Date: Fri, 26 Oct 2001 11:47:56 -0700 (PDT)
From: Bob West <raw@west.jpl.nasa.gov>
To: Larry.Esposito@lasp.colorado.edu, et al.
Subject: TOST notes
Notes from the TOST meeting October 26, 2001
R. West
The first 15 minutes of the meeting were devoted to a
determination of data volume on the T5 pass. Each team needs to
make CIMS requests consistent with the allocations that were
agreed to. The T4 allocations will be done at the next meeting.
There were three main topics: Preparation for an IDS review to
take place in December or perhaps later, the TA allocation, and
the idea of replaying some of the closest approach data on the
downlink following the TOST period.
1) IDS review. The IDS review held at the PSG was poorly
attended (few IDSs) and some of the teams were not fully
prepared. Radar remains unwilling to accept the current
allocation of Radar passes, UVIS still wants the TOST to endorse
the solar occultation on T32, and there are a few other issues
that Scott and Candy want the IDSs to consider. So all the teams
have action items to provide written science rationale and to
work with their colleagues on other teams to document the
strategy for atmospheric, surface, and magnetospheric science.
For UVIS I plan to provide the science rationale that Don
Shemansky put together and to get help from the INMS, RSS, VIMS
and CIRS teams to construct a graphic showing where all the
instruments obtain coverage of the atmosphere in the current
plan. The deadline for this information gathering is November
21.
2) TA allocation: During the past two weeks there has been a
vigorous e-mail exchange debating the merits of Radar coverage
versus a UVIS solar occultation on TA. It was suggested that the
occultation might be desired by the project to assess the safety
of 950-Km flybys planned at T3 and beyond. Scott Bolton reported
on a conversation he had with Bob Mitchell who said that the
project did not need the UVIS solar occultation on TA for
operational issues and that its merit should be decided by the
TOST on a purely scientific basis. This will be a topic of a
TOST meeting on December 7.
3) Second playback for high-value Titan data: Radar requested
that their SAR images be stored on the SSR for a second playback
as insurance against data loss during station outages. Alfred
McEwen proposed that all instruments would want the same thing
for their data within +- one hour of closest approach. The TOST
group considered this proposal. On the plus side is the
realization that data during this period is very high priority
and is likely to be of higher priority than data on the downling
following the Titan downlink. On the minus side would be the
loss of opportunity to collect data during the period
immediately following the Titan downlink. The data could be
written on a safe segment of the SSR, one that is not erased on
the following downlink but by doing so that would preclude using
that portion of the SSR for data collection during the period
after the Titan flyby. The size of the replayed data could be as
large as 1.5 Gbit, although we might recommend to limit this to
something more like 500 Mbit. This issue will not be decided by
TOST but TOST is tending toward a recommendation to reserve some
(500 Mbit?) of the SSR for second playback on all orbits except
those which have unique satellite encounters or something of
equally high science value.