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Comment Re:It could have been a much bigger media event (Score 1) 279

The explosion would be detected by a Defense Support Program satellite, but it would lack the double flash typical of nuclear detonations, so the military would probably not be seriously alarmed. People on the ground in SF on the other hand might have a little scare.

It could be much more serious if this happened over a less developed country possessing nuclear warheads but not the advanced detection equipment the US has, especially when its forces were on high alert. In June 2002, one such incident were just a few hours from happening. A meteor exploded over the eastern Mediterranean with the force of a small atomic bomb. Had it arrived some three hours later, it would have exploded over the border between India and Pakistan, when those countries had their nuclear forces on high alert. Since those countries probably do not have advanced detection equipment like the DSP mentioned above, they could have believed that the other side had launched a nuclear attack, and launched their own weapons in "retaliation".

Comment Re:Darn that dirty hydrogen (Score 2) 406

Hydrogen has many uses that do not rely on being able to store it. For example, the Sabatier reaction combines hydrogen with carbon dioxide in the presence of a nickel catalyst to produce methane and oxygen. And methane is the primary component of natural gas, so I'm sure that you can see why that is useful.

Hydrogen can also be used together with carbon monoxide in the Fischer-Tropsch process to create liquid hydrocarbons, which could be used as synthetic petroleum. In other words, another very advantageous use of raw hydrogen without the associated problems with storing the raw hydrogen gas.

Comment Re:500 megabytes? (Score 3, Interesting) 328

But, since the byte is really the smallest meaningful unit of data is a byte (yes, a single bit can represent a boolean value, but you can't transmit a single bit; in the simple case of a modem, you would generally transmit a byte; with modern networks, you transmit a packet, and I believe the smallest amount of data you can encapsulate in a packet is also one byte, isn't it?), data speeds should really be measured in *bytes* per second.

I disagree. There are several reasons why data transfer capacities of network equipment is measured in raw bits per second. First, different encoding schemes use different numbers of bits to transmit one byte. Second, at what layer do you want to measure the byte transport capacity? Do you wish to use the frame payload, the IP packet payload, the TCP stream payload, or something else? Third, even with a set encoding scheme and a defined layer, different packet sizes will give different amounts of overhead and thus differing data transport capacities for the same raw bitrate. Transmitting a stream of packets with a one-byte payload results in much more overhead and much lower payload transfer rate than if you use packets carrying 1 kb of payload. Fourth, features of various protocols significantly affect transfer rate. For an example compare the transfer rate of TFTP and FTP on the same network.

Comment Re:Religious Freedom (Score 3, Interesting) 358

Actually, they do. In Sweden, hate speech is illegal except if you do it because of your religion. A few years ago, a pentecostal pastor said that gays were "a cancer in society". He was charged with hate speech and convicted, but the conviction was overturned because freedom of religion trumps other laws (including laws against hate speech) in the EU.

There have been other instances. Last year, a muslim man was applying for a job at a company. At the interview, he refused to take the hand of the female boss while shaking the hands of other men. When the Swedish Public Employment Service because of this incident concluded that this man didn't make a reasonable effort to get a job, they retracted his social security payments. He complained to the public anti-discrimination board and they filed suit against the employment service, charging that he had been discriminated against because of his religion, a court case which they won. That he himself had discriminated against the female boss because of her sex was obviously considered irrelevant, as religion and multiculturalism apparently trumps equality between the sexes in Sweden.

Comment Re:Vapor? (Score 1) 283

How much energy would be needed to capture and convert enough CO to fill a car's gas tank?

CO only exists for a short while after it has been released into the atmosphere. When it has mixed with air, it fairly quickly reacts with the oxygen in the air to form CO2.

Comment Re:why not just more solar? (Score 1) 415

Meanwhile we have deserts that are receiving orders of magnitude more solar energy than the world currently uses, that could be harvested using technology we have today.

It could work in the US, which has its own deserts. But do you really think that we in Europe want to give Muammar Qaddafi and his neighbors a big red on-off switch for our entire electricity grids? We cannot rely on these unstable states, which means that we must generate our own power.

Comment Re:Good thing we dont have Electric Cars yet (Score 1) 464

Other than the generator and battery, nothing electric of any importance.

I'd call running lights pretty important, especially where I live (see below).

Push-start or roll it down a hill, pop the clutch, and you're driving the next 800 miles passing all the cooked cars.

Only in daylight, which in December/January lasts roughly from 9 am to 3 pm here in Stockholm, Sweden. When it is dark 18 hours each day, you need lights.

Of course, in the summer the reverse happens. In June/July, dawn is roughly 3 am and dusk is roughly at 10 pm, and the sky isn't completely black even in the middle of the night.

Comment Re:Good thing we dont have Electric Cars yet (Score 1) 464

I'd hate to see what would happen if all our energy usage was electric instead of burning stuff.

So you think your car doesn't use electricity? Ever heard of spark plugs, starter motors, instruments, electric fuel pumps, electric cooling fans, lights, not to mention electronic engine control units? There are hundreds of electrical systems in a car.

Comment Re:Remarkable (Score 1) 109

though it will use a bit to counteract the tiny atmospheric resistance that exists even at that altitude

I'd say that it probably doesn't have to use any fuel for that. The ISS is at a similar altitude, and it is boosted to a higher altitude a few times a year, but the ISS is intended to stay in orbit for a long time. Since the X-37B is only intended to stay up for nine months, it is possible that it does not need any boosting. Besides, it is also possible that it can minimize the drag by using a certain attitude profile, such as pointing the nose forwards. If horizontal w.r.t. the ground (inverted or not), it might even be able to use its wings to counteract the aerodynamic resistance, like a glider.

Comment Re:Self-limiting (Score 1) 299

I'm no expert, but I believe it is quite possible to track nukes' origins based on their radioactive signatures. This was done in "The Sum of All Fears". (Yes, I know it's a movie, but Clancy is known for better realism with such details than your average scriptwriter.)

I read the book, and the method seems reasonable, so I see no reason why it shouldn't be possible. It is highly likely that different plants around the world will generate material with slightly different isotope ratios, thus enabling the tracing of the material if a sample could be obtained from each plant. But even if (as is highly likely) hostile states refuse to give you a sample, a sample from just friendly states would be better than nothing, since then you could rule out those as sources.

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