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Comment Re:Low end drives are too expensive (Score 3, Insightful) 269

The case alone costs about $12 to buy the raw materials, cast, and precision machine. The only difference between the 250GB and 1TB version is the number of platters, quality of platters and model of read/write heads. The profit margin on the 250GB is probably about 15%, just the same as the model with the high end 1TB platters & read/write heads. Eventually you run in to a price floor, which is based on the physical reality that the drive is made from high grade machined aluminum.

Comment BoeingCalc (Score 2) 704

BoeingCalc was the first spreadsheet that had worksheets that were interconnected. The user interface was terrible (terrible) but if you're an excel wizard, you'll have a rough idea of what you're looking at. The very first version supported files up to 32mb in size. In 1982! Imagine that. I actually "inherited" a copy of BoeingCalc on old 5 1/2" floppies, but they're so old I wasn't able to retrieve the files (only the directory listing) off them, and as far as I know I'm the only amateur computer historian with a (possibly) functional copy/physical disk of the stuff.
If anyone is able to help/assist, my website and boeingcalc info is in my sig below.

Comment Ultra-dense atmosphere at fault? (Score 4, Insightful) 39

Wouldn't Titan's ultra-dense atmosphere have something to do with this? Most meteors come in at a high angle of incidence, meaning they graze the atmosphere, then fall in as they're slowed down to a capture speed.
Titan's atmosphere is something like what, three times as dense as Earth's atmosphere? It's up there with Venus, not Mars or Io, so shouldn't we be comparing it to planets, not moons? Keep in mind that visually, Titan is only about 8% smaller than Mars, and quite a bit larger than Earth's moon.

Comment Re:well, this article's lost it (Score 1) 280

RDP via VPN is very usable, and it will only get better. RDP from windows to windows machines is very, very good. It's one of the very few things Microsoft does better than anybody else. VirtualBox has excellent RDP support as well, and it's extremely fast and easy to use.
Thin clients have finally arrived... just in a way nobody ever expected.

Comment Re:WRONG (Score 1) 132

NASA will likely select a launch vehicle down the road and fund it separately. Being the ISS, it's possible that they will split the module cost with international partners, and then fund the rocket from their budget. Or one of many other options. Bigelow doesn't have their own rocket program so it wouldn't make sense to roll the launch vehicle into the same invoice.

Comment Re:At 44 with the same 30-inch belt size I had in (Score 1) 372

2. cutting out simple sugars/carbs makes it vastly easier to cut calories out of your diet. minimizing carbs (basically anything at 7-11, as it has a shelf life of about five years) and maximizing fats/protein means that your calorie density is going to be much lower, it will take longer to digest, and in general, you'll feel full longer. simple carbs is like eating high octane jet fuel for running marathons, and then sitting on the couch. you don't burn it so your body converts it to fat while you type passive aggressive emails to your boss and coworkers
at the end of the day if you want to lose weight, calories in calories out, but smart dieting makes this a lot less painful. if you decide to diet using only multivitamins and cans of coke, you're going to be starving all the time with wild mood swings due to your blood sugar spiking every couple of hours.

Comment Re:Been there done that (Score 1) 59

The DC-X program never made it above 10,000 ft and didn't have a follow-on project*, while the Ares I-X was an avionics package with a dummy load quite literally strapped to the top of a spare Space Shuttle SRB. The only reason the Shuttle survived as long as it did was inertia and the fact that nobody wanted to stand up and throw money at a new manned spaceflight program after the embarrassment that was the Shuttle. Thank god the Shuttle (while awesome) is dead and we can use much safer (and cheaper) technology now.
*unless you want to count the X-33, which as it turned out proved that SSTO is a terrible idea. SpaceX may yet beat the entire United States defense industry to a fully reusable manned spaceflight program with their grasshopper prototype that they've been actively testing.

Comment Re:Cool... (Score 1) 165

This is somewhat disingenuous. Physics is physics and rocket technology hasn't improved much since the Centaur (hydrogen rocket) engine in the mid-1960s because they're already getting close to the theoretical maximum energy from chemical rockets. This is sort of like saying we shouldn't develop spoons and forks at the turn of the last millennium because by 1935 we'll have developed the spork. Cutlery has been a mature technology for about two thousand years now, and you can't really improve on it. Short of FTL travel we're looking at scramjets and multigenerational probes.

Comment Re:Been there done that (Score 1) 59

Rockets take forever to plan and build, especially at the government level. SpaceX (a lean "startup" company) was founded 10 years ago and just this year started regular commercial service. Boeing, Lockheed/ULA are going to drag their feet for 15-20 years to develop a new launch system.
A 10 year plan is actually ambitious. Space Travel is Hard. The Orion capsule has been a complete disaster, they've been working on it since 2005, and the parachute tests have been such abject failures that they've actually reclassified the test flights to "materials testing" so that it wouldn't be as obvious that their parachute system had failed five times in a row over four years. More recently the "flight ready" capsule failed it's overpressure test (hope the cooling system doesn't fail!) and cracked a bulkhead.
10 years for a new space program is ambitious, right up there with building a new jetliner like the A380 or 747, except that the stakes are much higher. You can't just buy a human rated spacecraft off the shelf (unless you're Russian) and start your own space program (unless you're Chinese)

Comment Re: Um, they used what? (Score 1) 165

If I had to guess, the isotopic version is probably missing or has an extra ion (or two or three), which makes it easier for the ion engine to accelerate it using the same power output. The mass difference is probably negilible, but you could accelerate the same mass using less power (say, 3.5kw instead of 7kw)

Comment Re:Um, they used what? (Score 1) 165

Xenon doesn't have a whole lot of uses here on earth. It's an inert (noble) gas. Ion engines aren't terribly useful for moving living beings around as they wouldn't accelerate an object (and it's life support systems) out of LEO and to Mars before the occupants either starved or died of cancer. Chemical rockets aren't as efficient, but at least they can get you to Mars in under 9 months. A very loose analogy would be crossing the Atlantic in an open 8' rowboat vs flying across in a jet powered 747.

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