Juno is in a 53-day orbit. When it passes close to Jupiter (“PeriJove”
or “PJ”) we will take as many pictures as we can. The number of pictures that we take is
limited by the amount of onboard data storage that we have for JunoCam, so we
have to be selective. The images are
collected as we go from the north pole of Jupiter to the south pole, which
happens in a brief 2 hour portion of the orbit.
On any given perijove pass we will only be able to image targets in a
narrow swath of territory the spacecraft flies over (“groundtrack”).
Juno’s orbit geometry is evolving so we will carry out
campaigns rather than voting on specific targets. Campaigns are focused on a specific science
theme and take advantage of the changes in lighting.
What happened to Voting?
Up through PJ8 everyone could vote on their favorite Point
of Interest (POI) and those rounds can be viewed here. Changes in the orbit and mission plan mean
that we are no longer selecting targets by vote.
There will still be a voting page for every orbit and we
will describe the specifics of each perijove pass such as the spacecraft
orientation. Because of the challenges
to predict the Points of Interest that will be in the JunoCam field of view we
are now timing the image collection by latitude and/or executing campaigns.
We will take polar images on every PJ pass to assemble
timelapse sequences to study the dynamics of the circumpolar cyclones. Between the north and south pole images will
be timed to get complete latitudinal coverage.
The rest of the resources will be used for campaigns. Options are to look for lightning, take
multiple methane images to study high altitude hazes, study Jupiter’s ring,
take stereo pairs for cloud altitudes, image Galilean moons when available, etc. We will keep the Voting Round discussion for
comments on what would be best. We are
hoping that you enjoy being a part of this process, that you enjoy being a member
of the JunoCam team.
Voting Round :
CLOSED : 2018-04-01 00:00:00
Perijove on : 2018-04-01 09:47 UT
About This Round
As Juno's orbit evolves we are spending more time on the night side of Jupiter, and perijove is moving closer to the subsolar point. The orbit is also rotating such that the closest approach point is moving northward. In order to take advantage of good lighting while we can the project agreed to re-orient the Juno spacecraft for this pass. We will not be voting this pass - go to winner selection to read how the images will be taken.
We will start inbound imaging 19 hours before the closest approach. These distant images are at a high phase angle but will give us context for later images.
About 2 hours from closest approach we will image Io. We are planning to take two pictures - one exposed nominally and one that over-exposes Io to look for volcanic plumes extending above the surface.
For the 2 hours between our best view looking down at the north pole and looking up at the south pole JunoCam will carry out several campaigns.
Timelapse sequences of images of the north pole and the south pole will allow us to generate movies showing the motions of the circumpolar cyclones.
The Great Red Spot (GRS) is close to Juno's ground track. We will image the region just east of the GRS when we are close. As the spacecraft recedes from Jupiter and our field of view covers more territory we will capture the Great Red Spot in its entirety.
Towards the end of the perijove pass we will image Ganymede. Update: We missed Ganymede, but Io is in this image.