Saturn and Titan reports
January, 2014
Bob West
Saturn Activities, June-December 2013
• Detailed Planning – Saturn segments revs 202208 (executes 2014-072 to 2014-261).
• UVIS PIEs and PRIMEs:
–
–
–
–
–
30 Auroral observations
14 EUVFUV observations
4 UVIS_20*SA_THERMOSPH***_PRIME
4 UVIS_20*SA_MOS20*APO***_PRIME
Of these, 44 in AWG group
• 15 Riders with CIRS, ISS, VIMS – long integrations
1/8/14
UVIS Team meeting Caltech - Bob West
2
Saturn – Other Issues
• Andy Ingersoll is collecting highest-priority
science items in 2015-2017 for the Senior
Review proposal
– Stellar occultations in the proximal orbits
• Input from Tommi Koskinen
– Saturn upper thermosphere/magnetosphere
• Input from Don Shemansky
1/8/14
UVIS Team meeting Caltech - Bob West
3
Triangles: already planned
or executed
Diamonds: outside 12 RS
best for UVIS
Squares: inside 12 RS
Tightly-packed squares at
the equator are
best for VIMS
From T. Koskinen, AWG meeting in
October, 2013
Update:%Temperatures%
%
Above: P-T profile used by Moses et al.
(2000).
Purple diamonds: UVIS solar occs (Koskinen et al.2013), green
squares: Voyager UVS occs (Smith et al.1983), black triangles: UVIS
stellar occultations, dashed line: GCM (Müller-Wodarg et al.2012).
3 new occultations since PSG60 (near 20S, 20N)
1/8/14
UVIS Team meeting Caltech - Bob West
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From T. Koskinen, AWG meeting in
October, 2013
Update:%Thermosphere%shape%
Left: Radius of the 0.01 nbar level
from UVIS data (diamonds), 100
mbar reference level (Anderson
and Schubert 2007). 21 UVIS
occultations included.
Right: Altitude of the 0.01 nbar level
above the 100 mbar reference, preequinox (green), post-equinox
(purple).
1/8/14
UVIS Team meeting Caltech - Bob West
6
F4: UVIS 2005 image of the Saturn thermosphere in non resonant H2 emission
This image is an extraction from the same image cube as in F1. Bifurcation in H2 population structure has never been identified in solar system
planetary atmospheres prior to the Cassini UVIS observations. H2 resonance structure has been observed in other objects such as
protoplanetary disk systems. The emission shown here is excited at lower altitudes by photoelectrons and polar auroral electrons. Intensities
are indicated on the image. Compare the strong polar emission in this image with F1. Heat deposition is weak in this component compared to
the resonance shown in F1.
From Don Shemansky
TOST Activities June 2013 – January 3, 2014
• Detailed planning T100 – T107 (executed 2014-096 to
2014-346).
• UVIS Prime Requests in this period:
– 5 EUVFUV (mix of staring and scanning), including a
chance to compare with a stellar or solar occ for airglow
model cross-calibration/science.
– Solar Occ UVIS_206SU_UTISUNOCC001_PRIME
– Stellar Occs
•
•
•
•
UVIS_204ST_ETAUMATI001_PRIME
UVIS_204ST_ETAUMATI002_PRIME
UVIS_206ST_ALPERITI001_PRIME
UVIS_208ST_ETAUMATI001_PRIME
• Numerous Rider observations, mostly with CIRS
1/8/14
UVIS Team meeting Caltech - Bob West
8
Titan (TOST) Other Issues
• T104 Radar or VIMS?
– Radar is PRIME at closest approach, but a Radar prime
pointing heats VIMS and CIRS radiators. Radar wants
to follow up on an ephemeral lake reflection observed
in only one of two previous images (wind or
something else?).
– VIMS can accomplish some high-priority specular
reflection lake (wave/wind) and other objectives
several hours after C/A if not heated. VIMS already
observed wave reflection due to wind.
– At a special meeting on Dec. 30 VIMS agreed to a
compromise plan that will heat their radiators by 6.4K
1/8/14
UVIS Team meeting Caltech - Bob West
9
Titan (TOST) Other Issues, 2
• Titan Meteorology Campaign assessment
– TMC observations lagging in 2012/2013;
requesting better cooperation from
Saturn/Rings/Icy groups
– No clouds yet in the north polar region – cloud
formation is predicted by GCMs
– New information on evolution of the ‘detached’
haze layer from ISS; the south polar vortex haze
patch is still present but receding into polar night.
1/8/14
UVIS Team meeting Caltech - Bob West
10
Titan (TOST) Other Issues, 3
• F-ring/Proximal reports on options 1, 4, and 5
[mostly RADAR; ISS/CIRS; UVIS/RSS]
– RADAR take a look at the details of the T126
groundtrack
– ISS/CIRS take a look at that series of fabulous nontargeteds in the F-Ring and Proximal timeframe
– UVIS/RSS take a look at the occultations (the ripples in
the tours go back to T115)
– RSS F-Proximal Bistat options [Aseel]
– RSS F-Proximal Titan Occultations [Aseel]
1/8/14
UVIS Team meeting Caltech - Bob West
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Titan (TOST) Other Issues, 4
1/8/14
UVIS Team meeting Caltech - Bob West
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