Juno Perijove 57, December 30, 2023 Options

[volcanopele]

I know the first close Io flyby is still a couple of months away but I'm going to go ahead and start up the topic now with a few preview images that the global map from PJ55 into the pixel scale, lighting conditions, and orientation of the highest resolution images that JunoCam would take (illuminated by the sun, there's always a chance for Jupiter-shine images), based on the current reference spk and c-kernel:




This also assumes an image cadence of 1 every other rotation (so 1 per minute).

info about the encounter:

CODE

Perijove    Date (UTC)    SC Altitude (Io, km)    SC Latitude (Io IAU, deg)    SC W Longitude (Io IAU, deg)    Vinf (Io, km/s)    Phase Angle    Magnetic Latitude of Io (Jupiter System III, deg)    E Longitude of Io (Jupiter System III, deg)    True Anomaly of Io (deg)    Separation Angle
PJ57    12/30/2023 08:36:00.681    1500.021    63.694    94.641    30.047    108.885    3.418    228.269    248.805    21.175

[volcanopele]

Edited to include the first six instead of the first and third (skipped one) using the global map I generated from PJ55 images.

[Antdoghalo]

Will this flyby get an entry on the Gish Bar Times?

[volcanopele]

at this point, probably not (grumble grumble prior publication). That being said, I've considered doing a follow-up video for Youtube and might do some live events for the flyby and stream my processing work.

[Decepticon]

Very excited to see any changes at Loki.

[Tom Tamlyn]

I know the first close Io flyby is still a couple of months away ....

Juno is going even closer?

[Explorer1]

Juno is going even closer?

Yes, December 30th and February 3rd, only 1500 km!

[StargazeInWonder]

The next two flybys will be close enough that Doppler radio science is expected/hoped to provide meaningful science regarding Io's interior. The Galileo Orbiter made several flybys even closer than this; I am unsure what, if any, benefits may be obtained as a result of superior technology or differences between the geometry of these flybys and those made by Galileo.

The combination of PJ55 and the next three close Io flybys will provide something approaching global coverage at about the resolution of PJ55 or better. So all told, it's going to be a pretty nice dataset given that the surface of this world changes over time and the last detailed imagery of many areas is ~20-25 years old.

[john_s]

I've heard that the Juno gravity data will have higher precision than the Galileo data, so a couple of close Juno flybys will provide a considerable improvement in understanding Io's gravity, beyond the half-dozen flybys that Galileo accomplished.

John

[mcaplinger]

We're less than a week out from the Io flyby. The first Junocam image should be taken at 2023-364T08:37:21 +/- 15s and the first four images are at 60s spacing.

[volcanopele]

Preview images using the latest ephemeris and c-kernel. First image according to that kernel has the green frame centered on Io at 2023-Dec-30 08:37:07.177. Preview images are spaced every 2 rotations.




I take it that there are not images prior to C/A/ Looked like there might be some decent imaging at ~19 km/pixel of the anti-Jovian hemisphere. A bit disappointed at the lack of Jupiter-shine images but given what happened in PJ56 I totally understand.

[mcaplinger]

I take it that there are not images prior to C/A

Correct. Maybe we should have taken one, but Io starts leaving the FOV illuminated limb first by the time the resolution has gotten decent, so we judged it wasn't worth it.

[Antdoghalo]

Would have been cool to test if there was airglow from the volcanoes. Will the SRU be taking pictures of the night side?

[volcanopele]

They can take one. I'm hoping they can get one showing Tonatiuh, a large lava flow (~500 km long) north of Zal that formed between 2008 and 2018 (between first ground based detection of a hotspot to a 150-km shifting of the flow front in 2018). Kinda difficult given the longitude (~65-85°W) but even something just showing the general morphology of the flow would be useful enough. For example, I'm pretty sure that the eastern end is the source based on ground-based data, but there are no visible edifices at that end in older imagery. There is one toward the western end in Galileo imagery, and maybe the "western expansion" in 2018 was just a fresh, westward flow from that source.

[volcanopele]

having a bit too much fun prepping for a preview video...