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Perijove 1 (PJ1), August 27, 2016
mcaplinger
post Sep 2 2016, 11:15 PM
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BTW, the map projection in use is a point-perspective from the altitude in the metadata that's always 1600x1600 pixels in size and centered on the lat/lon shown in the metadata. We're still working on the fine pointing calibration so there may be errors on the order of a few pixels absolute and color-to-color.


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Gerald
post Sep 2 2016, 11:17 PM
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After the recent 7/24, here two more relaxing (for me) crops, rendered from the raws, a moon; if I understand right, it should be Ganymede (60 pixels / deg):
Attached Image
And a crop of #06160, showing the bright limb, in contrast to the limb darkening as seen from Earth, and a confirmation from my side of the distinct cloud topography near the terminator (120 pixels / deg):
Attached Image

The limb at the terminator might be of a greenish cast, but I'm not entirely sure, whether this could also be a camera or processing artifact.

Ignoring distance, shape, and rotation of Jupiter, as well as the spacecraft trajectory, didn't cause much misalignment in these images.
Since I didn't reproject the images, you can see the limb close to real.

The images are so fascinating, that I almost forgot to post.
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eliBonora
post Sep 3 2016, 07:04 PM
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I've made my RGB version of JNCE_2016240_00C06160_V01 image



...Emily, thanks for Juno catalog is very usable


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ChrisC
post Sep 3 2016, 10:02 PM
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This thread has the compact and cryptic name "PJ1". YOU all know that means "this is the thread where we process and discuss the results from Perijove 1", but the average reader will not, and may miss this thread entirely as a result.

May I suggest that this thread be renamed "Results from Jupiter flyby Perijove 1 (PJ1)"? I know it's perhaps inaccurate to call it a flyby, but I think it's important to have some sort of words like that in the thread title.

And of course future threads (PJ2, PJ3, etc.) would be similarly named.

MOD: Done. smile.gif
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Roman Tkachenko
post Sep 3 2016, 11:46 PM
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Enhanced and sharpened version of #06182 reprojected to hide a missing part.
Attached Image


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eliBonora
post Sep 4 2016, 07:39 AM
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I add the north (second version) and south poles together



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Gerald
post Sep 4 2016, 04:52 PM
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Heavily compressed and reduced 61-frames gif animation of raw #06160, 100x time-lapsed (5 real seconds per frame, animated with 20 fps) :
Attached Image

That's been a first test run.
The simulated trajectory should be similar to the real one, however with a small discrepancy, which I'll try to fix for the full version.
(credit: NASA / JPL / SwRI / MSSS / SPICE / Gerald Eichstädt)
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xosema
post Sep 4 2016, 08:12 PM
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Hi all.

I'm not sure if this should be posted in this thread... first post of mine, anyway, after years registered. I think it would be didactic to compare Earth with Jupiter in the polar images and then made this (posted in a blog, but I don't know if it would be nice to put url here).

Attached Image


(Credit: NASA / JPL / SwRI / MSSS / NEAR-Shoemaker / Crastinia)
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mcaplinger
post Sep 4 2016, 08:34 PM
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QUOTE (xosema @ Sep 4 2016, 12:12 PM) *
I think it would be didactic to compare Earth with Jupiter in the polar images...

Very pretty, nice idea! To be picky, the Junocam polar image doesn't cover the entire planet since it's a point perspective from a relatively low altitude (it only covers from the south pole to about 30 degrees south) -- so your image is a bit misleading about the scale of things across the planet.

p.s. should be in PJ1 thread. [MOD: DONE.]


