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 : 2019-05-30 00:00:00
Perijove on : 2019-05-29 09:24 UT
About This Round
The tail petal of Juno's elliptical orbit is moving into the midnight sector, which means that at apojove the spacecraft is on the night side of Jupiter. At perijove the spacecraft groundtrack is closer to the subsolar point than in previous passes. When gravity science is the primary goal (most passes) the solar arrays remain pointed at the sun throughout the perijove pass. For PJ20 however we have chosen to re-orient the spacecraft such that the view for the remote sensing instruments is closer to the groundtrack.
Jupiter is not in JunoCam's field of view until just 3 hours before closest approach, and when it comes into view we are looking at the dark side, so we begin with a lightning search. At 40 min before perijove we will start taking images of the north polar region. Because the off-sun orientation is good for images throughout the perijove pass we focus our resources on tight latitudinal spacing and include a campaign to study mesoscale waves in the equatorial zone. Outbound, after passing over the south pole, Juno is departing on the nightside so we will execute our first southern hemisphere lightning search.