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LIGO works by measuring the distance between two tracks set at right angles. A passing gravitational wave would momentarily change the length of one leg or the other, or both, in characteristic ways.

It measures the distance with a laser beam. It splits the beam, and sends them down the two tracks. They bounce off mirrors, and when they return, they interfere. Changes in the length will change the interference. That means that they can detect changes at distances on the order of a single wavelength of light.

That's an interferometer, the I in LIGO. At its core, it's the same thing that Michaelson and Morley used to look for aether, and failed to find it. The trick is that this has to be even more sensitive, because the expected changes are even smaller and the contraption itself is much bigger (4 km, versus a few meters). They have to exclude all kinds of potential interference, from passing trucks to earthquakes.

I suppose it may well go "ping" when it spots a gravitational wave, and they'll end up comparing it to other experiments. But they'll get more than a ping; they'll get a signal of the changing lengths that they can use to map the size of the wave, and even a hint of its direction.

It's not just us. Plato raised this as a general problem in ancient Greece. Good people-- the kind of people we should want to be in a position of power-- are quite possibly never the people who are lusting to put themselves into a position of power. That's the one-sentence summary of "The Republic".

You know what? Books contain an even greater potential for spoilers. Yet I bet you don't typically flip to the last chapter and read that before reading the rest of the book. Yet those who do probably do so because they want to. Just like no gamer would dive into the source code unless they had a reason to.

For some reason, he didn't head off to Newfoundland; he went at tropical latitudes. If he was trying to follow a line of latitude due west to Asia, he was going the VERY long way. If he hadn't bumped into something along the way, he'd have been deeply screwed.

The direct route from Portugal to Japan would have taken him northeast. He probably had suspicions that the northeast passage wouldn't work, but the further north he went, the better. He'd have been better off going to Newfoundland. He would have failed to find the northwest passage, but he couldn't know that, either.

The explanation that he thought it was smaller would account for that. If he was going based on his suspicion that there might be something that far south, he had little evidence to support it, and was really staking his life it. It certainly paid off in spades, but that could easily have been a lie he paid for with his life.

I saw a 'gator right at the edge of the VAB parking lot last month. In a drainage ditch, up to the fence, cars parked right on the other side.

With luck, they'll start incorporating our radio transceivers. I hear that SpaceX flies with several USRPs now, so that's not completely unrealistic. That might be as close as I can get. Anyone who can get me a base invitation, though, would be greatly appreciated and I'd be happy to do some entertaining speeches while there. I need a base invite for Vandenberg, too. I got in to the official viewing site for the first try of the last launch (and that scrubbed too), but this next one is on Pad 6.

I was in Florida to speak at Orlando Hamcation and went to see the DISCOVR launch at Kennedy Space Center. I paid $50 to be at LC-39 for the launch, an observation tower made from a disused gantry on the Nasa Causeway between the pads and the Vehicle Assembly Building. A crawler was parked next door! A hot sandwich buffet, chips, and sodas were served. It was cold and windy! I watched for a few hours and unfortunately the launch scrubbed due to high stratospheric winds.

The next day, Delaware North Corporation, which operates tourism at KSC, decided not to open LC-39 or the Saturn 5 center for the launch. This was the third launch attempt and I guess they decided most people had left. I was annoyed.

The closest beach was going to be closed in the evening, it's a sensitive ecological area. I ended up seeing the launch from Jetty Park. This turned out not to be such a great location, the tower wasn't visible at all and the first 10 seconds of the rocket in flight were obscured before we saw it over a hill.

What's a better viewing location?

See, I was right. Stubborn, stupid, and there's no point in arguing with you.

If I email you from my Google account, where do those bits go? Who can read it once it leaves Google's servers? I don't know, because aside from SSL in transport, it's not encrypted.

Maybe you should think for 30 seconds before posting.

I, for one, don't really use Google+, but it's not because of any particular problem other than, "No one else is using it," with just a smidge of "I don't know what I'm supposed to be using it for," thrown in.

It does seem to me like "Hangouts" should be its own thing, along with chat and VoIP. If anything, those things should should sooner be integrated into Gmail somehow. I'm not sure I want that, but it would make more sense, at least, since it's all, roughly speaking, private communications.

I also think that there should be a separate web application that is, "Where my phone automatically uploads my photos, where I can organize them and track them myself, but they're private." Personally, it just makes me a little uncomfortable for that to be bolted straight on to the "photo sharing social networking site," but maybe that's just me. I'm old. I feel ok if the social networking site can connect in and pull photos from the private site. Hell, even if I know it's all ultimately stored in the database, that's not what bothers me. It's just to have my private stuff be in the same interface as the publicly shared stuff, without a clear apparent distinction... it worries my poor little monkey brain.

Ultimately, between Facebook, Twitter, and Google+, I tend to use Facebook for sharing posts/photos/updates. Not because I like it or think it's good, and only somewhat because my friends seem to use it more. As much as anything, I think it's because it's the site that confuses me the least.

There's not much point in arguing with you because you've shown that you're both too stupid to understand the point and too stubborn to actually think for 30 seconds before pushing your own tired nonsensical point.

But here's the thing in a very basic, simple, easy to understand explanation: End-to-end encryption doesn't suddenly become useless because you've trusted a 3rd party with the encryption keys. When you trust a 3rd party, then the encryption remains as strong as that 3rd party is trustworthy.

This is especially important to know, since we're already trusting other 3rd parties as part of the security chain. If I don't trust GPG or anyone auditing their code, then I can't trust the security of things encrypted with GPG, regardless of who has the keys.

Regardless, encrypting individual messages rather than relying solely on SSL during transmission does add security against various kinds of attacks and breaches. I could give examples, but do you want them? Would examples help, or are you, as I suspect, simply being difficult because you're an asshole who can't admit to being wrong?

Ah, so I guess the answer is, "a little of each."

Not needed if you've ever heard of Donald Knuth's reward checks, something that I'd expect most Slashdot readers have.

To clarify, I think it's pretty obvious to anyone who isn't dumb, and isn't being intentionally obtuse, that Gmail does not provide the level of security I'm suggesting.

So I guess the question is, which are you? An idiot, or an asshole?

Who said those were the things that I wanted?

AFAIK, Gmail uses SSL for its connections, but the messages don't have any special additional form of encryption beyond that.