Combining data from many perijoves, For images/mosaics that are not perijove-specific Options

[Bjorn Jonsson]

This thread is for images/mosaics that combine data from more than one perijove pass or compare data (e.g. the appearance of specific features on Jupiter) from two or more perijoves. In other words, it is for images and related stuff not specific to a single perijove.


It is possible to use the JIRAM infrared images to attempt to guess what areas not imaged by JunoCam might look like at visual wavelengths.

Below is a montage showing versions of a mosaic of JunoCam images from perijoves 1, 3, 4 and 5. The effects of the varying global illumination have been removed. The mosaic shows Jupiter's north polar region in orthographic projection from directly above. Because the north pole is in darkness, an inverted, heavily processed and colorized JIRAM mosaic was used to fill the gap at the north pole. This represents an attempt to guess what this area might look like in visible light. Small scale details in the cloud morphology should be fairly accurate/realistic but the overall contrast, brightness and color are based partially on a visual comparison of the JunoCam and JIRAM data farther from the pole where useful data from both instruments is available. It is difficult to guess how accurate this is but it is definitely far better than leaving this area blank! The JIRAM data appears a bit different from the JunoCam data in the mosaic but this is mainly because the JIRAM images suggest that the overall color and brightness in the area very near the pole (including the central cyclone) really are different from areas farther from the pole. Another factor is that the JIRAM data is of somewhat higher resolution. Also unlike JunoCam, the difficult illumination conditions in the polar region do not affect the JIRAM images. And here is the montage:



The montage shows the following:

Upper left: An approximately true color/contrast mosaic of Jupiter's north polar region.
Upper right: A mosaic of Jupiter's north polar region with enhanced colors and contrast.
Lower left: The approximately true color/contrast version with a latitude/longitude grid. Latitudes are planetographic.
Lower right: A diagram showing the areas covered by the different source images/data. Unless otherwise noted the data is from JunoCam.

[Gerald]

Recently, John Rogers showed, that the north polar region is illuminated well enough now, that it's possible to derive multi-perijove composites including the north polar cyclone, see missionjuno Think Tank, Philosophia-47 2020-08-16 23:04 UT.
The version below tries to stay fairly seemless, but accepts some overlap of features, especially of some FFRs. It's composed of stacked maps derived from PJs 25, 26, 27, and 28, similar to John's version.

But the long-lived structures are shown unambiguously: The north polar cyclone (NPC), the eight northern circumpolar cyclones (CPCs), and the two anticyloncic white ovales (AWOs) inside the CPC octagon. The latter appear to distort the ditetragonal shape of the octagon into a slightly rhombic geometry by their opposite or "para" position relative to the NPC.
The map is equidistant azimuthal planetocentric from 75 to 90 degrees north.