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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:how enforcable (Score 1) 635

That's kind of the point though. an old tractor that is in good shape is not cheap. The farms that are still around now tend to be the ones that have good accounting practices, and work to avoid taking on bad debt. (bad meaning debt where the terms are not a good deal)

I grew up in an area where a lot of the farms are gone now, a lot of them went bust in the 80's. Too much debt. Many of them still live on houses attached to the same farm properties, but their farms are owned by big companies now. Some ended up working for the corporations, others gave up farming entirely. Sometimes progress is sad.

Comment Re:how enforcable (Score 1) 635

Having a corp to manage the financial risk of operating a farm is a huge advantage to most farmers. Ultimately farmers want to have a stable reliable income for their family, which was not something that was really that possible with the older family owned farms. I'd much rather drive a corp owned combine and have them deal with the financing than have to raise capital to buy a new one every time it needs to be replaced.

Comment Re:Missing Info (Score 1) 635

There is already precedent set for that. Nobody gets sued because the circumvention is at fault. Someone would have to prove that the machine was unsafe even with the sensor, or that there was a manufacturing defect that caused a problem with some other unrelated failsafe.
There is some line between where the manufacturer has responsibility and the operator has responsibility. And while you can open a civil case over nearly anything in the US, winning is another matter.

Comment Re:Missing Info (Score 3, Insightful) 635

I don't think farmers are trying to mod their tractors. I think they are trying to repair them without going to John Deere. Which means the tractor is probably out of warranty. Farmers are really cheap people and if they still had some free repair warranty service available to them they'd be using that instead of screwing aroud with hacking into their tractors.

While it would be nice if this just goes to court and somehow weakens the DMCA. I suspect that congress will just write up a quick and dirty exception for the ag lobby and slap a band-aid on the problem to make the farmers happy.

Comment Re:Lots of bad assumptions here. (Score 1) 1124

If a little robot unloaded your cart and packed them into bags that might be nicer than racing through with rfid tags. I think a lot of people don't use self checkout because most people don't want to do all the work themselves of scanning and bagging, it's kind of a hassle. And like you said, grocery delivery is an option, and that might be the way people do things in the future. Paying online means no cashiers either. But it seems extremely like that a human driver would have to do the deliveries.

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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