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Comment Fixing Number Spoofing is Hard (Score 1) 119

Sure, it's just a simple matter of programming to re-architect the signalling system that's driven the phone companies since the mid-80s. Unfortunately, number spoofing has been an important feature for legitimate businesses - it lets them do things like always give you the number of their main office as caller-id, even if the person is calling from a remote office, or let you give the direct number of the caller, even if the call is getting routed through the company's main office PBX VOIP gateway. It also provides the ability to do a lot more complicated things. And (this mattered more back then than now) it let them run phone switches on processors that were made in the 1960s and 1970s, and with mainframes that might have 10 MIPS of CPU power (compared with the wimpy 1 MIPS VAX I was using in 1980.) My wristwatch probably has less RAM than that, but probably a much faster CPU, and my wimpy Android phone has about as much RAM as my VAX had disk.

And yes, within the next decade we may well have re-architected the world's phone systems away from the designs we used back then (and much of the implementation has changed radically already), but interface standards stick around a lot longer than implementations, and are a lot harder to get rid of.

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

I don't need to stand by the rotation theory. However, the 2.5 degrees that the Earth rotates are about equivalent to the downrange distance.

The first stage is going about 1/5 of the target LEO orbital velocity at separation. While you might well model the trajectory as a parabola over flat ground, given the lack of fuel I would expect that SpaceX puts a lot more care into their trajectory. So far I've failed to attract the attention of the person responsible for Flight Club, the most trusted modeling of SpaceX flights, but I'll message him directly.

Comment Re:I really don't understand this drone applicatio (Score 3, Insightful) 43

My believe is that they intend to fly hundreds of these. If you have 100 tethers from 0 to 60,000 ft or so, I believe that you would have many aircraft accidents. Recall that the British used tethered balloons to protect themselves from German air raids. There is no way that you could see those tethers while flying, until you were very close to them -- then it would be too late to avoid.

There are a dozen or so tethered balloons around the border of the US now, so far there have been no incidents that I know of -- but the border is a place where pilots are very observant. Also, the balloons are only at about 10,000 ft or so, so most planes are far higher.

Comment "Microsoft responds..." (Score 5, Funny) 144

"Microsoft responds..."

We have no idea what would lead Jeremy Archibald Plevin of 2217 Sand Fort Terrace, Blivet Michigan, whose social security number is 555-666-7777, and who only has $9,472 in his bank account and that $100 savings bond his grandfather gave him when he turned 13, and tends to watch an average of 17.3 cat videos per month, and whose favorite search term is 'midget porn' (seriously, Jeremy?1?) to make such unfounded accusations. However, we'd like to assure you, they are unfounded.

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

Well, Alastair, you should probably not get snotty and ad-hominem, unless you want me to comment on how a one-time sci-fi author and the Unix guy at Dish doesn't really have more authority than the random person one might find in the SpaceX group on Reddit.

It happens there are a few people over there who are rocketry professionals, have the math, and have followed SpaceX long enough. So, sure, their opinion can indeed be trusted.

So far, we have a suggestion from one of the lesser folks there that raising the apogee takes advantage of the Earth's rotation. We'll see if we get the attention of the right people.

Comment Re:So what? Radiophobia is the problem, not radiat (Score 3, Informative) 140

Uranium mining is in the noise of todays mining activities, and would remain so even if we stopped mining coal. It can also be extracted directly from seawater, and from rare earth mine tailings which also contain thorium. Nuclear fuel is so energy dense that you barely need any at all; the worlds entire yearly energy demand could be met with byproducts from a single small rare earth mine. The tremendous energy density also puts the cost of the fuel in the noise, and even seawater extraction wouldn't impact energy costs more than a fraction of a cent per kWh.

To mention something so insignificant, you are either ignorant or drinking the green kool-aid. A hell of a lot more mining is needed for wind turbines and solar panels, and neither are remotely environmentally friendly to produce in the quantities needed. Nor do renewables replace fossil fuels, because they are not reliable.

Comment So what? Radiophobia is the problem, not radiation (Score 3, Informative) 140

Radiation killed about 50 at Chernobyl, and none at Fukushima and Three Mile Island. Meanwhile, pollution from burning fossil fuels causes millions of premature deaths every year. Even with a meltdown every year, nuclear would be a vast improvement if it replaced burning of fossil fuels, and incidents are increasingly unlikely with modern reactors, should people let us build them. (If one is objective, nuclear would even reduce loss of life over installation and maintenance of wind and solar generators, and at far less cost.)

The truth is, radiation is typically harmless, and can even be used to improve health. The body has repair mechanisms which routinely deal with an enormously greater amount of chemical damage from oxygen and such. It takes a whole lot of radiation to have any negative health effects, and current regulatory limits are based on bad science funded by fossil fuel interests.

People have been deceived for more than half a century, and mainstream “environmental” organizations such as Greenpeace, Friends of Earth, Sierra Club, NRDC, etc. continue the effort, often funded by those same interests. If you are genuinely concerned about the environment and climate change, look to ecological conservation groups and leading climate scientists, which uniformly support nuclear. It is the only option which is scalable to global needs and also has the smallest environmental footprint.

Learn more about radiation from Scientists for Accurate Radiation Information, or see the articles tagged LNT and Health Effects.

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

It seems to be a common misconception that orbital mechanics somehow knows when you are in orbit and does not work otherwise. But that is as silly as saying that relativity only works near light speed. These things always work regardless of speed, it's just that their effects are macroscopic at greater speeds.

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

Here's an illustration of the boost-back to RTLS trajectory. You can see that it very definitely goes up. And to prove from observation, you can actually see where the two trajectories separate in photos from yesterday's launch. It's a rather dim curl up, and another continuing East, in Jason Ruck's photo and John Kraus's photo.

At the speed of stage separation, they rocket isn't going fast enough to stay in orbit, but it is definitely in the regime where orbital mechanics has a macroscopic effect. If you think about it, this is going to be the case at some reasonable fraction of orbital velocity.

Comment The perspective of a 3D animation professional (Score 5, Interesting) 300

This is just like the way people whined that color film had ruined the medium, and the ones before them who whined about talkies and yearned for the days of silent films.

I started at the NYIT Computer Graphics Laboratory in 1981 and left Pixar in 2000. These days I produce or am on screen once in a while.

While I was at NYIT they weren't story oriented, and thus all you see of them is demos. Pixar, on the other hand, always put story first. We knew that we could not make a film stand up on effects alone.

Today, a good 3D animation house can make absolutely any scene they like. And thus there isn't anything special about doing so. It's there if it needs to be there to tell the story, and not otherwise.

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