Juno Perijove 49, March 1, 2023 |
Juno Perijove 49, March 1, 2023 |
Feb 14 2023, 09:35 PM
Post
#1
|
|
Senior Member Group: Moderator Posts: 3233 Joined: 11-February 04 From: Tucson, AZ Member No.: 23 |
I'm going to choose to be optimistic about PJ49, so with that in mind, I have added previews of JunoCAM's observations of Io for PJ49. Obviously, JunoCAM's real observation plan will likely differ but I added previews for the first and last opportunities to image Io on the pass, a preview of an image nearest closest approach, and one for when Io is near the center of the JIRAM FOV. The observation at closest approach also has the Marduk plume which has a good chance of being observed on this encounter, presuming it is active. The Volund plume might also be visible near the terminator.
The previews use the Voyager/Galileo basemap. The left images were originally projected at the same resolution as JunoCAM but were then enlarged by 5x while the image on the right is the basemap reprojected to 5x the JunoCAM pixel scale. https://pirlwww.lpl.arizona.edu/~perry/Juno/pj49.htm -------------------- &@^^!% Jim! I'm a geologist, not a physicist!
The Gish Bar Times - A Blog all about Jupiter's Moon Io |
|
|
Mar 13 2023, 11:39 PM
Post
#2
|
||
Senior Member Group: Moderator Posts: 3233 Joined: 11-February 04 From: Tucson, AZ Member No.: 23 |
Uploading a new version that deals with the artifact in JNCE_2023060_49C00076_V01 much more elegantly. There is a large splotch in the flat field for the red filter at sample 1194, line 43 that I've always had a hell of a time removing. The splotch seems to be in a different spot compared to its position in PJ34-PJ35. I created a new flat for red using Jupiter images from PJ49 and that cleaned it right up so Susanoo and Mulungu no longer look red. To create my flat, I utilized images of Jupiter from PJ49 where Jupiter fills the field of view for at least some of the frames, so for example JNCE_2023060_49C00105_V01 and JNCE_2023060_49C00104_V01. I used cubeit and cubeavg to create a single image that is the average of all of 44 frames. I need to remove the gradient caused by illumination conditions on Jupiter. So first I take a copy of that average image and I null out all the splotches seen. I then shrink the image to a full-width, single line then expand it back out to full size. This creates an image with just the gradient. Then I ratioed the average image with this gradient image. This has the effect of removing the gradient and normalizing the image. Not the best flat for large-scale gradients in the detector since I'm effectively filtering them out, but does a good job in dealing with the splotches. -------------------- &@^^!% Jim! I'm a geologist, not a physicist!
The Gish Bar Times - A Blog all about Jupiter's Moon Io |
|
|
||
Lo-Fi Version | Time is now: 24th May 2024 - 03:14 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |