In August of 2014, Anthony Wesley from Australia was invited to the Saturn Science Conference to give a presentation of the current state of high-resolution planetary imaging of Mars, Jupiter, Saturn and Uranus by amateurs. He included our film in the presentation and it got a lot of attention from planetary scientists—among them Glenn Orton from NASA’s Juno mission spacecraft team. Glenn has worked for many years with some of the leading amateur planetary institutions to set up a collaboration between pros and amateurs for the Juno mission, and I was invited to to be part of this project.

Amateurs have made great progress when it comes to high-resolution planetary photography in recent years thanks to their dedication, sophisticated hardware and software but also a big evolution of their technical skills and experience.

So I decided to start a new animation project. This time I planned to use the best images of Jupiter taken by amateurs from around the world, most of which were already uploaded and easily accessible on the world's major dedicated forums like ALPO-Japan and PVOL.

With the help of John Rogers (Director of the Jupiter section at the British Astronomical Association), Ricardo Hueso (PVOL, the Planetary Virtual Observatory and Laboratory), Marc Delcroix (Director of the Planetary Section at the Société Astronomique de France) and Johan Warell (President of the Swedish Amateur Astronomical Society), we contacted some of the best amateur planetary photographers from around the world to get the permission to use their images taken in 2014 and 2015 for this project.

Jupiter rotates in just less than 10 hours, which is quite fast. For any given position on earth, an observer might take pictures of good quality for a total of three to four hours per night when it is high in the sky. All in all, they will show a good amount of detail on 50 to 70 percent of the planet’s total surface. Weather conditions permitting, it is possible to cover the remainder of the surface the following night as Jupiter has rotated two-and-a-half times during that period.

But, if the astronomer misses this opportunity, it might take four or more days to get complete coverage of the surface, and many features will have evolved quite a lot during that period. This makes it difficult to correctly piece the images together. The main weakness of the “Voyager 3” project was that we were all in the same geographical spot, so when we got two weeks of bad weather it almost put an end to our project. By using morphing techniques I was eventually able to fill in the gaps in the timeline and solve the problem.

For this new project, we had the participation of 91 planetary photographers representing 22 countries from all around the world, contributing more than 1,000 images for the period between the 19th of December 2014 and the 31st of March 2015.

With such an extensive network, Jupiter would, at least theoretically, be visible at all times and we should be able to get some images for every rotation, which would make for smooth transitions without having to resort to morphing. This was highly optimistic, of course, and in reality I was able to put together a high definition map for every second day on average, which corresponds to five rotations of Jupiter.

After collecting the images, I had to rename them so they would conform to a standard format with the exact date and time. I then sent them to Johan Warell and Christoffer Svenske, who transformed each image into a cylindrical projections using the free software Winjupos. It can be compared to a world atlas showing a flat representation of our earth.

Upon receiving these projections back, I arranged them in chronological order and introduced date separations representing the transit time of the Great Red Spot. In this way I had a very precise visual feedback of which images composed every rotation of Jupiter.