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Creating a Pluto flyby using unaligned New Horizons images
- rubidium 11y agoVery 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.
- ngoldbaum 11y agoSorry 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.
- icefox 11y agoAnd 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 11y agoReally, 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*
- thearn4 11y agoExcellent use of Python + OpenCV (one of my favorite 3rd party libraries)
- augbot 11y agoExcellent! I hope to see myself and others use this for other probe flyby's... Thank you for opening up the source!
- minikites 11y agoI can't tell from the writeup, is the animation speed a reasonably accurate analog of how fast New Horizons passed Pluto?
- idlewords 11y agoEach orbit of Pluto and Charon around each other takes 6.4 days. This is speeded up by a factor of a lot.
- minikites 11y agoThat makes more sense, I read quite a few articles emphasizing just how fast New Horizons was going so I got carried away.
- kipi 11y agoThe 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.
- minikites 11y agoNeat, thanks for sharing this!
- spartanatreyu 11y agoFixing 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.
- ck2 11y agoAll that brilliance but they couldn't set the animation frame rate.
- kipi 11y agoI 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
- jsingleton 11y agoVery 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
- natep 11y agoVery cool! I've forwarded this on to a few members of the NH software team