[X] My Assistant

[jasedm]

I feel a bit like a caretaker sweeping up in the background, what with all this Messenger Mercury activity, but here goes :
The Ciclops looking-ahead detail has been posted for Cassini's Rev 56, disappointingly, no Methone observations are slated (closest we get from here on in) but I'm sure there's a good reason.
Interestingly, they list two 'calibration sequences' for the NAC just prior to apoapse when there will be a 'stare' into the (relative) blackness of space to determine camera sensitivity, and any damage to the optics. I presume that this is so that any lens anomalies can be subtracted from subsequent images. Strikes me as good housekeeping what with the lull in Titan observations until 22nd Feb.
Ok, as you were, back to my sweeping (GO MESSENGER!!!!)

[edstrick]

If Cassini had retained a simple 1-degree of freedom (fore-and-aft) scan platform, a roll maneuver and platform slew could have permitted imaging while the antenna was on Earth for the RSS occultation. Another victim of NASA and JPL's total failure to contain costs during the "Mariner Mark II" development of a new "low cost" multi-mission outer solar system vehicle.

[rlorenz]

If Cassini had retained a simple 1-degree of freedom (fore-and-aft) scan platform, a roll maneuver and platform slew could have permitted imaging while the antenna was on Earth for the RSS occultation. Another victim of NASA and JPL's total failure to contain costs during the "Mariner Mark II" development of a new "low cost" multi-mission outer solar system vehicle.

RSS occs are pretty power-consuming. Even if there were a scan platform there might not be power
to run it and its instruments as well as all the RF downlinks near the end of the nominal mission as the RTGs
run down

I don't disagree scan platforms add enormously to flexibility during the fleeting geometric opportunities
that present themselves on a mission like Cassini, but
a) 'simple..scan platform' may define the null set
as future outer solar system Flagships are being considered and costed, people are wondering how
Cassini was as cheap as it (apparently) was

MMII would have been a bargain if implemented as originally intended - a platform designed once and
re-used for multiple missions - 2 missions for the price of 1.5, 3 missions for the price of 2 maybe.... but
as so often happens with multiple missions (remember how Pathfinder was Mesur Pathfinder....?)
budget got squeezed, CRAF got killed, and Cassini is what it is.

[ugordan]

RSS occs are pretty power-consuming.

Isn't the HGA transmitter limited to something about 20 watts? Is the TWTA the power hungry part in the equation?