It is easy to forget that JunoCam isn't the only instrument aboard Juno that can obtain images. The Jovian Infrared Auroral Mapper (JIRAM) instrument can obtain images in two infrared bands. One of these, centered at a wavelength of 4.78 µm, shows thermal radiation emitted from Jupiter. This radiation is caused by heat from Jupiter's warm interior - as a result there is no difference between the dayside and nightside in these images. Therefore they are great for looking at Jupiter's north pole which isn't visible in the JunoCam images because it is currently winter in Jupiter's northern hemisphere.
Here is a tweened time-lapse created from three JIRAM image mosaics obtained over an interval of slightly less than three hours shortly before perijove 4 on February 2, 2017:
jup_jiram_npole_anim_20170202.mp4 ( 2.11MB )
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Because Juno was approaching Jupiter the image sharpness increases from start to finish.
In case you are unable to play the MP4 file above the time-lapse can also be viewed at Vimeo (the quality is somewhat lower though): https://vimeo.com/263221959
All of the JIRAM images through perijove 6 are available at the Planetary Data System Atmospheres Node and can be converted to PNG files using IMG2PNG. Thousands of images have been obtained by JIRAM.
Usually a spacecraft's highest resolution imaging instrument is a visible light camera but Juno is an exception. JIRAM's resolution is higher than JunoCam's. While JIRAM's images are small compared to the JunoCam images (only 432 pixels in the horizontal direction) it has much narrower field of view than JunoCam (5.9 degrees vs. JunoCam's 58 degrees). Combined, this means that the JIRAM images have about three times higher resolution than the JunoCam images but they also cover a much smaller area.
Here is a mosaic of Jupiter's north polar region from the data that was used to create the animation above:
http://junocam.pictures/gerald/uploads/20180326/, converted to 8-bit PNG, and various synopses as tiles of 10 columns.
However, depending on what you are doing it may be important to use 16 bit PNGs (especially if you want to reveal details in very dark areas).
Here is a third animated GIF from JIRAM images. The source images were obtained during the perijove 5 pass on March 27, 2017. The animation consists of 104 frames that cover a period of one hour. Unlike the other two animations which had a frame rate of 30 frames/second the frame rate here is 25 frames/second (30 was too fast). At the start of the animation Juno's distance from Jupiter's center is 167000 km but at the end it has increased to 254000 km.
A side-by-side IR and visible comparison could be quite revealing in helping to make sense of the clouds, with their varying altitudes and opacity in visible light. There is https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA22336 from JPL that shows one way to process a JIRAM image. Depending on JIRAM's resolution, combining IR and visible data can help with deriving 3D cloud fields that could then be rendered from varying perspectives in visible light.
A couple of weeks ago, I stitched some of the JIRAM images, simply using Hugin. But they are flipped. I noticed this too late before PJ12, and after Alberto Adriani's hint:
This is a composite of multiple frames of Io, englarged, registered and merged. There were two sequences of slightly different image scale, but pretty much the same geometry.
I must say I wasn't expecting images that good of Io.
Phil
JIRAM image of the south polar pentagon on Perijove 6 (May 19)
JIRAM mosaic of some of the north polar cyclones
Interesting visible and IR comparisons. Generally the whiter JunoCam clouds are darker in IR and thus colder and higher. Assuming all the clouds are equally opaque, one could make a 3-D version of the JunoCam images with whiter clouds (really the clouds darker in IR) being just slightly elevated in altitude.
I played around with Gerald's JIRAM dataset - please enjoy and share this video featuring music by the sublime Max Richter:
https://vimeo.com/446494003
I finally found time to convert JIRAM IMG files of orbits 09 to 26 into PNG, and updated http://junocam.pictures/gerald/uploads/20180326/.
Thus far, I've only provided zipped PNGs, no large synopses, yet.
Some of the JIRAM image products consist of two framelets, (presumably) of a 4.5 to 5.0 µm region in the upper half and a 3.3 to 3.6 µm region in the lower half. In those cases, the products I'm providing suffer from the significantly different signal levels making the ~3.3 µm region almost black, if there is a signal in the ~5 µm region. I might find time to fix that issue at some point in the future, but probably not too soon. The 3.3 µm primarily shows aurorae. I think that it's an emission line of the https://en.wikipedia.org/wiki/Trihydrogen_cation H3+, IIRC.
I even didn't find enough time yet to take a thorough look at the majority of this large number of images. But what I've seen is beautiful, including images of Io with more than 30 hot spots. Enjoy! There is a lot to discover.
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