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Comment Fixing Number Spoofing is Hard (Score 1) 120

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: 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: 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) 301

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.

Comment The wave of the future (Score 2) 255

In a world of autonomous machines, people and animals are squishy bugs. If this sounds extreme, consider how it is actually the case in the world of automobiles, and how previous to that the risk was horse carriages. We can make devices good at not running over people, but never perfect.

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