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Comment Re:They already have (Score 1) 667

Bruce,

Do you think it's possible in this 'big data' age to come up with an absolute, reasonably accurate, energy budget for the planet? We have storms, and shifting ocean currents, and a number of things that affect the temperatures that are easy to measure; but the net energy is surely growing as inexorably and smoothly as the CO2 concentration.

Now, of course, those kind of facts won't matter to people whose bread is buttered with oil money. Still, it could be useful for tracking our progress or lack thereof.

Comment Not strictly true (Score 2) 300

I've done some research into hypersonic technology, and it's not strictly true that hypersonic flights are necessarily less efficient per passenger mile. Sure, up to this point it has been the case, but we haven't explored in detail.

The US currently has tested a hypersonic glider that goes a heck of a long way, with a surprisingly good glide ratio, above Mach 20. Apparently it was to glide for thousands of miles, while only descending maybe 20 miles, implying a tremendously high glide ratio, over 100:1. If that's true, then you could have extremely efficient flight at Mach 20.

These "waverider" planes use radically different aerodynamics, so the old rules don't apply. They're nothing like the Concorde.

Comment Re:Typical "Big Lie" (Score 4, Informative) 75

Do you honestly believe that the banks are selling credit card info, and that apple isn't sharing any of that info with anyone?

I don't know if the banks are selling credit card info; but I know that merchants are. Apple Pay prevents them from doing that, which is one of the big reasons that so many merchants in the US have stopped using NFC for payments, as this earlier Slashdot story describes.

A friend of mine was deeply involved in NFC payments at significant companies (not Apple) and says that not only is Apple not sharing the info; they can't. It's just not available. The NFC chips in the phone don't send out identifiable information.

Comment Typical "Big Lie" (Score 5, Insightful) 75

What the banks are really concerned about is not that Apple is collecting information, but that their customers will realize the opposite -- that using Apple pay is far more secure than other systems. If people start waking up to the fact that all of the information merchants are getting from credit cards can and will be used against them; then systems like Apple Pay are going to destroy the status quo.

What better way to try to stop this then by spouting a Big Lie? The banks are saying that they are worried that Apple is collecting too much information. If they can seed doubt into customers for long enough, then they may succeed in killing it.

Comment Why is encryption not standard? (Score 1) 90

It's astonishing that all communication is not encrypted. If you are sharing information over a common carrier, you should expect that somebody is going to be grabbing and examining the bytes.

So, somehow, it is just not the norm to encrypt communication. One reason might be that during the eighties and nineties as the internet was going wide, ITAR and patents on systems like RSA made people and companies nervous and unwilling to go there; that was definitely a missed opportunity.

Perhaps another problem is that there's no money to be made in encryption; and there are real (small, but real) costs in establishing it.

Still, though...

Why is there no encrypted "WhatsApp"? It would not be hard, it would be trivial to deliver through Google Play, and there would be a immediate market. If the connections were truly peer-to-peer, the infrastructure to support it would be almost zero.

How has the world convinced people not to encrypt all communication?

Comment Re:two bounces (Score 1) 223

1) There is/was a significant risk that drilling would push Philae off the comet again. Still, it's a risk worth taking; without the solar recharging ESA has only until Saturday before the batteries run out.
2) The challenge is that either the lander is on its side, so the solar panels can't see the sun; or that the lander is up against a wall blocking the sun most of the time. They are considering possible ways of reorienting Philae; but it doesn't seem too likely. Also, without the harpoons or ice screws, it's likely that Philae will be pushed into space by gasses escaping the comet as it gets closer to the sun; so the extra sunlight is a double-edged sword.

Comment Re:two bounces (Score 1) 223

It is fascinating that you can see stars and the comet surface at the same time; it shows how far from the sun they are. In no pictures from the moon can you see any stars.

Right now the spacecraft is about 3x as far from the sun as the moon is from the sun, so the sun is only 1/9th as bright there. I suppose the cameras might have a bit more dynamic range than the film cameras of the late 60's. The comet nucleus might also be quite dark, but the moon is very dark as well (about 10% albedo.)

Comment two bounces (Score 5, Interesting) 223

Philae bounced twice, the first bounce was about two hours, the second one 7 minutes. If the gravity on the comet is 1/200,000th that on earth (a reasonable estimate, it varies around the comet because it's *way* not round) then the first bounce was about 1,000 feet off the surface, but the second one was only about three feet. Seven minutes to fly up and down three feet; that's almost impossible to imagine.

Comment Re:should be banned or regulated (Score 1) 237

In a city like NYC or perhaps London, I agree that the number of daily rides is a pie that will be subdivided differently. In a town like Los Angeles or even San Francisco; not so much. The number of Uber rides in LA will exceed the pre-Uber number of taxi rides soon, if it hasn't already -- it's a real game changer. Many more people are taking Uber rather than taxis, yes -- but even more people are taking Uber than used to drive.

In LA, the taxi service will suffer; but also (and maybe more so) the rental car business. It's cheaper to UberX around the city (especially if you use mass transit when you can) than renting a car; and more convenient too because you don't have to worry about parking.

Comment Exactly the opposite! Enhances Public Transport! (Score 1) 237

I use Uber in Los Angeles; as many people do.

Los Angeles has very limited subway service. It exists, it's pretty quick, but it doesn't go too many places. So, I use Uber to get to and from the subway stops closest to where I want to go; and use the train for the bulk of the transport.

Now, if I was going with a group of people instead of by myself, I'd Uber the whole way; the subway charges per person and Uber per car. But for traveling by yourself; Uber and mass transit is a great combo.

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