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Comment: Re:Hear Hear! (Score 2) 356

by Rei (#48917379) Attached to: "Mammoth Snow Storm" Underwhelms

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) 119

by Rei (#48915031) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

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) 119

by Rei (#48914773) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

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) 119

by Rei (#48914527) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

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:Wow .... (Score 4, Informative) 154

by Rei (#48906547) Attached to: Scientists Determine New Way To Untangle Proteins By Unboiling an Egg

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) 253

by Rei (#48904027) Attached to: Verizon, Cable Lobby Oppose Spec-Bump For Broadband Definition

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.

Comment: Re:What a bunch of A-Holes (Score 5, Interesting) 253

by Rei (#48903903) Attached to: Verizon, Cable Lobby Oppose Spec-Bump For Broadband Definition

Yeah, here in freaking Iceland most people have 50 or 100 Mbps fiber for a lot cheaper than that. And not just in the capitol region, it even runs out to Vestfirðir now where the largest city is under 3k people.

It makes no sense whatsoever that a hunk of rock just under the arctic circle, 3 1/2 hours plane flight to the nearest land mass with any sort of half-decent manufacturing infrastructure, consisting often unstable ground constantly bombarded by intense winds, ice, landslides, avalanches, volcanoes, earthquakes, floods, etc, with the world's 2nd or 3rd lowest population density and heavy taxes on all imported goods, can do this while the US can't. What the heck, America? You've got half of the world's servers sitting right there, why the heck can't you manage to connect people to them?

Comment: Re:Insurance (Score 4, Informative) 204

by Rei (#48898643) Attached to: Calif. DMV Back-Pedals On Commercial-Plate Mandate For Ride-Share Drivers

That falls into statistically normal usage. Being a commercial driver absolutely does not. Statistically, a commercial driver drives way more than a noncommercial driver, and they're much more likely to be sued, and for more money. It's absurd to argue that they should be able to drive on insurance rates calculated for statistical norms of noncommercial drivers. If you allow that sort of ignoring of statistics then you might as well get rid of all statistical tables period and charge every last person the same rate for all types of insurance.

Comment: Insurance (Score 4, Insightful) 204

by Rei (#48898577) Attached to: Calif. DMV Back-Pedals On Commercial-Plate Mandate For Ride-Share Drivers

Why, exactly, should Uber drivers get to drive passengers using regular non-commercial drivers' insurance? Commercial insurance costs more because people who drive people around for a living are much more likely to cost the insurance companies more money. If you're letting them drive on non-commercial licenses than that means that regular drivers are subsidizing Uber-drivers.

Comment: Re:Svavar Knutur and Marketa Irglova - World burns (Score 1) 144

by Rei (#48876341) Attached to: Doomsday Clock Could Move

Svavar Knútur is great... the music's really pretty, but between songs he's a standup comedian. ;) That said, some of his songs are funny too... one of his songs (in Icelandic) is about a guy on his way to propose to his girlfriend when he gets bitten by a zombie, and he meets up with her and is trying to propose while slowly turning into a zombie and increasingly wanting to eat her instead... but it turns out that she was bitten by a zombie too, so they end up living happily ever after ;) Oh, and then there's this song.

Comment: Re:Who they do not attempt to stay relevant? (Score 4, Funny) 144

by Rei (#48873505) Attached to: Doomsday Clock Could Move

If Earth becomes Venus-like then those with innovation and drive will innovate a way to protect themselves, while those that don't will eventally adapt, growing a hard, rocky skin and blood based on liquid metals rather than water. The climate has changed in Earth's past and life survived; if our future is to be a tribe of hideous rock monsters ruled by clever, pitiless human overlords in protective bubbles, then bring it on. It's not a reason to hinder economic growth.

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Vote freedom. Vote prosperity. Vote Reanimated Corpse Of Ayn Rand in 2016.

New York... when civilization falls apart, remember, we were way ahead of you. - David Letterman

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