is a PITA, at least the ones at work were.

Comment Re:Why were the accounts around to begin with? (Score 2) 100

Yeah... I call bullshit.

I had an old Yahoo account that has definitely been inactive for over 5 years. I just tried to log in, and it tried to send a validation code (good?) to a Hotmail address that I haven't used in even longer than that. That Hotmail account appears to have been properly deleted and re-registered (by someone whose security questions are in a different language than I would have used).

Comment Re: Send it an email? (Score 2) 100

So... They're just like post office boxes, on which the system was modeled, or street addresses. In both of those cases, someone else can get your address after you leave and communicate in your name!

While getting your own domain is significantly easier than getting your own post office or private street, the effect is still the same. Those are the only ways to reliably use their respective addresses as identities.

Comment Re:Professional attention whore strikes again (Score 1) 913

"Death to All Jews" one in particular is not remotely anti-semitic.

I don't know what planet you're from or what your native language is - but here on Earth, in English, "Death to All Jews" is about as anti-semitic as it gets.
 

But I do rather fear the consequences of proving Trump right, of validating the echo chambers of tens of millions of people who were right-leaning fence sitters until they saw the proof stack up that the mainstream media really is full of hysterical, baldfaced lies.

First, present me with evidence that they lied. (And I think that's the real problem here - you don't even begin to grasp what PewDiePie did and why it's objectionable.)

Comment Re:Never Fails (Score 2) 131

Someone comes up with an idea that's pretty good, is designed for people to work part time to pick up some cash, minimal regulations, etc. and it's a pretty good thing for everyone all around.

I think you're posting in the wrong discussion - because there's considerable regulation both when it comes to hiring labor and when comes to transporting paying passengers. Regulation that Uber has consistently tried to circumvent, first with their nonsensical "ride sharing" claims, then with their equally nonsensical "we're just a tech company" claims. The only people it's "pretty good" for are Uber's investors, because they collect all the profit and shove all the risk onto the drivers.

Comment Re:Irreverent vs. Inappropriate (Score 1) 363

So much this. To take the actions he did, PewDiePie had to be either supremely ignorant of the world around him, or supremely egotistical (I'm so big they won't dare take any action against me), or both. (Or, well, an actual anti-Semite but that's also covered by the earlier cases.)

A poster elsethread is trying to make the case that he actually didn't mean it... But misses that "not meaning it" doesn't absolve of him of responsibility for actually doing it. YouTube and Disney rightfully don't care whether he meant it or not - because he actually did it.

Comment Re:Dogfish Head - Chateau Jiahu (Score 1) 109

In keeping with historic evidence, Dogfish brewers use brown rice syrup, orange blossom honey, muscat grape, barley malt and hawthorn berry. The wort is fermented for about a month with sake yeast until the beer is ready for packaging.

So you have evidence of the fermenting time? And the yeast strain? No, you don't. So, no, you don't have a historical beer. (And that's setting aside the fact that 'brown rice syrup' isn't brown rice. Etc... etc..)

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