
How to Land the Space Shuttle from Space [video] - cyrusmg
https://www.youtube.com/watch?v=Jb4prVsXkZU
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satysin
That guy is a very good presenter IMHO. Amusing but not overly so, engaging
and made great use of visuals.

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burnbabyburn
yeah but the camera guy could have done a better job, I got motion sickness.

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_archon_
I feel like the rotation clamp was too firm, and perhaps the camera could have
had a mass on a torque arm to give it more angular inertia. This was SUPER
distracting early in the presentation before the presenter was scaled down.

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funnyfacts365
The video description says it was the autofocus...

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joekrill
This was great! I love coming across great, short talks like this that
elaborate on a very interesting problem that laypeople like myself would never
otherwise have even known existed.

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dingaling
Accordingly Shuttle pilots and commanders are honorary members of the WWII
Glider Pilots' Association. Mach 14 or 80 knots, it's the same principle!

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mikeash
In the soaring community, we sometimes refer to the Shuttle as the world's
highest performance motorglider. The power-off glide ratio is absolutely
atrocious, though.

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danbruc
What surprised me the most, the difference between being in orbit and starting
to reenter is only 362 km/h but it takes a three minute burn to decelerate
which I guess is a 0.5mv² thing with big m and huge v.

EDIT: My intuition was wrong, this has nothing to do with a large kinetic
energy due to a large velocity.

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mikeash
The reentry burn is done with the teeny little OMS engines rather than the big
main engines. If you look at the back of the Shuttle (such as
[https://i0.wp.com/amazingstoriesmag.com/wp-
content/uploads/2...](https://i0.wp.com/amazingstoriesmag.com/wp-
content/uploads/2014/05/Space-shuttle-main-and-OMS-engines_a.jpg)), the OMS
engines are the two little ones in the upper corners. Once you're in orbit,
there's usually no hurry to make changes, so you don't need much acceleration.
For getting _to_ orbit, you want to stop fighting gravity as fast as possible,
so powerful engines are a must.

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danbruc
Tiny is pretty relative [1]. I expected them to be more powerful and -
mistakenly - thought the small acceleration is due to the large kinetic energy
due to the large velocity.

[1] [https://en.wikipedia.org/wiki/AJ10](https://en.wikipedia.org/wiki/AJ10)

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mikeash
Right, rockets provide the same acceleration regardless of speed, since
there's no way for the engine to "know" how fast the vehicle is moving.
Acceleration is basically exhaust velocity times mass flow divided by vehicle
mass.

With an 84cm diameter and weighing about 200 pounds, I'm OK calling them
"tiny."

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danbruc
I missed that, I only looked at the image and there it looks way more massive
and larger than what the dimensions table says. Even taking into account that
the image depicts an entire stage and not just the engine, 0.84 m and 100 kg
is a lot less than I would have expected or guessed based on the image.

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mikeash
Agreed. I first saw the image and thought wow, that really is big. Then I saw
the specs.

I guess it's misleading because the engine is much closer to the camera than
the background, but nothing makes that obvious. There's a tiny little person
behind it, and if you don't realize the perspective difference, that would
look like the engine is pretty huge.

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tonylemesmer
TLDR seriously impressive stats given in an engaging, amusing, rapid fire talk
by Bret Copeland, pilot

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azdle
If I wanted to make a presentation like that what tools would I need to use?
That was way more engaging than a powerpoint presentation. It almost seems
like an animated video that pauses itself rather than a slideshow.

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jedimastert
It really is just a series of animations. It's basically a time lapse of
drawing. You can look at how Henry from MinutePhysics does his videos[1] (and
if you like how this presentation is done, I _highly_ recommend looking into
MinutePhysics). These were probably done in something similar to flash. For
open source programs, I'd probably look at Synfig[2] or Pencil2D[3].

[1]
[https://www.youtube.com/watch?v=GhZ3naSgJg4](https://www.youtube.com/watch?v=GhZ3naSgJg4)
[2] [http://synfig.org/](http://synfig.org/) [3]
[https://www.pencil2d.org/](https://www.pencil2d.org/)

