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Comment Re:Speed wasn't SR-71's problem. (Score 1) 299

I believe you're thinking of the U-2, which was shot down twice. On 1 May, 1960, over the Soviet Union, and 14 October, 1062, over Cuba.

No SR-71s were ever lost to enemy fire, although they were certainly shot at. The North Vietnamese shot over 800 missiles at it, without scoring a hit.

No, he is right. The USSR did develop a missile capable of downing an SR-71. It was the S-200, also known as the SA-5 Gammon (NATO code name), which entered service in 1966. Now, none of these actually shot down an SR-71, because the U.S. had the good sense not to put an SR-71 within range of one while over-flying Soviet territory.

The S-200/SA-5 was a 2.5 km/s (Mach 7-8) missile able to engage at an altitude of 40,000 m, versus the Mach 3.3 and 26,000 m limits of the SR-71.

Comment Paratyphoid Fever Killed the Aztecs (Score 5, Informative) 131

It is true that the bacterium discussed in the Nature, Evolution & Ecology paper discusses is of the genus Salmonella, but describing the disease that killed the Aztecs as being "salmonella" conveys the wrong information to the lay reader (or even the scientifically informed one) since this term is commonly used to describe food borne disease. There are several different pathogenic bacteria species, and subspecies, in the genus Salmonella. The infectious form of Salmonella enterica that is transmitted person-to-person is a different sub-species from ones that cause food poisoning and in this form is known as Paratyphoid Fever (similar to the related Typhoid Fever).

Comment Re:Need a replacement for Lithium (Score 2) 172

An AC making stuff up. What else is new?

Allowing for an 80 kWH battery (Tesla's have 70, IIRC), each EV would use about 20 kg of lithium. A 2011 study found 39 million tons of economically recoverable lithium (at current prices). This is enough to build 2 billion EV cars (there are only one billion cars on Earth right now), or 4 billion EV cars if we go with 40 kWH batteries.

So there is enough proven lithium reserves at current prices to replace 200% to 400% of all cars, not "5%".

But note that "at current prices" bit. The "lithium reserve" estimate is very soft on the upper end. We know there is at least 39 million tons of economically exploitable lithium. But unlike oil it has not intensively exploited so many worldwide resources are likely undiscovered or underestimated. And as is true of many resources, modest increases in price will likely greatly expand the reserves. We can afford to spend more for that 20 kg of lithium (currently costing $180).

Comment Re:Can the power grid support it? (Score 1) 172

The entire power grid is going to need, and get, an upgrade over the next few decades as the old model of selling electricity from centralized power plants to individual homes goes the way of the horse and buggy. Introducing motor vehicles required an entire nation-wide road upgrade.

Yes, a major grid upgrade for the 21st Century needs to be planned and executed, but it is not a reason for not deploying electric vehicles, and renewable energy. But electrical grids require maintenance and upgrades on a regular basis anyway. Although some transformers that are in service are as old as 70 years, most have a service life of 25-30 years, with increased rates of failure marking its end. Over the next 30 years nearly all power transmission transformers are going to be replaced anyway.

Comment Re:State Exercise? (Score 2) 227

Scaring the crap out of everyone is considered "a state exercise?"

It was a mistake by state officials, plain and simple.

My interst is that I would want to know where the thing is aimed for, so I could stand a few miles away and enjoy the show. Radiation poisioning isn't pretty, and to actually witness the explosion, then get quickly incinerated seems like the ticket.

Knowing where to be in Hawaii to see a nuclear attack, and not be injured, is easy to figure out.

If North Korea is dropping one its new 250 kT warheads on Hawaii (which could possibly be a 500 kT design), they will be dropping it on the Honolulu/Pearl Harbor urban/military complex. They are cheek by jowl and regardless of the actual aim point, the entire area will get devastated. 72% of Hawaii's entire population lives on Oahu (a total of 950,000 people in the island) and 81% of those live in or near the Honolulu urban area.

According to NukeMap site (airburst option) such an attack with a 250 kT warhead on downtown Honolulu would kill about 215,000 and injure 155,000, thus making 40% of the population of Oahu (and 30% of the entire state) as casualties. If the military complex at Pearl Harbor is targets then "only" 40,000 would die, but 180,000 would be injured.The worst case, a 500 kT warhead on Honolulu would kill 265,000 and injure 175,000.

An attack would likely be an airburst (which produces the most blast and thermal radiation damage) and which produces no local fallout. Even if a ground burst the tradewinds blow steadily to the south-west, to west and blow the fallout away from the rest of the island.

So the place to be is somewhere on Oahu that is outside of the southern coastal strip, and you will want to be at least nine miles away from its detonation point. This would put you outside of the thermal burn range (even for first degree) even if its yield is 500 kT. So most anywhere on the north half of the island will be fine.

Comment Re:Only 2 words?? (Score 1) 228

Zulu: itiye Lithuanian: arbata Samoan: lauti Malagasy: dite Polish: herbata Maltese: corto

I am guessing that you plugged "tea" into Google Translate and looked it up in all the languages (since I found all of these languages on Google Translate when I went to check).

It is evident that Lithuanian and Polish are the same word -- the equivalent of "herb" (from the Latin herba).

Comment Re:Non story (Score 5, Interesting) 341

They're not doing enough, quick-enough and what happens in Cape Town could be a model for what is inevitably going to hit California eventually if they don't start working on better solutions.

Some areas of California (Santa Barbara), which depend on local water supplies (like Cape Town) have faced this problem before (SB built a desalinization plant in the 1970s). Localities that depended on local ground water supplies have been hit by the drought, and required alternate supplies. But California is a big state. Scattered local problems do not add up to a general problem for California

In general California was plenty of water for its cities and towns, which only use 20% of the available water but produce 98% of its GDP. Agriculture, that use 80% of the water supplies only 2% of the GDP. So simply paying off farmers not to grow something can supply all of the urban water California will ever need.

The number one agricultural user of water (22% of all agricultural water usage) is a crop - alfalfa - that provides so little value that it often costs more to deliver the water than the alfalfa crop is worth (and 2/3 of that crop is simply exported to Asia), ancient water rights from the 19th century are the reason for this subsidy. Paying off all the alfalfa growers not to grow anything would only cost 0.1% of the state's GDP and double the amount of water available to the cities.

Comment Re:Non story (Score 2) 341

Desalination is a problem for large-scale use; it's highly energy intensive, and you're left with hypersaline brine, which is environmentally destructive.

Every thing has problems in large-scale use. Proper planning and engineering can manage and solve problems though.

Highly-energy intensive, compared to what? Current technology can turn seawater into fresh water with 2.5 kwh per cubic meter. A typical desktop PC can consume 125 watts average power consumption, so less than a day of the PC sitting there turned on can provide a cubic meter (264 gallons).

The brine output does need to be managed properly, and it is possible to do it badly - but it is also possible to have to problem at all, if the output is suitable diluted before discharge.

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