JunoCam "Marble Movie", July 10 through October 14 Options

[Gerald]

Parts 8 and 9 of Marble Movie level-2-processed, stills and AVI animation, including a synopsis of the 40 first Marble Movie images after PJ1.
Youtube version covering parts 7 to 9, pre-, and post-PJ1.

[Gerald]

Re-rendered level 1 "Marble Movie" images around PJ1, as zips, and as online browsable version. Some of those images have been cropped in previous renditions.
Part 7 images have been supersampled about 4-fold, part 8 supersampled about twice.

[Brian Burns]

Parts 8 and 9 of Marble Movie level-2-processed, stills and AVI animation, including a synopsis of the 40 first Marble Movie images after PJ1.
Youtube version covering parts 7 to 9, pre-, and post-PJ1.

These are cool.

Would it be possible to have them slow down near closest approach also, so you could see the details (as in the earlier animation you made)?

I've been using ffmpeg to assemble movies, and had to adjust the frame rate by adding duplicate frames - the number of copies of a frame is based on the size of the target times a constant, with some limit, which seemed to work fairly well. It's less realistic of course, but it lets you see the detail in the images, and speeds past the more distant images. I had to use mklink (on Windows) to make symbolic links so I didn't run out of space on my hard drive with thousands of copies...

[Gerald]

I've already done so with a few Marble Movie images close to PJ1, also with ffmpeg (see a few posts above, post #84), and I'm currently working on the second external 2TB HD drive.
But I've not yet included Jupiter's oblateness and axis obliquity. Trajectory data are in J2000 like Earth's axis, and Earth is almost spherical, so these two effects didn't need to be considered for Earth. I'm working on both effects, first axis obliquity.

[Gerald]

The method I'm using to retrieve axis obliquity seems to return reasonable results now:
 mable_pre_pj1_c6157_c6159_51_out.avi ( 610.38K ) Number of downloads: 202

It uses pointing vectors from Jupiter to Earth and Sun in JUPITER_IAU and J2000 frames of SPICE trajectory data as obtained via spy.exe to calculate the change of base transformation, which has been missing before. I'm using two vector pairs for a fixed instant to calculate Jupiter's axis. Jupiter's assumed angular velocity is some estimate near 2pi / 9h50m expressed in units of JunoCam's interframe delay of about 0.38s.

Jupiter's yet unconsidered oblateness is likely to contribute most of the remaining inaccuracy. I'm working on fixing this.

[Gerald]

JunoCam Marble Movie, part 10, level 1 stills, and level 2 AVI.
Part 10 covers September 4 to September 10, 2016.

[Gerald]

John Rogers at the British Astronomical Association provides an enhanced and annotated version of the immediate pre- and post- PJ1 Marble Movie images.

[Gerald]

Level 1 stills of Marble Movie part 11 are available.
The sequence starting at image #7913 required some parameter adjustment, therefore I've split part 11 in two zip files with a slightly different naming convention (substrings '11', resp. '11a').

Rendering of level 2 images for AVI update is running.
I'll add the video update to the same URL later today, I'd think less than an hour from now, and edit this post accordingly.

Edit: The AVIs are uploaded. Part 11 is split into two fragments, and I've provided the full sequence from parts 1 to part 11.
Part 11 covers September 11 to 17, 2016.

[Gerald]

For a seamless animation of rendered JunoCam images near PJs, to be able to look for, or to measure changes, or to create good map products, I'll need to model Jupiter as a spheroid. Thus far I've implemented only a sphere.
One of the core capabilities is intersecting a line with the target object. Until recently, I didn't find the time to write up these geometric basics as a pdf document. But now, as things are going to get more complex, it became necessary to do so.
 junocam08_basic_geometry_I.pdf ( 565.69K ) Number of downloads: 737

I'm now going to implement the spheroid part.

[FOV]

I just watched the marble movie with headline banner "Citizen Science: Juno Fan Creates Movie of Spacecraft's Approach to Jupiter" on the NASA web site home page. I really enjoyed it. Great stuff.

[elakdawalla]

Level 1 stills of Marble Movie part 11 are available.

These are, belatedly, posted on my marble movie page.

[mcaplinger]

I'm now going to implement the spheroid part.

See SPICE toolkit function surfpt for the triaxial ellipsoid implementation.

[Gerald]

Thanks! I thought, I've seen it somewhere in SPICE.
But I'm expecting the need to extend it to a model of a dynamical cloud top (and possibly some rudimentary extension towards polytropes) to improve the predictive capabilities, and I might require the derivatives for approximation methods.
So I think, I'd better understand the inside of the black box.

[xflare]

I haven't been able to find the Dates and Times of the upcoming Perijove close approaches, does anyone have them?

[Phil Stooke]

Not times, but dates:

http://www.planetary.org/blogs/emily-lakda...om-junocam.html


(just go to the Planetary Society website and enter 'juno' in the search box)

Phil