

Creating a Pluto flyby using unaligned New Horizons images - misiti3780
http://matthewearl.github.io/2015/08/11/pluto-flyby/?take=two

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rubidium
Very fun project. I love these step-by-step descriptions of little code
projects to see something fun.

For those wondering, Pluto and Charon orbit each other due to their Charon
being 11.6% of Pluto's mass. So it's really a flyby of the center of their
orbit.

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ngoldbaum
Sorry to be pedantic, but all bodies in bound orbits do so around each other.
Perhaps you meant that the center of mass of the Pluto-Charon system is
outside Pluto's surface, so from afar they appear to be rotating around a
point in space between the two bodies.

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icefox
And as we are talking about it do both of them really just orbit around the
sun, but the local gravity cause them to oscillation where one is closer to
the sun before swapping? Locally it only looks like they are orbiting a spot
in space?

~~~
gizmo686
Really, Pluto, Charon, and the Sun are all just orbiting Sagittarius A* , the
center of our galaxy.

[https://en.wikipedia.org/wiki/Sagittarius_A*](https://en.wikipedia.org/wiki/Sagittarius_A*)

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jsingleton
Very nice work! Wasn't the GIF I was expecting but that one is a simulation
with the NASA images texture mapped on
([https://vimeo.com/136223988](https://vimeo.com/136223988)).

I've been using ImageMagick to make GIFs recently and it's great. Only tricky
bit is cropping. If anyone wants to pick up from the end of your article then
I wrote up a guide on my blog: [https://unop.uk/dev/make-animated-gifs-with-
imagemagick](https://unop.uk/dev/make-animated-gifs-with-imagemagick)

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minikites
I can't tell from the writeup, is the animation speed a reasonably accurate
analog of how fast New Horizons passed Pluto?

~~~
kipi
The speed is relatively consistent except for the early frames (where pictures
were taken at twice the rate of later on) and where frames were dropped due to
missing data or alignment failure. Here's a version of the animation where
frame duration is proportional to the real time between the frames:

[http://i.imgur.com/ncTIdHL.gif](http://i.imgur.com/ncTIdHL.gif)

The animation spans 3 months or so. The real time is shown in the text in the
corner.

~~~
spartanatreyu
Fixing your link:

[http://i.imgur.com/ncTIdHL.gifv](http://i.imgur.com/ncTIdHL.gifv)

Using ".gifv" in the link sends a video instead of a gif, way smaller file
size and higher quality animations are better for everyone.

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natep
Very cool! I've forwarded this on to a few members of the NH software team

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thearn4
Excellent use of Python + OpenCV (one of my favorite 3rd party libraries)

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augbot
Excellent! I hope to see myself and others use this for other probe flyby's...
Thank you for opening up the source!

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ck2
All that brilliance but they couldn't set the animation frame rate.

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kipi
I skipped the variable frame rate out of this write-up in an attempt to keep
things simple by leaving the GIF composing to an external program
(ImageMagick). In an earlier iteration I did in fact create a version of the
GIF with frame duration proportional to the real time:

[http://i.imgur.com/ncTIdHL.gif](http://i.imgur.com/ncTIdHL.gif)

