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Comment Re:Might want to read the fine print... (Score 4, Interesting) 163

This is fine - they're not pretending those impacts don't happen, they are just not what they're studying. They are asking "What does the fallout do to people some distance from the accident?"

The exposure people get early in the accident and very close to the reactors depends hugely on the nature of the accident. At Chernobyl, there were many firefighters within meters of an exposed critical core, resulting in a large toll from acute radiation sickness. At Fukushima, the cores ceased to be critical seconds after the quake and tens of minutes before the tsunami, and radiation was only released days later, so there was no acute radiation sickness.

By contrast, the effect of the fallout is much less dependent on the nature of the accident, just on how much radioactive material was released*. It can sensibly be studied without specifying details of how the accident happened.

* There is some dependence: the relative quantity of short lived isotopes such as Iodine-131 in the fallout depends somewhat on how long the radioactive material was contained prior to release.

Comment Re:I don't do "social events" (Score 1) 136

I remember an occasion back when phones were first becoming popular, when I was at a hamburger stand and there were five girls in a nearby booth. Four of them were talking on the phone, and the other was sitting looking incredibly bored. It really struck me at the time - why go out with friends and spend the time yakking on the phone?

Comment Causation? (Score 5, Insightful) 87

The more niche your research topic, the longer the title has to be to describe it, and correspondingly the fewer people will be interested. Compare, for example, "A New Hierarchy of Phylogenetic Models Consistent with Heterogeneous Substitution Rates" with "The Origin of Chemical Elements". While one will be much more cited that the other, the reason isn't the title length.

Comment Re:I would laugh but that's too much effort (Score 4, Insightful) 253

The fastest DSL is slower than the worst cable connection Comcast or Charter can make

DSL is also available in some areas that cable markets won't serve. My parents' house 10-12 miles outside of the area served by any cable company, but they get DSL just fine, and trust me 3Mbps may be slow by today's standards but it sure as heck beats dial-up.

My brother lives just a little further out and even the DSL isn't available. His only options are dial-up (worthless these days), satellite and cellular. The latter two have bandwidth caps that make them very undesirable - particularly to his 7 year old who is used to streaming Netflix at her mom's house.

Comment Re:We had one, it was called the Shuttle. (Score 4, Informative) 71

For the cost of one shuttle launch you could more than pay for SpaceX's entire development program so far. For two launches you could pay for their development so far plus the extra they'll need to finish the Dragon capsule and "man-rate" the system, and still have some money left over for a couple of launches (each of which can carry as many crew as the shuttle.)

(I'm taking the cost of a shuttle launch as about $1.5B. Lower values can be argued for, adjust the above as needed for your preferred cost.)

For a few more shuttle launches and a several year wait, Blue Origins would likely be able to field a man-rated rocket, if you want multiple space taxi companies to chose from. ULA could do it too, but that would probably cost you ten shuttle launches.

The shuttle was hideously expensive and needed to go.

Comment Re:Bullshit (Score 1) 105

It isn't clear to me whether they collect heat and use some heat engine, or whether they use a small area of high cost high efficiency high temperature photovoltaic cells. As I've complained elsewhere, the articles provide almost no detail. There is mention of cooling water, but either possibility could use that.

Comment Re:No details (Score 2) 105

You'd use differential GPS. Wikipedia says this has accuracy of 10cm in the best case. Whether that is good enough for this application I'm not sure. Given that affordability is a big part of their goal, if they were taking this approach they'd not attach a GPS to each mirror, but rather have two receivers that they used for a callibration stage and then wouldn't be needed again unless something shifted. You'd need to know orientation as well as location for the mirrors.

I doubt this is what they're doing, but who knows.

Comment No details (Score 4, Informative) 105

TFA is lacking in details about how this works, but if you follow the link you get to a Guardian article which is lacking in details, but links to the projects website which excessively uses gratuitous Javascript and is lacking in details.

They talk about "plonkability" - that the mirror structures can just be plonked on the ground and will 'just work'. This suggests to me that somewhere in their system is some intelligence or calibration which is able to notice where each mirror is relative to the target and adapt its pointing accordingly. Their photos show the target tower having two rectangular surfaces pointed towards the mirrors. I suspect the plane white surface is there to aid mirror pointing calibration in some way, but I don't know.

Comment Re:almost 40 million (Score 1) 705

Two things:

1. An account isn't necessarily a unique person. One person may have 5 accounts if they change emails every now and then.

2. This is an international site, not an American site (actually even the company itself is Canadian). Those 40 million members are taken from the world's ~7 billion person population, not the United States' ~320 million.

Comment Re:Yes (Score 2) 687

I work for a municipality (and actually, on the property tax software). If you don't pay your taxes (for several years - a tax auction doesn't occur for a 1-year delinquent property) it is forcibly sold at auction . . . and you get the proceeds - after the taxes are taken out.

And even then you still have a year to reclaim your property from the buyer as long as you can pay the taxes plus 3% of whatever their bid for the property was.

Don't confuse the concept of ownership with things having requirements. You live in a modern society - we collect property taxes (or at least some places do), and we have to have a means to get people to pay those taxes. If we didn't, no one would bother.

The goal of science is to build better mousetraps. The goal of nature is to build better mice.