This Week on Galileo - October 6-12, 1997
This week's playback schedule again contains Jupiter and Io observations, but the latter portion of the week sees the return of Callisto data to the playback schedule. The Callisto data marks the beginning of the playback schedule's second pass through the data stored on the tape recorder during Galileo's previous encounter with the Jupiter system. This second pass allows the science teams to fill in gaps caused by transmission problems in data already played back, re-play portions of observations identified as interesting enough for a second look, or return data that was previously not scheduled for return.
The first couple of days of this week's playback schedule contain observations planned for transmission last week. These observations have slipped into this week as playback was paused last week when Galileo's Deep Space Network antenna time was needed to support communications with the Mars Global Surveyor and Mars Pathfinder spacecraft. The lost transmission time has eroded the playback schedule's margin, but, as yet, has not resulted in the deletion of observations. These data include observations by the Near Infrared Mapping Spectrometer (NIMS) of Jupiter's north pole auroral and equatorial regions. Also from last week's schedule are a couple of global observations performed by the Solid State Imaging (SSI) camera of Europa and Io. The Photopolarimeter Radiometer team returns a thermal monitoring observation of Io and a regional map of Jupiter. Finally, the Ultraviolet Spectrometer team returns an observation of the south pole auroral region.
Jupiter data continues to be a primary contributor to the new data on the playback schedule. The PRR team returns two more regional observations of Jupiter while the NIMS team returns ten more observations of Jupiter's aurorae. The NIMS observations cover a variety of solar phase angles (99 deg, 114 deg, 124 deg), wavelengths (including three to five micron maps to see deep into Jupiter's atmosphere), lighting conditions (dayside, nightside), and locations (north pole, south pole). The SSI team also contributes to this set of auroral data. The team returns a single observation designed to image the area where the Io flux tube, a stream of charged particles believed to move back an forth between Io and Jupiter along Jupiter's magnetic field lines, intersects Jupiter's atmosphere and creates a visible glow.
The remainder of the playback schedule is filled with observations of Io and Callisto. The NIMS team returns observations of Io designed to monitor chemical and volcanic changes on Io. The SSI team returns an observation of Io while eclipsed from the Sun by Jupiter. This observation is designed to enable a search for hot spots and auroral emissions. Callisto data includes a global observation returned by NIMS and thermal dayside and nightside maps returned by PPR. The UVS team returns an observation of Callisto's northern latitudes while SSI returns an observation of Callisto's Asgard basin. Finally, the fields and particles instruments return high time-resolution data captured during the spacecraft's closest 60 minutes of the Callisto flyby.