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Comment: Brightness (Score 2) 67

by Dan East (#48918397) Attached to: Kepler Discovers Solar System's Ancient 'Twin'

They calculated that there are 5 planets orbiting the star by the way the intensity of the star dips very, very slightly in a pattern. Are we sure there are no other mechanisms that can cause the star's intensity to vary in a pattern? We only know about our own star's sunspots, and the longer term cycle (11 years) in which the sunspots change the intensity at which it emits. How do we know that a smaller, much older star doesn't have a sunspot type cycle that is shorter or more complex, and that is what is causing this star's intensity to change?

Comment: Re:"A hangar in Mojave" (Score 3, Informative) 38

by Bruce Perens (#48908157) Attached to: Virgin Galactic Dumps Scaled Composites For Spaceship Two

That's actually what it's like at "Mojave Spaceport". Hangers of small aviation practicioners and their junk. Gary Hudson, Burt Rutan, etc. Old aircraft and parts strewn about. Left-over facilities from Rotary Rocket used by flight schools. A medium-sized facility for Orbital. Some big facilities for BAE, etc. An aircraft graveyard next door.

Comment: Not quite (Score 5, Interesting) 388

we are likely to end up in an ethically worse position than we were before.

Actually, no. In order to do the more involved things, "physical observation, bugging rooms, and breaking into phones or computers", they have to get a warrant. This ups the ante and they must present a convincing argument to the judge for the need to surveil the people in question. This increases oversight, expense, and the human resources required. That means less shotgun approach and more focused surveillance only where needed.

With digital communication they felt entitled to capture any information they wanted, since there wasn't an obvious physical intrusion. Obviously they could not handle this in a responsible manner, and thus our free society is making the necessary adjustments. So that's just too bad for the spies. Sorry.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48897151) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

There is no reason that we have to pick one and abandon work on the others. I don't see that the same resources go into solving more than one, except that the meteor and volcano problem have one solution in common - be on another planet when it happens.

The clathrate problem and nuclear war have the potential to end the human race while it is still on one planet, so we need to solve both of them ASAP.

Comment: Re:Hold your horses (Score 4, Interesting) 210

by Dan East (#48890799) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

Actually I have to correct myself. I assumed it was low voltage, like a single cell battery, and thus around 1-2 volts. That's not the case - the voltage is around 2,000 volts:
http://www.sharingtechnology.n...

That means my calculations were off by a factor of 1333. So if you divide the times I stated for AA and D batteries by 1,333 and you'll get a more accurate figure. So even a deep cell 12 V battery, which is around 120 watt-hours, could only run the bell for 9.5 years. Guess that makes it more impressive than I thought.

Or my calculations are still way off.

Comment: Hold your horses (Score 1, Informative) 210

by Dan East (#48890727) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

Let's put this in perspective. The only "amazing" thing here is simply that the chemicals used in the battery are very stable. The amount of energy we're talking about is very, very low.

FTA, it takes around 1 nanoampere to ring the bell once. It rings around around 2 Hz. Thus it takes 2 nanoampere a second, which works out to 7200 nanoampere-hours.

So let's see how long a AA battery could run that bell. The better AAs produce 3 amp-hour of power. That is 3000000000 nanoamperes. 3000000000 / 7200 gives us 416,666 hours, which is 47.56 years. So if we could somehow spread the power of a AA out over time so the chemicals didn't break down, it could power that bell for 47.56 years. A single D battery has 12 amp-hours of power (4 times that of a AA), thus it could run the bell for 190 years.

We're not talking about much power whatsoever - simply that the chemicals and construction of the battery are such that it has not degraded that much just through time alone.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48887305) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

Sure, there are going to be mediating forces in the environment. Melting is an obvious one. The positive feedbacks have been getting the most attention because they are really scary. It appears that there are gas clathrates in the ground and under water that can come out at a certain temperature. The worst case is that we get an event similar to Lake Nyos, but with a somewhat different mechanism and potentially many more dead. The best case is a significant atmospheric input of CO2 and methane that we can't control.

I don't think I have to discount Trenberth. He's trying to correct his model, he isn't saying there is no warming.

Comment: Re:Good news (Score 5, Interesting) 420

by Dan East (#48886691) Attached to: Disney Turned Down George Lucas's Star Wars Scripts

His plots aren't all that bad. His screenplay (especially dialog) is weak, and his directing is of a very specific style that only works with certain kinds of actors. It is both those things that hurt the prequels.

As far as directing, Lucas is a hands-off director. He doesn't give the actors feedback or direction - he expects them to bring the characters to life and flush out the nuances on his own. So what he'd do is shoot a scene over and over, even though the actors thought they got it perfectly right, until some nuance or personality came out that seemed more natural and unique. He always said he did his directing in the editing room - but to do that he needed a big pool of material to work with to pull the good stuff out of. With Hamill, Fisher and Ford, they had the talent, energy and personality to simply bring the characters to life. Do you think we liked Han Solo so well because Lucas directed Ford to be that exact character? Or Princess Leia being such a strong female lead and showing playful disdain in the harsh tone of her voice towards Solo? Lucus just stepped back and let them create.

That directorial style worked well in American Graffiti too. Like the liquor store scene. The robber leaves the store and throws the bottle of liquor to Terry. They shot it over and over, and every time he caught it perfectly. Until finally, he turned around too late and just barely caught it with the tips of his fingers. That was what Lucas was waiting for, and that's what made it in the movie. At the very beginning, where Terry runs his Vespa over the curb and hit the wall - total accident, but Lucas kept the cameras rolling and that made it into the movie.

So when it comes to most kids, like Jake Lloyd, they NEED coaching and prompting and directed. I strongly believe that Jake Lloyd was awful in Phantom Menace because of Lucas' directing style. When I watch him in other movies, like Jingle All the Way, I'm reminded that he was pretty talented for his age - Lucas just didn't bring that out because he just sits back and watches with no obvious emotion or constructive feedback.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48884865) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

Thanks.

McKitrick is an economist out of his field. Trenberth and Fasullo cite many of their other papers and the publications to which they were submitted, but it seems mostly not accepted. But their conclusion seems to be that there were other times in recent years that the rate of warming decreased for a time only for it to return to its previous rate. I only see the abstract for Kosaka and Xie, but they state "the multi-decadal warming trend is very likely to continue with greenhouse gas increase."

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48882193) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

I imagine that the major financial companies make this part of their economic modeling. Most of them do publish weather-related and climate-related advisories regarding commodity and company price trends, etc. How detailed do they get? The wouldn't tell and I am the wrong kind of scientist to ask. Can we make a government or public one? Yes, the level of detail is the big question.

Comment: Re:They already have (Score 1) 666

by Bruce Perens (#48882135) Attached to: US Senate Set To Vote On Whether Climate Change Is a Hoax

Oh, do I have to qualify that for you, like the hottest outside of a period of Milankovitch Forcing? Gee, maybe the Earth's orbit changed, like back then, and we just didn't notice.

Let's take a look at one of the references you cited:

A section of a draft IPCC report, looking at short-term trends, says temperatures are likely to be 0.4 to 1.0 degree Celsius (0.7-1.8F) warmer from 2016-35 than in the two decades to 2005. Rain and snow may increase in areas that already have high precipitation and decline in areas with scarcity, it says.

It sounds like we have reason to be alarmed.

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