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Comment Re:Off-Earth habitation (Score 1) 684

10m of silicate ceramic; 30cm of iron. A hull, in that order from exterior to interior, is all you need to get radiation shielding comparable to what you get on Earth's surface. If you build a torus or cylinder more than ~1km in diameter, you can spin it for Earth-normal gravity, something you can't get on a planet. You could even make parts of the hull clear; just use 10m of fused quartz, 1m of either water or poly-carbonate, and 30cm of aluminum oxide instead. All the bulk materials could conceivably be mined on the Moon and launched into orbit electrically with mass drivers. You could power it with large solar arrays. If you use multiple levels inside, you get rather huge surface areas to populate. Just beware of colony drops.

Comment Re:Even this is wrong (Score 1) 684

All space stations to date have been regularly resupplied from Earth. The ISS can only go six months without being resupplied before it has to be abandoned. Because of fun things like mass fraction, you can't send something the size of the ISS to Mars. Interestingly enough, you can send something much bigger. But there's no way in hell we'll build one. For one thing, it would technically be illegal to put nukes in space.

Comment Re:Is Computer Science Education Racist and Sexist (Score 1) 612

First, "Hindu" is a religion, not an ethnicity. The term you're looking for is either desi or South Asian. Second, you don't understand what the term "minority" means within a sociological context. It's not a measure of population; it's a measure of power. The opposite of a minority group isn't a majority group. The opposite of a minority group is a dominant group. Third, there is a well studied effect where men see a group that is 17% women as being half women. And groups that are 30% women as being majority women. I'm betting that's what was going on with you.

Submission + - Here's why Windows 8 is crap, and how it wasted my time for nothing. (

lagi writes: With Windows 8 to be released soon, I'm sure some slashdot windows users (as primary OS) asked them selves, "Is it time to install some nice Linux distro and dodge the pain?" Well, after using Windows 7 since it was released and trying the Windows 8 RC for over two months, i came to a conclusion, it's defensibly the time! After all, I did the same when Windows 98 came out, so i didn't feel the pain of neither ME or XP, and Windows 2000 was great as secondary system.

I don't like Windows 8 and i don't want "Metro" start screen or however it's called — the old start menu worked slow and nicely, I don't want pointy window corners (or at least wanna have the ability to choose), don't need a slow Task Manager that looks too much like "System Monitor", don't need 3487 types of dialog interfaces, don't need a "cool" progress bar that shows copy progress but never shows the right time, don't want MS to take over my facebook account and not let me unbind it and I certainly don't want to pay any money for something i don't own (especially when I can have Linux for free).

I decided installing Fedora 17 on my new SSD, and connect Windows HD to SATA slot #2. I'm actually using Mageia 2 @ work, and it's really nice and works kinda well, but I always liked the RedHat way, been using it's flavors since 98~. so after being very disappointed from Fedora (15-16) and Gnome 3 combination, i wanted to give it another try. I downloaded the 600MB~ Live image, put it on USB, and installed Fedora, from within Fedora, the whole process including configuration screens took less then 30 min, no errors, all devices detected including my unknown wifi adapter, and my machine fully booted in 10 secs without any tweaks, and Gnome 3.4 is actually not so bad, I was super happy.

Until I tried rebooting back to Windows.
Fedora installed GRUB2 on MBR of the new disk (Windows 8 boot option was added automatically pointing to sdb1), of course when i chosen it Windows went insane, "like wtf you're doing ?!!", and rebooted my PC right away.
I figured out the install didn't configure GRUB right for win8, so i manually change bios boot back to windows hd, booted again, without asking anything it went into this strange "automatic repair" mode... asking me if i what restore to last point? ... well i said "no!", cause i didn't understand what it will actually do ... but it started preforming repairs anyway... I have no idea what it was doing to my poor (non-SSD) hd for like 30 min, when it finished (?) an encouraging message was displayed saying "sorry, we couldn't repair your system" with just one option "shutdown" ... so i did. then i booted again, and just like i expected, windows booted up just fine like nothing happened.


Submission + - NASA "Mohawk Guy" To Host Radio Show (

An anonymous reader writes: NASA’s “Mohawk Guy” Bobak Ferdowsi, a flight director for the Mars Science Laboratory mission that lowered the Curiosity rover to the Martian surface in early August, will host a two-hour online broadcast on Internet radio station Third Rock Radio at 4 p.m. EDT, Thursday, August 30.

Comment Injecting Some Facts (Score 1) 1184

The average gasoline internal combustion engine is only 20% efficient. That is to say, only 20% of the energy present in the fuel-air mix at ignition is reclaimed as mechanical energy by the engine; the rest is lost as heat. A further 90% of the energy harnessed by the engine is used to keep the engine itself running; pumps, belts, fans, and transmissions all take energy to run. That means only 2% of the energy present in the gas tank makes it to spinning the wheels. And that's with the air off! So you can see, there's a lot of room for improvement. Turbo Diesel engines are half again as efficient than a gasoline engine of the same weight. If every gas engine were swapped for a Deisel engine, the US could stop oil imports from all other countries except Canada. And that's just going from 2% efficiency to ~3%. If you were to add gas turbines in the exhaust system to capture some of the waste heat, essentially making a multiple-expansion engine, you could easily tripple or quadruple current mileages. Combine such an engine system with and electric powertrain, like the Chevy Volt, and regenerative braking and you could have a 100MPG car within the decade. All using existant technology. So don't tell me a 54MPG fleet average is unattainable. If it was, the car makers themselves wouldn't have agreed to it.

Submission + - Is a nuclear fuelbank a good idea? (

An anonymous reader writes: Another roundtable at the Bulletin of the Atomic Sciences explores the notion of nuclear fuel banks: offer nations a guaranteed supply of low-enriched uranium if they renounce the right to enrich on their own. So far, two articles have been published in the roundtable.

Submission + - NASA uncovers millions of new black holes in space (

coondoggie writes: "NASA today said its Wide-field Infrared Survey Explorer satellite has unearthed a "bonanza of newfound supermassive black holes and extreme galaxies called hot DOGs, or dust-obscured galaxies." NASA said the latest discoveries help astronomers better understand how galaxies and the behemoth black holes at their centers grow and evolve together."

Submission + - Einstein proved correct again (

Coisiche writes: Observation of a pair of white dwarfs in a tight orbit provide further supporting proof for Einstein's gravity waves. Given how well his theories have held up to tests you have to wonder how anyone could have thought that CERN's superluminal neutrinos would be anything other than experimental error.

You don't have to know how the computer works, just how to work the computer.