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Gerald
post Sep 4 2016, 09:45 PM
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1500-fold timelapse AVI (one frame per real-time minute, animated with 25 fps) of image #06160, again 61 frames, better quality than gif:
Attached File  JNCE_2016240_00C06160_V01_raw.bmp_anim_1500x_timelapse_61frames.avi ( 813.4K ) Number of downloads: 533
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Gerald
post Sep 5 2016, 02:53 PM
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One of my processed south-polar images of Jupiter, derived from raw JunoCam image #06186:
Attached Image

Access to supersampled version with 120 pixels/degree.
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Brian Burns
post Sep 5 2016, 07:39 PM
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QUOTE (Gerald @ Sep 4 2016, 04:45 PM) *
1500-fold timelapse AVI (one frame per real-time minute, animated with 25 fps) of image #06160, again 61 frames, better quality than gif:
Attached File  JNCE_2016240_00C06160_V01_raw.bmp_anim_1500x_timelapse_61frames.avi ( 813.4K ) Number of downloads: 533


This is really cool - will make a great movie once it's complete! smile.gif
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Gerald
post Sep 6 2016, 01:39 AM
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Yes, there is quite a lot in the images waiting for being squeezed out.

Derived from image #06166, an idea of a flyover, each frame rendered directly from the raw:
Attached File  JNCE_2016240_00C06166_V01_raw.bmp_30px_234.5_69500.0_80.84_cx700.0_0_133frames_1140x935.avi ( 764.89K ) Number of downloads: 154

According to the JunoCam paper,
QUOTE
when stereo is available we will encourage the making of visualization products like flyovers.

So the above example shows only the feasability without modeling the cloud topography.

I've too large inconsistencies at the moment to seriously try stereo imaging or methane band analysis.
Via spy.exe I don't get an x-position for the Sun or Earth in the JunoCam frame. So I'm using Jupiter and Jupiter_Barycenter in J2000 and Juno_JunoCam to infer a transformation matrix between a fixed JunoCam pointing and J2000; this provides a transformation from the J2000 trajectory data to my chosen JunoCam frame.
But Jupiter and Jupiter_Barycenter are almost identical, so I might have run into some numerical instability, since the resulting base of the vector space is almost singular.
Another cause for the inconsistencies may be the simplistic spherical model for Jupiter, which is waiting to be replaced by a spheroid.
The third possible cause is, that I'm using preliminary SPICE trajectory data.
To accomodate for the inconsistency, I need to choose the x-value of optical center of the camera dependent of the image, in the above case at x=700, which results in some noticeable rgb misalignment.
I'll begin with reducing my own obvious inaccuracies, and if this doesn't resolve the inconsistencies, I'll check the data sources.
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mcaplinger
post Sep 6 2016, 03:15 AM
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QUOTE (Gerald @ Sep 5 2016, 05:39 PM) *
Via spy.exe I don't get an x-position for the Sun or Earth in the JunoCam frame.

I have to confess I'm not sure what you're trying to accomplish here, but if you're not getting a result, it means that you don't have all of the needed kernel files loaded or they don't cover the time range of interest.


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Gerald
post Sep 6 2016, 08:17 AM
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Strangely, I get y and z-position, but something like "******" for x.
But thanks, verifying the kernels for completeness once more, is a good idea.

I'm trying to convert a J2000 Juno trajectory dump into a trajectory for a JunoCam position and pointing for a fixed instant. My rendering and reprojection algorithms are operating with such a settings. This worked well with EFB using Earth and Moon seen from JunoCam and J2000 as a basis for coordinate transformation from a J2000 trajectory dump to a fixed or variable JunoCam position. I'm just applying some basic linear algebra, a change of basis.


EDIT: (LOL!) I think I've got it:
QUOTE
SET NUMBER FORMAT F18.8

hasn't been able to code the distance Jupiter - Sun. Instead
QUOTE
SET NUMBER FORMAT F20.8

should do it.
Good idea to review the spy script. Looked for missing kernels and found inappropriate number format.

Edit2: At first glance, things make more sense now.
One of the goals I'm trying to accomplish, is reprojecting different raw images to the same perspective, for several subsequent goals. Some of them are
- continuous movies over more than one raw image,
- looking for changes between subsequent images,
- matching cloud topography information from CH4 images with RGB images.

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