PyVoyager

PyVoyager automatically creates and stabilizes Voyager flyby movies - the eventual goal is to produce a single movie with titles and audio as automatically as possible, with each planet and target having a separate segment.

• About
• Project Status
• Example Movies
• Trajectories
• Sources
• Contributing
• Usage
• Install
• Technical
• History
• License

About

Voyager 1 and 2 sent back over 70,000 images, so there is a lot to explore!

Unfortunately the cameras were not able to point very accurately at their targets, resulting in jittery image sequences. PyVoyager centers the target planet or moon in the frame, and creates movies from the image sequences.

Project Status

The program is currently at version 0.6 - there are still a lot of things to do!

Example Movies

Here is an example image sequence, followed by the centered version -

Here is Voyager 1's approach to Ganymede, partially colored -

And here is Voyager 1's approach to Io, partially colored - any mini 'volcanoes' are actually leftover from the removal of reseau marks (a grid of black dots) -

Here is a movie of Voyager 1's Jupiter flyby (3 mins), mostly false color, v0.47 -

https://www.youtube.com/watch?v=lYUgU-Bc1_w

And there is a playlist with several movies here -

https://www.youtube.com/playlist?list=PLxP4UgQGtMiLvyKjT7BQ-ht905VvNSaFP

Trajectories

Trajectory plots are calculated using the spacecraft and target positions, as provided by 'kernel' files -

See data/trajectories for all of them.

Sources

Images were obtained from the Planetary Data System (PDS) - https://pds-rings.seti.org/voyager/iss/. They provide four types for each image:

• RAW - the original 800x800px raw images, with reseau marks. 8bit
• CLEANED - same as above, with reseau marks removed. 8bit
• CALIB - above, with flatfield subtracted. 16bit
• GEOMED - the above, with geometry corrected via reseau marks. 16bit

You can see each of them in the following animation:

Contributing

Although the goal is to complete the movies in as automated fashion as possible, there are still places where manual intervention is required -

• Some frames don't get centered correctly due to noise, or being on the edge of an image, etc., so they need to be manually centered by editing the db/centersOverride.csv file, or (eventually) using the vg center <imageId> <x offset>, <y offset> command.
• Centering needs to be manually turned off at close approach and back on again at departure - this is done in db/centering.csv.
• Multi-target images often need to be relabelled to the largest target in the image (or whatever the centering routines center on) - this is done in the db/retargeting.csv file.
• Close-up composite images need to be manually aligned - e.g. the closeups of the clouds of Jupiter, by editing the db/composites.csv file. The weight of the different filters can also be adjusted there.
• Movie frame rates need to be adjusted so interesting images stay on the screen longer - this is done in the db/framerates.csv file.
• And eventually, mosaics would need to be specified manually in a db/mosaics.csv file.

There are also more technical tasks listed in the Trello board here.

Usage

For more on how to use the program, see USAGE.md.

Install

For more on how to install the program, see INSTALL.md.

Technical

For more technical details on the algorithms used, see TECHNICAL.md.

History

For the program and movie version history see HISTORY.md.

License

This software is released under the MIT license - see LICENSE.md.