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.
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.
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.
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.
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.
To return to landing site it goes UP, back, and down. Orbital mechanics.
East takes you out, out takes you west, west takes you in, in takes you east, port and starboard bring you home.
You can't change the angle at which the scene is rendered by interpolating between frames.
It's not the raw framerate. It's that the scene your viewing has to match where you're looking that quickly or you get motion sick.
While the parent is Anonymous coward, please rate him up, as that is correct.
"When in doubt, print 'em out." -- Karl's Programming Proverb 0x7