JUNOCAM GLOBAL MAPS
JUNOCAM CYLINDRICAL MAPS
This page presents the global cylindrical maps of Jupiter produced at each perijove from the JunoCam images.
The links are at the foot of the page.
For sets of north and south polar maps, please go to the page ‘Results from Juno: Jupiter’s polar regions’: Results from Juno: Jupiter’s polar regions – British Astronomical Association
(1) CYLINDRICAL MAPS, PJ1-PJ48
They are composite RGB maps in equirectangular projection using planetocentric latitudes, usually at 10 pixels/degree and with L3=0 at the centre. Latitude and longitude (L3) scales have been added to most maps. Formats were variable at the early perijoves.
The raw images were processed and map-projected by Gerald Eichstädt, then the single-image maps were composited by John Rogers in Adobe Photoshop, except for some of the later perijoves when G.E. experimented with an automatic assembly technique. There are two exceptions (PJ22 & PJ29) when we present maps by Brian Swift instead, having been posted on the JunoCam web site.
At the first few perijoves the close-up images were not included in the maps, and the longitude orientation was approximate (± 1-2°), as we deduced it by alignment with ground-based observations before accurate navigation was established. There are still small uncertainties in navigation so positions may be uncertain by a few pixels. Intensities and colour balance are arbitrary, and have been adjusted to reduce visible seams between images and to enhance regional contrast. Therefore, any broad diffuse features should not be relied on without consulting the original single-image maps. Adjustment of colour balance was especially necessary in 2021-22 as the original images became progressively redder, apparently due to radiation-induced reddening of the camera optics. Recently, G.E. has applied a correction for this. Nevertheless, there are still noticeable differences in intensities and colour balance between different maps.
The global coverage has varied during six years of the mission due to the evolution of Juno’s orbit. At the early and the most recent perijoves, when the sub-spacecraft track was not far from the terminator, Juno was usually oriented so that JunoCam obtained extensive inbound coverage of the northern hemisphere and outbound coverage of the southern hemisphere. In the intervening years, pointing constraints meant that less of the northern hemisphere was imaged. There were no images at PJ2, and none of the northern hemisphere at PJ19 and PJ48.
The maps are in JPEG format in the ZIP files linked below. (TIF files are available if needed.) For some perijoves, an additional, labelled copy of the map is included, as posted in JHR’s perijove reports. These can be found on this web site and on the JunoCam web site (https://www.missionjuno.swri.edu/junocam/think-tank).
The maps are provided under a CC-BY licence: “The CC BY licence allows anyone to: copy, distribute and transmit work; adapt work; make commercial use of the work under the condition that the user must attribute the work in the manner specified by the author or licensor (but not in any way that suggests they endorse the user or their use of the work).” I.e. these maps are in the public domain but should always be credited as indicated (NASA / JPL / SwRI / MSSS / Gerald Eichstädt / John Rogers); and we ask that anyone wishing to use them for research or commercial purposes would contact us first.
–John Rogers (2023 Feb.16).
(2) CYLINDRICAL MAPS, PJ49-PJ72
The notes above all apply to this second batch of maps, except as follows.
Most of the cylindrical maps in this batch were assembled by Gerald Eichstädt using a semi-automated procedure, sometimes followed by adjustments by JHR to reduce artefactual disparities in brightness and colour. Hence, the colour balance is arbitrary. Gerald also produced methane-band (CH4) maps for all images, only some of which have been assembled and included here.
The coverage and resolution of the images has progressively changed due to Juno’s orbital evolution: while the orbit remains highly elliptical and near-polar, the point of perijove has steadily moved northwards and has shifted from the day side to the night side. After PJ50, Juno’s close approach track was on the dark side of Jupiter, so there was no v-hi-res imaging of cloud features, and the maps are composites of inbound and outbound imagery. Up to PJ60, inbound images covered most of the planet — sometimes over two successive rotations, so some regions could be mapped twice and ‘blinked’ to show the currents, though only the last inbound rotation gave high resolution. The inbound trajectory did not give good views of the high southern latitudes, which were supplied from a subsequent outbound rotation. (Gerald’s separate maps for each rotation are available if needed.) From PJ62 onwards, inbound coverage was reduced to only one sector of the northern hemisphere, and outbound coverage was still restricted to >~18°S. There were no images at PJ71.
–John Rogers (2025 July 14)
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Links to ZIP files of the maps:
Second batch:
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