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Comment Re:Hear Hear! (Score 2) 397

Ah, Americans and their "mammoth snowstorms" - try living on a rock in the middle of the North Atlantic. You know what we call a snowstorm with gale-force winds and copious precipitation? Tuesday ;) Our last one was... let's see, all weekend. The northwest gets hit by another gale-force storm tomorrow. The southeast is predicted to get hurricane-force winds on Thursday morning.

Here's what the job of someone dispatched to maintain antennae for air traffic control services has to deal with here. ;) (those are guy wires)

Comment Re:Visible from Earth? (Score 1) 126

A sun-like star is about 1 1/2 million kilometers in diameter. To blot out all light from such a star that's 10 light years away, a 0,75 kilometer diameter disc could be no more than 1/200.000th of a light year, or around 50 million kilometers (1/3rd the distance between the earth and the sun).

The brightest star in the sky is Sirius A. It has a diameter of 2,4 million km and a distance of 8.6 light years. This means your shade could be no more than 25 million kilometers away.

The sun and the moon both take up about the same amount of arc in the night sky so would be about equally difficult to block; let's go with the sun for a nice supervillian-ish approach. 1,4m km diameter, 150m km distance means it'd be able to block the sun at 800km away. Such an object could probably be kept in a stable orbit at half that altitude, so yeah, you could most definitely block out stars with the thing - including our sun!

Comment Re:keeping station behind it? (Score 1) 126

It makes sense. We can radiate individual photons for thrust if so desired. We can move individual electrons from one position in a spacecraft to another for tiny adjustments of angle and position if so desired. It seems you're going to be much more limited by your ability to precisely track your target than by your ability to make fine adjustments.

I think a much bigger problem is going to be isolating standing waves from within the shielding material from distorting its perfect rim (with a shield that big and thin, there *will* be oscillations from even the slightest thrust inputs). You need to isolate the rim from the shielding. And you also need to make sure that you can have a rim that can be coiled up for launch but uncoil to such perfection in space.

Tough task... but technically, it should be possible.

Comment Re:No (Score 3, Insightful) 126

I would presume that the bulk material in the inside has no need for accuracy, only the very rim. The question is more of whether you can have a coiled material that when uncoiled (deployment) can return to a shape with that level of accuracy. I would think it possible, but I really don't know.

I would forsee a super-precise rim with just a small bit of light shielding on its inside, deployed via uncoiling, and then attached to a much stronger, less precise uncoiled ring to which the bulk shielding material (and stationkeeping ion thrusters) are attached. The attachment between the two would need to provide for vibration and tension isolation (even the slowest adjustments in angle of such a huge, thin shield are going to set in motion relevant vibrations, you've got almost no damping - you want the structural ring to deal with those and not transfer them through to the precision ring). Not to mention that your shield will be acting as a solar sail whether you like it or not (unless you're at L2... but then your craft better be nuclear powered).

Your telescope behind it is going to need to do some real precision stationkeeping (either extreme precision on the whole spacecraft positioning, or merely "good" positioning of the whole spacecraft plus extreme precision adjustment of the optics within) . This means long development times and costs to demonstrate that you can pull it off before you actually build the shield. But I would think that also possible - just very difficult. If they take the latter route they could probably demonstrate that here on Earth, which would be a big cost-saver.

Comment Re:You nerds need to get over yourselves (Score 1) 212

When people say coding is the new literacy they are not suggesting that everyone become professional programmers anymore then saying someone should be able to read and write means they should become professional writers.

Exactly. Go back a couple of hundred years and you even have well-off people saying 'I don't need to learn to write, I can afford to hire a scribe'. You had people saying 'not everyone needs to learn to read and write, there aren't enough jobs for that many scribes anyway'.

Before he retired, my stepfather was the head groundskeeper on a golf course. Not exactly the kind of job you think of as requiring coding skills. Except that they had a computerised irrigation system that could trigger sprinklers in response to various events (humidity sensors, motion sensors, time, and so on). It came with a partly-graphical domain-specific programming language for controlling it. It's going to be very hard in the next 50 years to find a job that doesn't require some programming to do it competently - even this kind of stereotypically low-tech job requires it now.

Comment Re:grandmother reference (Score 4, Insightful) 468

It's really the only viable answer to piracy that's left and publishers are embracing it wholeheartedly.

I used to pirate games and I used to buy games. I eventually couldn't be bothered with pirating and worrying about malware or with trying to jump through the hoops that the publishers wanted, so I stopped playing games altogether. Then gog.com launched and sold me games that I was nostalgic about, cheaply. Then they started selling newer games. I spent more with them last six months than I did on total on games in the five years since Steam was launched and the industry wend DRM-happy. I can download DRM-free installers for all of the games, often in OS X, Windows, and Linux versions.

It turns out that there's another answer to piracy that works: sell your product in a way that's easy to use at a reasonable price. Stop worrying about pirates and start worrying about customers. Someone who wouldn't buy your game anyway who pirates it is not a lost sale, but someone who can't be bothered to put up with your treating them like a criminal and so doesn't buy from you is. Buying a game from gog.com is easier than pirating and, if you factor in the cost of your time, probably cheaper as well.

Give me a product I want for a reasonable price and I will happily hand over my money, because I feel that I'm getting something valuable in return. Don't, and... well, computer games are not the only form of entertainment available.

Comment Re:"A hangar in Mojave" (Score 3, Informative) 38

That's actually what it's like at "Mojave Spaceport". Hangers of small aviation practicioners and their junk. Gary Hudson, Burt Rutan, etc. Old aircraft and parts strewn about. Left-over facilities from Rotary Rocket used by flight schools. A medium-sized facility for Orbital. Some big facilities for BAE, etc. An aircraft graveyard next door.

Comment Re:Wow .... (Score 4, Informative) 155

It's a two-step process. The first is a chemical that dissolves the proteins (still in their "cooked" folding), and the second is some sort of centrifuge or similar (they don't go into details on the device in the article) that subjects the proteins to very high sheer strain, effectively mechanically unfolding them so that they can then relax back into their natural state.

Not exactly a spice you can sprinkle onto your steak, but still pretty neat. :)

Comment Re:America is HUGE (Score 2) 255

That just raises another issue - why are you services and utilities so unreliable in the US? Here in Iceland we get hurricane-force winds several times a year on average - I've had gusts over Cat 5 on my land. Winter isn't incredibly cold but is super wet (all precipitation forms), windy, and lasts a long time. Up at higher altitudes you get stuff like this (yes, those are guy wires... somewhere in that mass). I lived in the US for a long time and had an average of maybe two power outages a year from downed lines and such - sometimes lasting for long periods of time. I've never once had a power outage here that was anything more than a blown breaker in my place.

It's really amazing what you all put up with - your infrastructure standards are really low.

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