Europa Flyby - PJ45, September 29, 2022 Options

[Decepticon]

Juno is set to flyby of Europa on Sept. 29, 2022 (PJ45)

I can't wait to see the results of this flyby!


Sadly not much information is available online.


Jason Has a beautiful animation of encounter on youtube.

https://www.youtube.com/watch?v=r9bx1GcoqEE...nel=volcanopele

[mcaplinger]

Junocam will take four RGB images on one-minute intervals starting at around terminator crossing (roughly 09:37:30 UT), using the same method used for the Ganymede imaging last year. I'm not sure when we can expect the data to show up, hopefully before that weekend but no guarantees.

[volcanopele]

Thanks for that bit of info! In the morning I’ll make a set of preview images. I made one that I posted on Twitter but I think that was for the opportunity after the one you mentioned.

[StargazeInWonder]

It seems, from the blurry quality of the base map in the upper right of the preview image, that there's reason to expect that this image may be an upgrade on the best coverage we have of that part of Europa. That would be great.

[mcaplinger]

It seems, from the blurry quality of the base map in the upper right of the preview image, that there's reason to expect that this image may be an upgrade on the best coverage we have of that part of Europa.

Probably. USGS coverage maps claim 6 km/pix over that area and we should get 2-4 km/pix. But we've found that the coverage maps are often optimistic about resolution, as some of it is motion-blurred or otherwise not great. On the other hand, it's a fast flyby and I don't want to overpromise anything.

[vjkane]

Probably. USGS coverage maps claim 6 m/pix over that area and we should get 2-4 km/pix. But we've found that the coverage maps are often optimistic about resolution, as some of it is motion-blurred or otherwise not great. On the other hand, it's a fast flyby and I don't want to overpromise anything.

6 m/pix is several order of magnitude better than 2-4 cm/pix. Is the first number or scale misstated?

[mcaplinger]

6 m/pix is several order of magnitude better than 2-4 cm/pix. Is the first number or scale misstated?

Sorry, yes, obviously, I meant km/pix. Edited.

[vjkane]

Sorry, yes, obviously, I meant km/pix. Edited.

Do that all the time myself.

Looking forward to this flyby. Will be especially interested in what the microwave radiometer finds about the ice shell structure, but expect that will have to await publication of a peer-reviewed paper unlike the raw images.

Out of curiousity, I presume that the microwave radiometer is a passive instrument - is this correct?

[mcaplinger]

Out of curiousity, I presume that the microwave radiometer is a passive instrument - is this correct?

Correct. Strictly speaking, there's no such thing as an active radiometer. Anything that has active and radiometer in the name is probably some kind of hybrid radar/radiometer, but MWR is not that, it's receive-only.

https://dataverse.jpl.nasa.gov/file.xhtml?f...amp;version=1.0 is sort of old, but the full Springer paper is paywalled, alas.

[StargazeInWonder]

Some write-ups of Juno's microwave radiometer observations of Ganymede have recently been published, about a year after the flyby, and should give a rough idea of what capabilities it has regarding Europa.

https://meetingorganizer.copernicus.org/EGU...GU22-10748.html

[volcanopele]

I'm not sure when we can expect the data to show up, hopefully before that weekend but no guarantees.

One thing to keep in mind for everyone is that Artemis is playing havoc on the DSN schedule for a lot of missions. The first launch opportunity is on the 27th and if that is a go and succeeds, there be might some impact on the schedule for later that week. So if images show up later than everyone expects compared to previous perijoves, that could be why.

[StargazeInWonder]

DART will reach its destination on September 26. It's going to be a big week.

[volcanopele]

Going with Mike's first image time, here are preview versions of each JunoCAM image:

[vjkane]

Correct. Strictly speaking, there's no such thing as an active radiometer. Anything that has active and radiometer in the name is probably some kind of hybrid radar/radiometer, but MWR is not that, it's receive-only.

Thanks. The depths of measurements in Europa's ice shell from a presentation about a year ago made me wonder if the instrument did have an additional active mode.

[mcaplinger]

Going with Mike's first image time, here are preview versions of each JunoCAM image...

Nice, but my sims show Europa not leaving the FOV so quickly. Are you using a C kernel like juno_sc_prl_220928_221105_jm0450a_v01? There's a 4.5 degree offset from grav orientation for this pass.