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Comment Re:dust (Score 1) 78

I repaired a PC that was primarily used in an automotive repair facility. That's not dust. It's soot from the exhaust. Unsurprisingly, the CD-ROM drive in the machine that I was repairing was nonfunctional because the lens was dirty.

You're right, though. I have no idea how that floppy drive is still operational after 30+ years.

Comment Re:Cool, but how does that help anything? (Score 1) 469

Hydrogen does not have to be shipped as a liquid or gas (more to the point, it wouldn't persist as a liquid without a significant cooling system). By mass, water is 13% hydrogen, hydrazine is 14% hydrogen, polyethylene is 17% hydrogen, lithium borohydride is 18% hydrogen, ammonia is 22% hydrogen, and methane is 34% hydrogen. Most of those compounds (and others) are useful to have on a ship regardless. And any sort of effective radiation shielding is going to have to be hydrogen rich no matter what; there's nothing that moderates down neutrons to easy-to-capture energies anywhere near as well as hydrogen.

Comment Re:(HAHAHA) (Score 1) 469

The fun part of it is that the hydrogen enters and leaves the rocket in exactly the same form; it's simply there to function as a working gas for the lithium fluoride.

I'm actually somewhat of a fan of metalized propellants, although that one is certainly extreme. ;) While there's no getting around fluorine's toxicity so I can't really get onboard with that particular propulsion system, I can picture lithium being managed - yes, lithium is dangerous, but so are chemicals like LOX (really, pretty much all oxidizers are extreme fire hazards, if not outright explosion hazards). Aluminum doesn't provide as much of an isp boost as lithium, but it provides a small one, plus a major density boost (and is cheap, too), and is nice and stable. I'm actually working on some experiments for a somewhat hybrid-esque design which involves aluminum structural elements designed to burn away and contribute to the exhaust stream.

Comment Re:don't get your hope up (Score 4, Insightful) 190

It doesn't matter how many hours you put in if you were enticed by and promised things that don't exist in the game. You could love the game, give it honestly rave reviews, and play it every day for 8 hours. Doesn't matter. Your playing or not playing the game, or a better way to put it is, the behavior of the purchaser subsequent to purchase has no bearing on the advertising tactics and their honesty/dishonesty in describing the game. Money should be refunded based on the request of the purchaser because of the actions of the selling company previous to purchase. Everything that happens after purchase is immaterial.

Why? Because even if someone played the game for 400000 hours, they would never get what was promised in the advertising. IMHO the penalties should go up with play time. It means that person has been defrauded of the missing material more than someone who barely plays the game.

Comment Re:Inscrutable behaviour (Score 2) 401

He's not "asking" anyone to do anything. It's a simple reality that if there was a mission to Mars coming up shortly and you passed a signup sheet around, and at the top of it was written in large letters "YOU WILL ALMOST CERTAINLY DIE AT SOME POINT DURING THIS TRIP", you'd still get thousands of signatures from people who are utterly thrilled at getting the chance and couldn't give a rat's arse about the risk.

Comment Re: meh (Score 1) 401

I knew there was a reason back in school that my binders all had pictures of sci-fi landscapes on them... it all comes full circle. Mars needs a breading program for colonists to survive... breading requires a binder... binders have pictures of Mars to encourage people to go and support the breading program!

Comment Re:1Million People (Score 2) 469

Is that not exactly what the Mars rovers were supposed to be investigating?

No, the rovers have not been gem prospecting. But the data that they've recovered would be useful for doing so. There's a lot of heavy hydrothermal veining near curiosity for example (primarily gypsum, but it's a good start!). What I wouldn't give to be there with a rover with good range...

Comment Re:Cool, but how does that help anything? (Score 1) 469

I've read some papers on the subject, and it really depends on what sort of mineral you're talking about. Mars lacks or is deficient in, as you note, a lot of the processes on Earth that concentrate ores, making certain types of ores deficient. However, there are some types of ore deposits that it's expected to be rich in. A good example is bolide deposits, like the Sudbury deposit on Earth. There a large impactor created a basin which is rich in nickel, copper, and precious metals. It's not that the precious metals came from the impactor - it's that by liquefying a large chunk of the crust, it allows it to separate out into layers. Mars is struck more often by large bolides and the resulting basins are more slowly eroded, so such deposits are predicted to be notably richer on mars.

A problem with mining on Mars however is... well, mining. Overburden problems are likely to be even worse on Mars than on Earth, and I'm sure you've seen what lengths people go through to get rid of overburden. Doing that with equipment light enough to ship to Mars and keep operating? Anything but an easy task. Now, surely there's some deposits in some places that, with good prospecting effort, are low overburden and easy to mine. But then you hit the other problem which is... not everything is found in the same place, and many things distinctly aren't. And furthermore, once you build in a particular place, you're pretty much locked in there. So how do you get everything from point A to point B? Aircraft can work on Mars, but their payload capacities are terrible compared to their size, and you have to make them very fragile. Over a few hundred kilometers, your best bet is probably "mountain roads", aka you plow aside the rocks and dirt as best you can, and accept that you're going to get low throughput/high maintenance hauling over such bad roads. Over longer distances? Honestly, your best bet (in the foreseeable future) is rockets, as expensive as they are. In the long term you can talk durable cross-planet roads, high speed rail, railguns, etc. But those sorts of things aren't practical in the near term - they represent too much embodied mass, power, and/or and labour.

It's not an easy challenge

Site selection is going to be critical. The goal in the near future shouldn't be 100% independence, because that's not realistic. It should be, "what's the highest percentage of this import mass that we can eliminate?" Pick those low-hanging, high-demand fruits first.

Comment Re:Everything under the sun at Amazon (Score 1) 139

It's even more painful for me. I live in the same state that Digikey is located, so I have a real problem paying that much for shipping when it's not going very far. However, I live far enough from their location so that it's not worth it to drive there. (I don't know if they even offer will-call)

Comment Re:Well duh (Score 1) 139

Even *WITH* Prime, 2-Day shipping is not always 2 days. In fact, I just placed an order yesterday which was eligible for prime. I got a "Shipped" confirmation email this morning, but the expected delivery date is 4 days from now.

Also, sometimes the items are shipped more than 2 days AFTER the order is placed. What good is free 2-Day shipping when it takes them a week *BEFORE* they ship it?

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