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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:Haha (Score 1) 183

No, but as I mentioned, my dad was ticketed for accelerating through a light too fast. Went to court with him (9 YO) to fight it. Judge says "I know that (short) light" and tossed it out; less than one minute. Though sat through hours of listening to other cases; domestic violence over cereal boxes, brushing teeth with whiskey (DUI excuse), etc. Eye opening for a 9 YO to see dregs of humanity.

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 Re:Lots of bad assumptions here. (Score 1) 1127

Like the garbage man, the cashier will be reduced. Home Depot and Walmart grocery stores are mostly self checkout now. Costco tried the self checkout but them removed them. So maybe not go away, but easily 90% reduction. I'd rather have a grocery cart full of RFID tagged goods, then just walk by a reader and checkout instantly. Then again, my usual grocery store offers free delivery for orders over $100, so that created a job for a picker and driver, and didn't cost me anything, actually saves me time.

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