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Posted by: volcanopele May 10 2023, 10:11 PM

Perijove 51 is next Tuesday (Monday evening here in Tucson). I've published a new video about the Io encounter during this pass along with a review of the JunoCAM images from the last one back on March 1:

https://youtu.be/6oMDd7rAeHw

The biggest takeaway is that this is a VERY long encounter. Just as an example, during PJ49, Io was only covered at least in part by the JIRAM field of view for 6 minutes. During PJ51 it will be in the JIRAM field of view of more than 7 glorious hours. Io will also be in the JunoCAM field of view for more than 48 hours, though obviously Io will be too small for most of that time, but still! Definitely looking forward to this encounter next week. I'm on travel during the encounter, but I'll be back home the time any JunoCAM data arrives (I presume that because we're only a month post conjunction that we can expect a bit of a delay, but that's perfectly fine).

Posted by: john_s May 11 2023, 01:24 AM

Great video! Looking forward to the data.

John

Posted by: mcaplinger May 11 2023, 01:35 AM

Nice video, Jason. Sorry to disappoint, but Junocam is only taking 10 images of Io this time, from about 02:30 to 03:45. They are all lossless.

Posted by: volcanopele May 11 2023, 06:34 AM

I suspect that Prometheus will be a bit too far from the terminator in the first image, but one can always hope. But Io should be in some of the Jupiter images…

Posted by: StargazeInWonder May 18 2023, 12:12 AM

Raw images are up on missionjuno.

Maybe a plume in JNCE_2023136_51C00069_V01-raw? Not many pixels, but it seems like it could be one.

Posted by: volcanopele May 18 2023, 12:38 AM

Might be the mountains around Gauwa Patera.

Posted by: volcanopele May 18 2023, 01:12 AM

There MAY be a plume in JNCE_2023136_51C00065_V01. I'll need to check the location...

No, I'm not so sure about it... too far west to be Prometheus....

Posted by: volcanopele May 18 2023, 01:54 AM

One image down, eight more to go.

Finally some absolute, no doubt about it surface changes around Volund. The northwestern distal flows are much darker and there is a new patch of dark material on the west side of Volund. This matches what we've seen with JIRAM in the last few flybys.

Posted by: J.J. May 18 2023, 05:21 AM

There are some spots visible in the dark side of the image on the left; are these glowing lava flows, or hot pixels?

Posted by: StargazeInWonder May 18 2023, 05:34 AM

The raw images have many pixels. However, as pretty much all of the terrain was imaged >2 times, it should be possible to rule out which if any correspond to anything physically real.

Posted by: volcanopele May 18 2023, 05:51 AM

Strip of three images (63, 64, and 66). Sorry for the terse description. It’s getting late here… and I really could use some sleep…

I will make a quick note that if you see any random green spots, that’s noise. Red spots, now those are things I need to check, but in the morning.

Posted by: Kevin Gill May 18 2023, 03:54 PM

Yeah, there does appear to be something going on just east/right of the terminator in JNCE_2023136_51C00069_V01. Bright spot appeared in all three color channels reducing the likelyhood that it's the result of a hot pixel or particle hit.

Posted by: volcanopele May 18 2023, 04:29 PM

yeah, that's definitely one of the mountains around Gauwa Patera at 40N, 5W.

Posted by: Kevin Gill May 18 2023, 06:19 PM

That then makes me wonder if it's simply that a peak is poking up into the sunlight from beyond the day/night terminator.

Posted by: volcanopele May 18 2023, 11:04 PM

Okay, I'm a bit more convinced that the plume in image #65 (the over exposed one) is real. It shows up in two filters. There are no known mountains. It's too tall to be a mountain. The limb location of 11S, 165W is consistent with Culann, an occasional plume site from Galileo.

Posted by: Bjorn Jonsson May 18 2023, 11:08 PM

That's what's happening. There are some nice examples of this in the Galileo images, for example these:

https://photojournal.jpl.nasa.gov/catalog/PIA00738
https://photojournal.jpl.nasa.gov/catalog/PIA01107
https://photojournal.jpl.nasa.gov/catalog/PIA01103

Posted by: volcanopele May 18 2023, 11:45 PM

Here is the full set of 8 images. Pele is still there as a plume deposit. It keeps being on the limb so it's hard to say if it is fading or if it is just the difference in filters. Still the most prominent surface changes are at Volund, East Girru, and Chors Patera. The triangular patch mentioned in the caption for the images released last week is now seems to be mountains that are surrounded by a "moat" of SO2 frost. Or at least a pair of mountains. Not entirely sure about the northeastern of the three patches.

Posted by: john_s May 19 2023, 02:03 PM

Great pictures- thanks, Jason. Those frost halos around mountains seem to be a feature of Io's poles- Voyager 1 saw the same thing at Haemus Mons near the south pole. I still don't think there's a good explanation for them.

John

Posted by: Antdoghalo May 19 2023, 05:14 PM

The frost halos seem to be all over Io. What is polar specific are the plains covered in scarlet material which make the tan frost halos more prominent there. A possible mechanism may be landslides of lighter material on the mountains depositing it around them.

Posted by: Decepticon May 22 2023, 11:10 PM

https://www.space.com/nasa-juno-jupiter-io-volcanic-moon-images

Posted by: Bjorn Jonsson May 24 2023, 12:32 AM

An 8 image montage together with computer generated images with a latitude/longitude grid. The computer generated images are based on a Voyager/Galileo map of Io. Mountains (or hints of mountains) are visible near the terminator in some of the images, for example in images 62, 63 and 69.

Posted by: Brian Swift Jun 3 2023, 04:28 AM

My take on Io images. North up. Natural-ish and exaggerated color/contrast.

Full Rez PNG at https://www.missionjuno.swri.edu/junocam/processing?id=15180

Posted by: Candy Hansen Aug 25 2023, 07:08 PM

We have posted PDS formatted images of PJ51 Io on the missionjuno Think Tank page. Scroll to the bottom of the Tools of the Trade tab.
Note that these images are only intended for expert ISIS users that know how to navigate around spice kernels. Use only reconstructed kernels.

Posted by: volcanopele Aug 25 2023, 08:10 PM

ooo, and these include the RDRs. Thanks, Candy! I'll take a look at these over the weekend. I suspect that my old control point network won't work due to differences in serial numbers in ISIS but I do want to see if photomet applies more accurately with these RDRs.

Posted by: volcanopele Feb 14 2024, 04:55 PM

JIRAM M-band composites from two of the sequences. JIRAM stared at Io for several hours during PJ51 so the difference in geometry makes it hard to make a single composite so I'm processing these one sequence at a time. I'm also only going to bother with the 2 ms data, not the 4 ms stuff. Yes, the 4 ms data has better SNR but I can avoid much of the smear with the 2 ms stuff and I have to constrain what I'm working on somehow. Any mismatches you see are due to the fact that I started using my crude (but reasonably well controlled) Io control network with this data set and the background map is still the USGS basemap.

I see past me's comment about serial numbers and this will likely lead me to edit the RDR labels during ingestion on my end so that I can still use my control point network on them because there is NO WAY I am redo'ing all this work...