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Posted by: TrappistPlanets Apr 19 2021, 11:14 AM

After some tinkering with 2 images of Janus, I have re-projected and worked on a accurate map for the moon.
The only other surface map i know of is http://www.johnstonsarchive.net/spaceart/cmaps/janusmap.jpg , but its super low resolution.





there was a another image of Janus i wanted to compile in there but i couldn't seem to find the view in relation to a 3d model so i can find the pole of the moon for re-projection


and it does line up correctly to the model in Celestia




hope you enjoy this new map
(there may still be some minor alignment issues)

Posted by: JRehling Apr 19 2021, 03:20 PM

Fun! And thanks for that. How appropriate that your map covers two faces of Janus.

It seems like these images cover part of what is in your map:

https://photojournal.jpl.nasa.gov/catalog/PIA18369

https://photojournal.jpl.nasa.gov/catalog/PIA18299

It seems like this offers a bit of coverage that is best of its kind for this part of Janus:

https://photojournal.jpl.nasa.gov/catalog/PIA14607

And this image seems like it might bridge much of the uncovered territory in the middle of your map:

https://photojournal.jpl.nasa.gov/catalog/PIA12714

Another useful one?

https://photojournal.jpl.nasa.gov/catalog/PIA12602

And the south:

https://photojournal.jpl.nasa.gov/catalog/PIA11597

I had not kept track of the status of Janus imagery before. Thanks for giving this world its due!

Posted by: volcanopele Apr 19 2021, 04:16 PM

Unfortunately, Janus was poorly covered by Cassini, when compared to the excellent coverage of its partner Epimetheus. Beyond the images released in the Photojournal, a quick search of OPUS reveals a few more opportunities that could be added to the map:

https://opus.pds-rings.seti.org/opus/#/instrument=Cassini+ISS&mission=Cassini&target=Janus&cols=opusid,instrument,planet,target,time1,observationduration&widgets=instrument,mission,planet,target&order=time1,opusid&view=browse&browse=gallery&cart_browse=gallery&startobs=1431&cart_startobs=1&detail=

Unfortunately a lot of the better quality images were taken at higher-phase angles, but maybe there are a few that can expand coverage.

Thanks TrappistPlanets for giving this a try. Would be good to see more Cassini-based shape models and maps of the minor moons become available.

Posted by: kymani76 Apr 19 2021, 05:41 PM

Thanks for the map, it's really nice. I will attempt to improve the coverage when I find some time.
Here is the map aligned with 3d model of Janus:

Posted by: TrappistPlanets Apr 19 2021, 06:42 PM

JRehling, all links are broken, can you post them as pic attachments please

Posted by: Tom Tamlyn Apr 19 2021, 06:58 PM

The links work for me ....

Posted by: TrappistPlanets Apr 19 2021, 10:53 PM

i already have this one ( https://photojournal.jpl.nasa.gov/catalog/PIA12602 ) in my map (its the blurry territory in my map)
the only other important thing i can get from that is the face of Epimetheus that is in there



and them links work on my chromebook but not my PC... weird (don't reply to this part to stay on topic)

Posted by: TrappistPlanets Apr 19 2021, 11:00 PM

as for https://photojournal.jpl.nasa.gov/catalog/PIA11597 it says where the pole is (in numbers) but idk where it is to be exact in relation to the numbers its giving me, can someone help

Posted by: TrappistPlanets Apr 19 2021, 11:07 PM

QUOTE (volcanopele @ Apr 19 2021, 05:16 PM)