Io flyby coming up in a couple of hours. C/A distance is 22,241 km. Will cover the same region that we've seen of late, the northern trailing hemisphere. Might see the Prometheus plume just pass the terminator in the early images.

Ground track map for this flyby and later encounters:

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That's excellent how the four general track locations cover different terrain. I'm sure that the resolution is not near the par of any planned dedication Io mission, but this is still a pretty solid Io mission in its own right. And the radio science and magnetometer data is also potentially excellent. This shapes up as one of the most exciting opportunistic mission extensions there's been. Just make it through 7 more orbits, Juno!

All images have been pushed to missionjuno. Enjoy.

Thanks! Here's an initial quick look at JNCE_2023212_53C00121_V01


Io - PJ53-121

The plume you've all noticed near the terminator is Prometheus...

The one almost exactly at the 6 o'clock position, a bit far from the sun-lit portions, visible if you crank the brightness way up?

PJ53_114
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For the curious, currently working on a control network. Seems to need one big one for as many images I can add within reason...

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First image and map complete. Other images in preparation.

Data dump time!

Click to view attachmentNot sure if this attachment will work, but this is an mp4 animation of 12 of the Io images.

Click to view attachment Same 12 images in an image strip.

Click to view attachment Took that previous montage and cranked up the brightness to 11 to highlight the Prometheus plume on the nightside.

Gerald (or anyone) what did you get for start time offset on PJ53_165? I got 0.2463 second.

Also, Gerald I concur that PJ53_165 is showing an occultation of Io by Jupiter.
The following 5x enlarged image shows markings on limbs on raw data of blue filter for which occultation is most progressed.
Will be interesting to see where Jupiter limb moves after we get reconstructed SPK.
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There was a new CK delivery late in the week. Not sure if that would help with limb fitting for you. I'm using ISIS's jigsaw for correcting Io's position and orientation so the exact file I use doesn't really matter...

Thanks for posting these great images - I particularly enjoyed the animation sequence. I have a couple of questions about the Prometheus plume. Is it visible here because the top of it rises up into sunlight or for some other reason? Does it erupt continuously or was this sighting just a lucky chance?

Thanks. With the V02 CK file, time offset (from visual limb fit to Io) is only -0.01246 sec.

Scaled 5x raw data with limb markings:
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Image sequence of Io not-occulted PJ53_164, Io partially occulted by Jupiter PJ53_165, difference _165 - _164
Images scaled up ~14x.
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And a 2nd version with markings where Jupiter's 1-bar limb should be and final image is Abs difference of _165 - _164.
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PJ53 Image Collection. Exaggerated color/contrast.
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Full resolution version at https://www.missionjuno.swri.edu/junocam/processing?id=15460

A montage of 15 images of Io, i.e. images 113 to 127. The images are enlarged by a factor of 3 relative to the original data. North is up in all of the images.

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Computer generated images with a latitude/longitude grid are also included. They are based on a Voyager/Galileo map of Io.

PJ53 Io EQR Map Exaggerated Color/Contrast 8ppd jpg
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16ppd PNG at https://www.missionjuno.swri.edu/junocam/processing?id=15556
16ppd natural-ish color/contrast png at https://www.missionjuno.swri.edu/junocam/processing?id=15555

Interesting those features in the upper left portion of Brian's map seem to show mountain shadows when compared to the white features in a prior map (section shown below). A new one can be seen in the upper left corner of Brian's map very close to the pole.

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Here is a flip view between my map and the corresponding area of the USGS Io map.
(Note, I didn't attempt to align my map with the USGS map.)
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Jason already noticed the change in the Volund area in PJ51. https://www.jpl.nasa.gov/images/pia25964-io-over-the-years

Nice to see the blinking animation. The associated feature name I've seen is Vivasvant Patera as per this map. I've yet to see any "Montes" type feature names in this area. The names in the map are distorted on the cylindrical projection so that they look good when projected on a sphere.

As far as names go, stay tuned (particularly the ones in the triangle shaped bright area west of Dazhbog).

Yes, there are several mountains in the north polar region. some were previously known, but the new data does give us a better idea on the shape. Since PJ55 is basically a carbon copy of PJ53 but closer we should get a better handle of the shapes of these mountains this weekend. What we don't have a good handle on are the paterae, not a surprise given they're shallower than the mountains are tall so shadows are harder to spot (though not impossible, as Michabo and Thomagata were visible near the limb on PJ53).

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My apologies. I got distracted by the changing feature on the right, just below center of the flip view crop, and forgot you were interested in the mountains in the upper left.

I can see that both of these corners are pretty interesting to check out!

PJ55 will definitely be a closer up of PJ53 so seeing these changed areas in further detail will be intriguing.

JIRAM M- and L-band composites from PJ53:

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