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 : 2018-02-07 00:00:00
Perijove on : 2018-02-07 13:53 UT
About This Round
This perijove pass will be carried out in the gravity orientation which points the solar arrays at the sun. Jupiter is no longer in the JunoCam field of view on approach. When it does enter the camera field of view we see only the dark night side of Jupiter. At about 1 hour prior to closest approach the northern illuminated crescent comes into view. The north pole is clipped on one side by the edge of the field of view and by the terminator on the other. The resolution of the north pole is improving however as Juno's orbit evolves, moving the subspacecraft latitude northward on every perijove. The subspacecraft latitude at perijove on this pass is 15N. Because of the orientation of the elliptical orbit Juno has an increasingly long duration view of the south pole on departure.
We are no longer voting as it is becoming increasingly difficult to predict which storms will be in the JunoCam field of view as Juno's orbit evolves. Instead we will carry out campaigns. On PJ10 for example we devoted a number of images to looking for lightning. On this PJ11 we will use our resources to do polar timelapse sequences. In the north this is driven by a sense of urgency as the image is narrower on each pass. In the south, although our observing window is increasing in duration, we are losing resolution as the distance increases. In between the two polar time-lapse sequences images are timed to get complete latitudinal coverage.